Abstract
In this work, we study vibrations of three-layered cylindrical shells with one ring support along its length. Nature of material of the central layer is a functionally graded material (FGM) type. The considered FGM is of stainless steel and nickel. The internal and external layers are presumed to be made of isotropic material i.e., aluminum. The functionally graded material composition of the center layer is assorted by three volume fraction laws (VFL) which are represented by mathematical expressions of polynomial, exponential and trigonometric functions. The implementation of Rayleigh-Ritz method has been done under the Sanders’ shell theory to obtain the shell frequency equation. Natural frequencies (NFs) are attained for the present model problem under six boundary conditions. Use of characteristic beam functions is made for the estimation of the dependence of axial modals. The impact of layer material variations with ring support is considered for many ring positions. Also the effect of volume fraction laws is investigated upon vibration characteristics. This investigation is performed for various physical parameters. Numerous comparisons of values of shell frequencies have been done with available models of such types of results to verify accuracy of the present formulation and demonstrate its numerical efficiency.
1 Introduction
A cylindrical shell is a significant element in structural dynamics. Different mechanical aspects of such types of shells are studied for their practical applications, shell vibration is one of them. This investigation of these shells play a paramount part in the fields of technology, like pressure vessels, nuclear power plants, piping system and other marine and aircraft applications. Many researches [1, 2, 3, 4, 5, 6, 7, 8] have been done the studies on vibrational performance of functionally graded (FG) cylindrical shells (CSs) and influence on the frequencies of layered shells due to edge conditions has been studied by Loy and Lam [9]. The core of all the previous research work has been elaborated by Love’s thin shell theory. Furthermore Loy and Lam [10] gave an investigation of frequency characteristics of thin walled cylindrical shell (CS) under ring supports for several end conditions by using Sanders’ shell theory and Ritz formulation. Xiang et al. [11] used Goldenveizer-Novozhilov theory of shells to determine the exact vibration solution of the same circular cylinders supported by multiple transitional rings. The state-space technique was applied to obtaine shell governing equations for shell splinter and the influences of edge conditions were attained. The effects on frequency parameters for different locations of ring supports were observed. The vibration behavior of open circular cylinders grounded on intermediary ring elastic support was analyzed by Zhang and Xiang [12]. They assessed the influence for number of intermediate ring assistances, their positions, associated boundary conditions and variations included angles on the behavior of the shells. Swaddiwudhipong et al. [13] explained the study of vibration of CSs with middle supports by applying the Ritz method to approximate their frequencies and mode shapes. An analysis of vibration frequency for a FG shell was done by Arshad et al. [14] with effect of different fraction laws by applying Love’s first order shell theory. Another study about the frequency analysis of bi-layered CSs has been presented by the same authors in [15]. The shells were assembled from functionally graded materials (FGMs) as well as isotropic materials. The influences of particular shell configurations on NFs of cylinder-shaped shells were scrutinized. The solidity of the same shells made up of FG structure layer associated with axial load placed on the Winkler-Pasternak foundations was analyzed by Sofiyev and Avear [16]. Arshad et al. [17] explored vibration properties of bi-layered cylinder-shaped shell with both layers made up of FG layers by considering constant thickness. Law-II was exploited to study the material distribution of FGMs. They studied the effect on vibrations of double layered FG shell for various shell constraints, edge conditions and exchange the essential materials making FGMs. Zhang et al. [18] investigated the shell free vibrations for a number of edge conditions by using a differential quadrature type procedure. Naeem et al. [19] analyzed vibration behavior of the tri-layered FGM circular cylinders. They employed the Ritz method and used the Love’s shell theory. Governing mathematical expression was in an integral form by considering the shell strain and kinetic energy relations. Axial modal dependence was examined with solution functions of beam equation. Arshad et al. [20] made a study of FG three-layered cylinder-shaped shells for free vibration under a ring support. Their work deals with the effect of ring supports, located at different positions along the length of cylinder-shaped shell for different edge conditions. The analysis was based on Love’s thin shell theory. Rayleigh-Ritz formulation was employed to obtain solutions of the problem. The vibration response of tri-layered shells was investigated by Li et al. [21]. Ghamkhar et al. [22] studied vibration frequency analysis for three layered cylinder shaped shell with FGM central layer. The effect on shell vibrations for different thickness of the central layer were examined by them. The analysis was based on sander’s shell theory and Ritz mathematical approach. Functionally graded material distribution was controlled with trigonometric volume fraction law.
In this work, vibration frequencies are analyzed for three layered cylindrical shells. These shells are assembled from three layers assuming that the central is made of functionally graded materials, internal and external layers remain isotropic type of materials. Material of the central layer is controlled by following volume fraction laws, polynomial (Law-I), exponential (Law-II) and trigonometric (Law-III). These laws are framed by polynomial, exponential and trigonometric functions. These laws vary the material composition in the radial (through-thickness) direction.
This material variation yields a variety of frequency spectra. Stability of these shells is solidified by ring supports around the tangential directions. Sanders’ thin shell theory is adopted for shell governing equations. These equations are solved by applying Rayleigh Ritz technique involving an energy variation functional. Axial deformation functions are estimated by the solution functions of beam equation. Such functions are taken to meet the edge conditions. An effect of layer thickness configurations is observed on shell natural frequencies. Results are obtained to examine the influence of ring supports at different positions along the shell length.
2 Theoretical considerations
Consider a cylinder-shaped shell sketched in Figure 1. Here length of the shell is denoted byL, thickness is denoted by H and the mean radius symbolized byR. They represent the shell geometrical quantities. A cylindrical coordinate system (x, δ, z) is framed at the shell middle reference surface with x, δ and z as the axial, angular and thickness coordinates respectively. Deformation displacement functions are designated byu1(x, δ, t), u2(x, δ, t) and u3(x, δ, t) which denote the displacement deformations in the longitudinal, tangential and transverse directions respectively. The strain energy ℑ for a thin vibrating CS as in [10] is described below:

Geometry of CS with a ring support that its location varies along the length
where
and ∈1 , ∈2 and ∈12 denote strains which are related to the reference surface and k1, k2 and k12 represent curvatures. Prime (′) indicates the matrix transposition. The entries of the matrix [C] are furnished as:
where xij represent the extensional, yij, coupling and zij , bending stiffness. (i, j = 1, 2 and 6). They are defined by the following formulas:
The reduced stiffness Qij for isotropic materials is stated as [10]:
Here E represents the Young’s modulus and μ denotes the Poisson ratio. The matrix yij = 0 for isotropic circular shaped CS and yij ≠ 0 for a FG cylindrical shell; its value determined by the arrangement and properties of its constituent materials. After substituting the expressions from (2) and (3) in (1), ℑ is rewritten as:
Following expressions are taken from [23] and written as
By substituting expressions (7) and (8) into equation (6), then ℑ becomes as:
The kinetic energy T for a CS is expressed as:
here time variable is denoted by t and the mass density per unit length is represented by ρt and is written as:
where ρ is mass density.
The Lagrange energy functional Г for a CS is defined as a function of the kinetic and strain energies as:
3 Numerical Procedure
The present cylindrical shell is solved by the Rayleigh-Ritz technique. Its deformation displacement fields are expressed in terms of product of functions of space and time variables. These functions for a CS with ring supports can
be assumed in the longitudinal, tangential and transverse directions as:
here
where the values of βi , (i = 1, 2, 3, 4),depend upon the nature of the edge conditions and αm denotes the roots of trigonometric or hyperbolic equations and the parameters, χm ′s depend on values of αm.
Following dimensionless parameters are utilized to simplify the problem.
Now the expressions (13) are re-written as:
After making substitutions of the expressions (16) and their respective derivatives into the relations (9) and (10), ℑmax and Tmax are obtained using the principle of conservation of energy. By applying the principle of maximum energy, the Lagrange functional, Гmax takes the following form:
4 Formation of eigenvalue frequency equation
The shell eigenvalue frequency equation is derived by making a use of the Rayleigh-Ritz technique. The energy Lagrange functional Гmax is extremized with regard to vibration coefficients: am, bm and cm, we obtain the following relations.
A system of homogeneous simultaneous equations in am, bm and cm is generated and is transformed into the eigenvalue problem as.
where [K] is the stiffness matrix and [M]represents the mass matrix and
and
The elements of [K] and [M] are given in the Appendix 1. MATLAB software is used to solve the eigenvalue problem (19) for the shell frequency spectra for various physical parameters.
5 Functionally graded materials
In practice of three layered cylindrical shell, its central layer is fabricated by FGMs and isotropic is used for internal and external layers as shown in Figure 2. Here the stiffness moduli are altered as:

Cross-section of three-layered CS.
where i,j=1, 2, 6 and superscript int(I), ext(I) represent the isotropic internal and external layers and cen(F) denotes the central FGM layer. The functionally graded materials contain two essential materials. These materials are stainless steel and nickel. The material parameters for stainless steel material are: E2, μ2,ρ2 and for nickel material are: E1, μ1,ρ1. The thickness of each layer is presumed to be H/3. Then the actual material quantities for FGM layer are
given as:
The material properties for middle FGM layer vary from z = −H/6 to H/6. From the relations (23a-c), the effective material properties become EF = E2, μF = μ2 and ρF = ρ2 at z = −H/6 where for z = H/6 material properties becomeEF = E1, μF = μ1 and ρF = ρ1. Thus forz = −H/6 , the shell is contained only stainless steel whereas for z = H/6 consisted of nickel material. In a FGM shell, the distribution of materials is controlled by various volume fraction laws. Three volume fraction laws are expressed in mathematical form. If z symbolizes the basic shell thickness variable then the volume fraction law VF of a FGM is formulated as following function [24]
where H represents the thickness of cylinder-shaped shell and N denotes the power law proponent which may take values from zero to infinity. A volume fraction law formulated by Arshad et al. [14] as:
where e be the standard irrational natural exponential base number. The material properties are written as:
Trigonometric volume fraction law for a FGM circular CS is stated as:
Here
The material parameters for FG cylindrical shell are written as:
6 Results and discussion
To check the validity of the current work, results for simply supported and clamped CSs with no ring support are compared with others available in the literature. A good agreement is found among the present results and those obtained by other techniques. In Table 1, a comparison of frequency parameters
Comparison of frequency parameter
L/R | n | n | n | n | |
---|---|---|---|---|---|
1 | 2 | 3 | 4 | ||
20 | Zhang et al.[18] | 0.016102 | 0.039271 | 0.109811 | 0.210277 |
20 | Present | 0.0161029 | 0.0392713 | 0.1098115 | 0.2102771 |
20 | Difference % | 0.006 | 0.001 | 0.001 | 0.000 |
Comparison of frequency parameter
L/R | n | n | n | n | |
---|---|---|---|---|---|
1 | 2 | 3 | 4 | ||
20 | Zhang et al.[18] | 0.03285 | 0.040638 | 0.109973 | 0.210324 |
20 | Present | 0.03440 | 0.040772 | 0.110005 | 0.210376 |
20 | Difference % | 4.7 | 0.33 | 0.03 | 0.02 |
Comparison of natural frequencies (Hz) for type I FGM cylindrical shell with simply supported edges. (m = 1, H/R = 0.002, L/R = 20)
Loy et al. [1] | Present | |||||
---|---|---|---|---|---|---|
N | N | |||||
n | 0.5 | 1 | 2 | 0.5 | 1 | 2 |
1 | 13.321 | 13.211 | 13.103 | 13.321 | 13.210 | 13.103 |
2 | 4.5168 | 4.4800 | 4.4435 | 4.5098 | 4.4746 | 4.4396 |
3 | 4.1911 | 4.1569 | 4.1235 | 4.1520 | 4.1356 | 4.1154 |
4 | 7.0972 | 7.0384 | 6.9820 | 7.0189 | 7.0000 | 6.9721 |
5 | 11.336 | 11.241 | 11.151 | 11.210 | 11.181 | 11.138 |
Types of shell w. r. t the arrangements of shell layers
Types | Internal Layer | Central FGM Layer | External Layer |
---|---|---|---|
Type I | MA | MB/MC | MA |
Type II | MA | MC/MB | MA |
Thickness variation of the FGM shell layers
Thickness Patterns | Inner isotropic Layer | Central FGM Layer | External isotropic Layer |
---|---|---|---|
Case 1 | H/3 | H/3 | H/3 |
Case 2 | H/4 | H/2 | H/4 |
Case 3 | H/5 | 3H/5 | H/5 |
Table 6-8 show the variation of NFs (Hz) versus n for three layered FGMs type I CS with ring supports. Thickness of the center layer is presumed to be H/3, H/2 and 3H/5 for Tables 6-8 respectively. In these Tables, the influence of three VFL is perceived for six edge conditions: simply supported-simply supported (SS − SS), clamped-clamped (C−C), free-free (F−F), clamped-simply supported (C−SS), clamped-free (C − F) and free-simply supported (F − SS).It is noticed that the NF increased with the increase of n. It is also examined that the C − C edge condition has the maximum NFs (Hz) and C − F has the really minimum. It is studied that natural frequencies increasing swiftly from n is equal to 1 to 2 then its increasing steadily. In Table 6, Law-I gets the extreme frequencies (Hz) and Law-III takes the lowest frequencies (Hz). Table 7 & 8 represent the variation of NFs (Hz) of FGM shell by using Law-I for six boundary conditions.
Variation of NFs (Hz) for Type I & Case 1 FGM CS against n with ring support. (L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1)
n | SS − SS | C − C | F − F | C − SS | C − F | F − SS | |
---|---|---|---|---|---|---|---|
Law I | 1 | 505.393 | 513.611 | 503.363 | 507.878 | 278.876 | 503.485 |
2 | 848.181 | 848.183 | 48.182 | 762.667 | 349.123 | 817.553 | |
3 | 848.297 | 848.3 | 48.299 | 773.636 | 367.637 | 822.354 | |
4 | 848.604 | 848.61 | 848.608 | 777.258 | 375.168 | 823.97 | |
5 | 849.247 | 849.256 | 849.253 | 779.396 | 379.799 | 825.189 | |
6 | 850.411 | 850.424 | 850.42 | 781.42 | 384.072 | 826.677 | |
7 | 852.321 | 852.338 | 852.333 | 783.941 | 389.226 | 828.811 | |
8 | 855.239 | 855.261 | 855.254 | 787.392 | 396.115 | 831.918 | |
9 | 859.46 | 859.488 | 859.479 | 792.16 | 405.447 | 836.328 | |
10 | 865.311 | 865.346 | 865.335 | 798.631 | 417.851 | 842.389 | |
Law II | 1 | 504.242 | 512.441 | 502.216 | 506.72 | 278.238 | 502.338 |
2 | 846.248 | 846.25 | 846.249 | 760.929 | 348.327 | 815.69 | |
3 | 846.377 | 846.38 | 846.379 | 771.884 | 366.804 | 820.492 | |
4 | 846.701 | 846.706 | 846.705 | 775.514 | 374.326 | 822.122 | |
5 | 847.366 | 847.374 | 847.372 | 777.669 | 378.96 | 823.36 | |
6 | 848.556 | 848.569 | 848.565 | 779.715 | 383.24 | 824.874 | |
7 | 850.497 | 850.514 | 850.509 | 782.264 | 388.404 | 827.038 | |
8 | 853.45 | 853.472 | 853.465 | 785.747 | 395.305 | 830.179 | |
9 | 857.711 | 857.739 | 857.73 | 790.55 | 404.65 | 834.627 | |
10 | 863.605 | 863.64 | 863.629 | 797.06 | 417.066 | 840.73 | |
Law III | 1 | 503.416 | 511.602 | 501.394 | 505.891 | 277.779 | 501.515 |
2 | 844.84 | 844.841 | 844.841 | 759.663 | 347.748 | 814.332 | |
3 | 844.949 | 844.952 | 844.951 | 770.583 | 366.186 | 819.108 | |
4 | 845.246 | 845.252 | 845.25 | 774.182 | 373.684 | 820.709 | |
5 | 845.875 | 845.884 | 845.881 | 776.302 | 378.294 | 821.913 | |
6 | 847.022 | 847.035 | 847.031 | 778.307 | 382.549 | 823.383 | |
7 | 848.911 | 848.928 | 848.922 | 780.806 | 387.683 | 825.495 | |
8 | 851.802 | 851.825 | 851.817 | 784.231 | 394.548 | 828.577 | |
9 | 855.993 | 856.021 | 856.012 | 788.969 | 403.85 | 832.956 | |
10 | 861.808 | 861.843 | 861.831 | 795.404 | 416.218 | 838.981 |
Variation of NFs (Hz) for Type I & Case 2 FGM CS against n with ring support. (L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1)
n | SS − SS | C − C | F − F | C − SS | C − F | F − SS |
---|---|---|---|---|---|---|
1 | 499.678 | 507.874 | 497.709 | 502.171 | 276.964 | 497.805 |
2 | 842.358 | 842.36 | 842.359 | 757.432 | 346.726 | 811.926 |
3 | 842.477 | 842.481 | 842.48 | 768.329 | 365.114 | 816.711 |
4 | 842.788 | 842.793 | 842.792 | 771.93 | 372.594 | 818.322 |
5 | 843.433 | 843.441 | 843.438 | 774.059 | 377.193 | 819.538 |
6 | 844.595 | 844.608 | 844.603 | 776.074 | 381.434 | 821.022 |
7 | 846.498 | 846.515 | 846.509 | 778.583 | 386.546 | 823.147 |
8 | 849.4 | 849.422 | 849.415 | 782.012 | 393.376 | 826.237 |
9 | 853.595 | 853.623 | 853.613 | 786.748 | 402.625 | 830.619 |
10 | 859.406 | 859.44 | 859.428 | 793.172 | 414.918 | 836.637 |
Variation of NFs (Hz) for Type I & Case 3 FGM CS against n with ring support. (L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1)
n | SS − SS | C − C | F − F | C − SS | C − F | F − SS |
---|---|---|---|---|---|---|
1 | 496.300 | 504.482 | 494.366 | 498.797 | 275.838 | 494.447 |
2 | 838.929 | 838.931 | 838.930 | 754.349 | 345.315 | 808.612 |
3 | 839.052 | 839.055 | 839.054 | 765.205 | 363.630 | 813.389 |
4 | 839.367 | 839.372 | 839.371 | 768.797 | 371.083 | 815.000 |
5 | 840.017 | 840.026 | 840.023 | 770.925 | 375.671 | 816.220 |
6 | 841.186 | 841.199 | 841.195 | 772.943 | 379.906 | 817.709 |
7 | 843.096 | 843.113 | 843.108 | 775.456 | 385.014 | 819.840 |
8 | 846.006 | 846.028 | 846.021 | 778.891 | 391.839 | 822.937 |
9 | 850.209 | 850.236 | 850.227 | 783.633 | 401.082 | 827.326 |
10 | 856.027 | 856.061 | 856.050 | 790.062 | 413.365 | 833.350 |
Table 9-11 describe the variation of NFs (Hz), effects of shell configurations on NFs (Hz) versus n for FGM shell type II with ring supports. Thickness of the center layer is supposed as same as for Table 6, 7 and 8 respectively. Law-I gets the lowest values and Law-III takes extreme values of NFs (Hz) in Table 9. Table 12 represents the natural frequency (Hz) of three layered CS of case1 versus n with and without ring support for SS−SS boundary conditions. The behavior of frequency remains same according to the circumferential wave number n and volume fraction laws for both CSs with and without ring support. Table 12 shows that the NFs of CS with ring support are higher than frequencies of the CS without ring support.
Variation of NFs (Hz) for Type II & Case 1 FGM CS against n with ring support. (L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1)
n | SS − SS | C − C | F − F | C − SS | C − F | F − SS | |
---|---|---|---|---|---|---|---|
Law I | 1 | 505.880 | 514.077 | 503.833 | 508.352 | 278.623 | 503.965 |
2 | 847.410 | 847.411 | 847.411 | 761.974 | 348.805 | 816.815 | |
3 | 847.519 | 847.522 | 847.521 | 772.927 | 367.301 | 821.601 | |
4 | 847.817 | 847.823 | 847.821 | 776.537 | 374.822 | 823.206 | |
5 | 848.448 | 848.457 | 848.455 | 778.664 | 379.448 | 824.413 | |
6 | 849.598 | 849.612 | 849.608 | 780.676 | 383.719 | 825.889 | |
7 | 851.492 | 851.513 | 851.508 | 783.185 | 388.875 | 828.010 | |
8 | 854.393 | 854.422 | 854.415 | 786.624 | 395.770 | 831.104 | |
9 | 858.598 | 858.636 | 858.628 | 791.383 | 405.114 | 835.503 | |
10 | 864.433 | 864.483 | 864.473 | 797.847 | 417.537 | 841.553 | |
Law II | 1 | 507.040 | 515.256 | 504.988 | 509.517 | 279.264 | 505.120 |
2 | 849.352 | 849.353 | 849.353 | 763.720 | 349.605 | 818.687 | |
3 | 849.448 | 849.452 | 849.451 | 774.687 | 368.137 | 823.471 | |
4 | 849.729 | 849.735 | 849.733 | 778.289 | 375.667 | 825.063 | |
5 | 850.339 | 850.348 | 850.345 | 780.399 | 380.291 | 826.250 | |
6 | 851.463 | 851.477 | 851.472 | 782.388 | 384.555 | 827.701 | |
7 | 853.329 | 853.346 | 853.341 | 784.870 | 389.701 | 829.792 | |
8 | 856.197 | 856.220 | 856.213 | 788.277 | 396.584 | 832.852 | |
9 | 860.367 | 860.395 | 860.386 | 793.000 | 405.916 | 837.212 | |
10 | 866.165 | 866.199 | 866.188 | 799.426 | 418.327 | 843.222 | |
Law III | 1 | 507.880 | 516.109 | 505.824 | 510.361 | 279.730 | 505.956 |
2 | 850.780 | 850.782 | 850.781 | 765.004 | 350.192 | 820.064 | |
3 | 850.896 | 850.899 | 850.898 | 776.006 | 368.763 | 824.874 | |
4 | 851.204 | 851.210 | 851.208 | 779.639 | 376.318 | 826.495 | |
5 | 851.849 | 851.858 | 851.855 | 781.785 | 380.965 | 827.717 | |
6 | 853.018 | 853.030 | 853.026 | 783.815 | 385.255 | 829.211 | |
7 | 854.935 | 854.953 | 854.947 | 786.347 | 390.431 | 831.354 | |
8 | 857.865 | 857.887 | 857.880 | 789.812 | 397.350 | 834.474 | |
9 | 862.105 | 862.133 | 862.124 | 794.601 | 406.725 | 838.903 | |
10 | 867.982 | 868.017 | 868.006 | 801.101 | 419.185 | 844.991 |
Variation of NFs (Hz) for Type II & Case 2 FGM CS against n with ring support. (L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1).
n | SS − SS | C − C | F − F | C − SS | C − F | F − SS |
---|---|---|---|---|---|---|
1 | 500.409 | 508.573 | 498.414 | 502.883 | 276.586 | 498.525 |
2 | 841.206 | 841.208 | 841.207 | 756.396 | 346.253 | 810.824 |
3 | 841.310 | 841.313 | 841.312 | 767.265 | 364.611 | 815.580 |
4 | 841.600 | 841.606 | 841.604 | 770.843 | 372.076 | 817.169 |
5 | 842.221 | 842.230 | 842.227 | 772.949 | 376.667 | 818.362 |
6 | 843.356 | 843.369 | 843.365 | 774.940 | 380.907 | 819.820 |
7 | 845.231 | 845.248 | 845.243 | 777.424 | 386.029 | 821.918 |
8 | 848.107 | 848.129 | 848.122 | 780.833 | 392.880 | 824.983 |
9 | 852.279 | 852.307 | 852.298 | 785.553 | 402.168 | 829.344 |
10 | 858.073 | 858.108 | 858.096 | 791.967 | 414.518 | 835.348 |
Variation of NFs (Hz) for Type II & Case 3 FGM CS against n with ring support.(L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1).
n | SS − SS | C − C | F − F | C − SS | C − F | F − SS |
---|---|---|---|---|---|---|
1 | 497.177 | 505.321 | 495.213 | 499.652 | 275.387 | 495.311 |
2 | 837.550 | 837.551 | 837.551 | 753.109 | 344.748 | 807.294 |
3 | 837.650 | 837.653 | 837.652 | 763.926 | 363.024 | 812.031 |
4 | 837.933 | 837.938 | 837.936 | 767.484 | 370.452 | 813.608 |
5 | 838.542 | 838.551 | 838.548 | 769.572 | 375.016 | 814.787 |
6 | 839.661 | 839.674 | 839.670 | 771.543 | 379.227 | 816.227 |
7 | 841.513 | 841.530 | 841.524 | 774.002 | 384.310 | 818.302 |
8 | 844.356 | 844.378 | 844.371 | 777.376 | 391.108 | 821.334 |
9 | 848.485 | 848.513 | 848.504 | 782.050 | 400.323 | 825.651 |
10 | 854.223 | 854.257 | 854.246 | 788.406 | 412.578 | 831.597 |
Variation of NFs (Hz) of three layered FGM CS Type I & Case1 versus circumferential wave number (n). (L/R = 50, m = 1, H/R = 0.007, a = 0.5, N = 1).
without ring support | with ring support | |
---|---|---|
n | Type I | Type I |
1 | 1.6289 | 505.393 |
2 | 4.6222 | 848.181 |
3 | 12.991 | 848.297 |
4 | 24.903 | 848.604 |
5 | 40.271 | 849.247 |
6 | 59.076 | 850.411 |
7 | 81.309 | 852.321 |
8 | 106.968 | 855.239 |
9 | 136.052 | 859.460 |
10 | 168.559 | 865.311 |
Table 13 demonstrates NFs (Hz) with ratios (L/R) for type I & case 1 FGM shell. The natural frequencies decreased less than 0.5%with the increasing values of N.Natural frequencies decreased 11% and 14% when L/R becomes 10 and 20 respectively.
Natural Frequencies (Hz) of Type I & Case 1 FGM CS with ring support versus length to radius ratios L/R. (n = 1, m = 1, , H/R = 0.005, a = 0.5).
L/R | N=1 | N=2 | N=3 | N=4 | N=5 | N=10 | N=20 | N=30 | N=50 |
---|---|---|---|---|---|---|---|---|---|
5 | 595.701 | 593.988 | 593.135 | 592.625 | 592.285 | 591.513 | 591.067 | 590.905 | 590.763 |
10 | 528.705 | 527.184 | 526.427 | 525.973 | 525.672 | 524.985 | 524.587 | 524.440 | 524.309 |
20 | 510.584 | 509.115 | 508.384 | 507.946 | 507.655 | 506.991 | 506.607 | 506.464 | 506.337 |
The thickness of each layer of the shell for Figure 3-8 is H/3. Natural frequency varies with respect to the ring support position and this influence changes according to edge conditions. Figure 3 shows the variation of NF of SS − SS shell with the position of ‘a’ for different L/R ratios. Natural frequencies are obtained for law-I, law-II and law-III. The movements of these VFL, for frequency curve at a = 0, the values are 328.96 , 328.51, 327.88, at a = 0.5, the values are 593.99, 593.17, 592.85 and at a = 1,values are 328.97, 328.51, 327.89 for law-I, law-II and law-III respectively. The behavior of the frequency curve is increasing from a = 0 to a = 0.5 and decreasing from a = 0.5 to a = 1. So it is a symmetric curve. Similar behavior studied for L/R =10, 20 and also for C − C and F − F edge conditions. Moreover, law-II is consisted between the law-I & III. Frequency curves are overlapping because the values for all laws are so closed to each other. So for other boundary conditions law-III is selected to draw because it attains minimum frequency values. Figure 4 shows the same results for clamped-clamped edge condition. Frequencies are significantly high for clamped-clamped end condition. In Figure 5 variation of NFs (Hz) of three-layered FGM cylindrical shell is plotted against the ring supports position. So the frequency value at a = 0, is 260.46 and the extreme NF (Hz) for law-III lies at a = 0.6, frequency is 683.25. The last value of frequency curve is 278.24 lies at a = 1,. Similar behavior displays for L/R = 10 and 20. In Figure 6. The frequency curve is increasing gradually from a = 0 to 0.5 then gets its extreme value at a = 0.8, after this curve starts to decrease. Here the frequency curve is not chime formed because of different edge condition. It is noticed that the behavior of NFs curves for all ratios and laws are same. Figures 7 and 8 exhibits variation of NFs (Hz) versus n for different N with a = 0.5 for SS−SS and C−C end point conditions. Here N differs as 0.5, 1 and 2. Here frequency curves increase rapidly from n = 1 to 2 and then these curves start to increase linearly through n. It is noticed that with the increase in power law exponent N natural frequency is not really affected.

Variation of NFs (Hz) of three-layered FGM CS versus ring supports position ‘a’ at different L/R ratios for SS − SS edge conditions. (m = 1, n = 1, H/R = 0.005 and N = 2)

Variation of NFs (Hz) of three-layered FGM CS with ring supports position ‘a’ at different L /R ratios for Law-I, C − C edge conditions. (m = 1, n = 1, H/R = 0.005 and N = 2)

Variation of NFs (Hz) of three-layered FGM CS versus ring supports position ‘a’ at different L /R ratios for C−SS edge conditions. (m = 1, n = 1, H/R = 0.005 and N = 2)

Variation of NFs (Hz) of three-layered FGM CS versus ring supports position ‘a’ at different L /R ratios for C − F edge conditions. (m = 1, n = 1, H/R = 0.005 and N = 2)

Variation of NFs (Hz) of FGM cylindrical shell versus (n) for different N with SS − SS edge conditions. (m=1, L/R=50, H/R=0.007)

Variation of NFs (Hz) of FGM cylindrical shell versus (n) for different N with C − C edge conditions. (m=1, L/R=50, H/R=0.007)
7 Conclusions
The frequency analysis of three-layered FGM cylindrical shell is performed to determine the effect of ring support. The shell central layer is made of FGMs while the internal and external layers are of isotropic material. Variation of NFs (Hz) is analyzed for six boundary conditions. It is concluded that the material dissemination controlled by the VFL which has little effect (<1%) on vibration frequency of a FGM CS but law-III is recommended for type 1 FGM shell and law-I is for type 2 FGM shell to estimate the lower frequency values.
Natural frequencies are increased with the increase of n and decreased with the increase of L/R ratios. Natural frequency also decreased <2% when increase in the thickness of the central layer becomes double. The frequency curve of the shell with ring support at different positions get symmetric shapes because of same edge conditions. They are not symmetrical about center because of different end point conditions. The induction of ring support on cylinder-shaped shell has significant effect on the NFs as compared to the shell frequencies without ring support.
References
[1] Loy C. T., Lam K.Y., and Reddy J.N., Vibration of functionally graded cylindrical shells, Int. J. Mech. Sci., 1999, 41, 309-324.10.1016/S0020-7403(98)00054-XSearch in Google Scholar
[2] Pradhan S.C., Loy, C.T., Lam K.Y., and Reddy J.N., Vibration characteristics of functionally graded cylindrical shells under various boundary conditions. Appl. Acoust., 2000, 61, 111-129.10.1016/S0003-682X(99)00063-8Search in Google Scholar
[3] Chen W.Q., Bian Z.G., and Ding H.J., Three-dimensional vibration analysis of fluid-filled orthotropic FGM cylindrical shells, Int. J. Mech. Sci., 2004, 46, 159-171.10.1016/j.ijmecsci.2003.12.005Search in Google Scholar
[4] Zhi-Yuan C., and Hua-Ning W., Free vibration of FGM cylindrical shells with holes under various boundary conditions, J. Sound Vib. 2007, 306, 227-237.10.1016/j.jsv.2007.05.019Search in Google Scholar
[5] Haddadpour H., Mahmoudkhani S., and Navazi H.M., Free vibration analysis of functionally graded cylindrical shells including thermal effects, Thin-Walled Structures, 2007, 45, 591-599.10.1016/j.tws.2007.04.007Search in Google Scholar
[6] Iqbal Z., Naeem, M.N., and Sultana, N., Vibration characteristics of FGM circular cylindrical shells using wave propagation approach, Acta Mech., 2009, 208, 237-248.10.1007/s00707-009-0141-zSearch in Google Scholar
[7] Iqbal Z., Naeem, M.N., Sultana, N., Arshad, S.H., and Shah, A.G., Vibration characteristics of FGM circular cylindrical shells filled with fluid using wave propagation approach, Appl. Math. Mech.,2009, 30, 1393-1404.10.1007/s10483-009-1105-xSearch in Google Scholar
[8] Niino M., Hirai T., and Watanabe R., The functionally gradient materials, J. Jap. Soc. Comp. Mater, 1987, 13, 257-264.10.6089/jscm.13.257Search in Google Scholar
[9] Lam, K.Y., and Loy, C.T., Effects of boundary conditions on frequencies of a multi-layered cylindrical shell, J. Sound Vib., 1995, 188, 363-384.10.1006/jsvi.1995.0599Search in Google Scholar
[10] Loy, C.T., and Lam, K.Y., Vibration of cylindrical shells with ring support, Int. J. Mech. Sci., 1997, 39, 455-471.10.1016/S0020-7403(96)00035-5Search in Google Scholar
[11] Xiang, Y.,Ma, Y.F., Kitipornchai, S., Lim, C.W., and Lau, C.W.H., Exact solutions for vibration of cylindrical shells with intermediate ring supports, Int. J. Mech. Sci., 2002, 44, 1907-1924.10.1016/S0020-7403(02)00071-1Search in Google Scholar
[12] Zhang L., and Xiang Y., Vibration of open circular cylindrical shells with intermediate ring supports, Int. J. Solids Struct., 2006, 43, 3705-3722.10.1016/j.ijsolstr.2005.05.058Search in Google Scholar
[13] Swaddiwudhipong, S., Tian, J., and Wang, C. M., Vibrations of cylindrical shells with intermediate supports, J. Sound Vib., 1995, 187, 69-93.10.1006/jsvi.1995.0503Search in Google Scholar
[14] Arshad S.H., Naeem M.N., and Sultana N., Frequency analysis of functionally graded cylindrical shells with various volume fraction laws, J. Mech. Eng. Sci., 2007, 221, 1483-1495.10.1243/09544062JMES738Search in Google Scholar
[15] Arshad S.H., Naeem M.N., Sultana N., Shah,A.G., and Iqbal Z., Vibration analysis of bi-layered FGM cylindrical shells, Arch. Appl. Mech., 2011, 81, 319-343.10.1007/s00419-010-0409-8Search in Google Scholar
[16] Sofiyev A.H., and Avcar, M., The stability of cylindrical shells containing an FGM layer subjected to axial load on the Pasternak foundation, Engineering, 2010, 2, 228-236.10.4236/eng.2010.24033Search in Google Scholar
[17] Arshad S.H., Naeem M.N., Sultana N., Iqbal Z., and Shah A.G., Vibration of bi-layered cylindrical shells with layers of different materials, J. Mech. Sci. Tech, 2010, 24, 805-810.10.1007/s12206-010-0122-0Search in Google Scholar
[18] Zhang L., Xiang Y., and Wei G.W., Local adaptive differential quadrature for free vibration analysis of cylindrical shells with various boundary conditions, Int. J. Mech. Sci., 2006, 48, 1126-1138.10.1016/j.ijmecsci.2006.05.005Search in Google Scholar
[19] Naeem M.N., Khan A.G., Arshad S.H., Shah A.G., and Gamkhar M., Vibration of three-layered FGM cylindrical shells with middle layer of isotropicmaterial for various boundary conditions, World J. Mech., 2014, 4, 315-331.10.4236/wjm.2014.411032Search in Google Scholar
[20] Arshad S.H., Naeem M.N., and Soutis, C., Influence of ring support on free vibration of sandwich functionally graded cylindrical shells with middle layer of isotropic material, J. Eng. Res., 2016, 4, 159-186.10.7603/s40632-016-0009-zSearch in Google Scholar
[21] Li S.R., Fu X.H., and Batra R.C., Free vibration of three-layer circular cylindrical shells with functionally graded middle layer, Mech. Res. Commun., 2010, 37, 577-580.10.1016/j.mechrescom.2010.07.006Search in Google Scholar
[22] Ghamkhar M., Naeem, M.N., Imran M., Kamran M., and Soutis, C., Vibration frequency analysis of three-layered cylinder shaped shell with effect of FGM central layer thickness, Scientific Reports, 2019, 9, 1566. 10.1038/s41598-018-38122-0Search in Google Scholar PubMed PubMed Central
[23] Sanders Jr J.L., An improved first-approximation theory for thin shells, NASA Rep. (1959)Search in Google Scholar
[24] Chi S.H. and Chung Y.L., Mechanical behavior of functionally graded material plates under transverse load part II: numerical results, Int. J. Solids Struct., 2006, 43, 3657–3691.10.1016/j.ijsolstr.2005.04.010Search in Google Scholar
Appendix
where
© 2019 M. Ghamkhar et al., published by De Gruyter
This work is licensed under the Creative Commons Attribution 4.0 International License.
Articles in the same Issue
- Regular Articles
- Non-equilibrium Phase Transitions in 2D Small-World Networks: Competing Dynamics
- Harmonic waves solution in dual-phase-lag magneto-thermoelasticity
- Multiplicative topological indices of honeycomb derived networks
- Zagreb Polynomials and redefined Zagreb indices of nanostar dendrimers
- Solar concentrators manufacture and automation
- Idea of multi cohesive areas - foundation, current status and perspective
- Derivation method of numerous dynamics in the Special Theory of Relativity
- An application of Nwogu’s Boussinesq model to analyze the head-on collision process between hydroelastic solitary waves
- Competing Risks Model with Partially Step-Stress Accelerate Life Tests in Analyses Lifetime Chen Data under Type-II Censoring Scheme
- Group velocity mismatch at ultrashort electromagnetic pulse propagation in nonlinear metamaterials
- Investigating the impact of dissolved natural gas on the flow characteristics of multicomponent fluid in pipelines
- Analysis of impact load on tubing and shock absorption during perforating
- Energy characteristics of a nonlinear layer at resonant frequencies of wave scattering and generation
- Ion charge separation with new generation of nuclear emulsion films
- On the influence of water on fragmentation of the amino acid L-threonine
- Formulation of heat conduction and thermal conductivity of metals
- Displacement Reliability Analysis of Submerged Multi-body Structure’s Floating Body for Connection Gaps
- Deposits of iron oxides in the human globus pallidus
- Integrability, exact solutions and nonlinear dynamics of a nonisospectral integral-differential system
- Bounds for partition dimension of M-wheels
- Visual Analysis of Cylindrically Polarized Light Beams’ Focal Characteristics by Path Integral
- Analysis of repulsive central universal force field on solar and galactic dynamics
- Solitary Wave Solution of Nonlinear PDEs Arising in Mathematical Physics
- Understanding quantum mechanics: a review and synthesis in precise language
- Plane Wave Reflection in a Compressible Half Space with Initial Stress
- Evaluation of the realism of a full-color reflection H2 analog hologram recorded on ultra-fine-grain silver-halide material
- Graph cutting and its application to biological data
- Time fractional modified KdV-type equations: Lie symmetries, exact solutions and conservation laws
- Exact solutions of equal-width equation and its conservation laws
- MHD and Slip Effect on Two-immiscible Third Grade Fluid on Thin Film Flow over a Vertical Moving Belt
- Vibration Analysis of a Three-Layered FGM Cylindrical Shell Including the Effect Of Ring Support
- Hybrid censoring samples in assessment the lifetime performance index of Chen distributed products
- Study on the law of coal resistivity variation in the process of gas adsorption/desorption
- Mapping of Lineament Structures from Aeromagnetic and Landsat Data Over Ankpa Area of Lower Benue Trough, Nigeria
- Beta Generalized Exponentiated Frechet Distribution with Applications
- INS/gravity gradient aided navigation based on gravitation field particle filter
- Electrodynamics in Euclidean Space Time Geometries
- Dynamics and Wear Analysis of Hydraulic Turbines in Solid-liquid Two-phase Flow
- On Numerical Solution Of The Time Fractional Advection-Diffusion Equation Involving Atangana-Baleanu-Caputo Derivative
- New Complex Solutions to the Nonlinear Electrical Transmission Line Model
- The effects of quantum spectrum of 4 + n-dimensional water around a DNA on pure water in four dimensional universe
- Quantum Phase Estimation Algorithm for Finding Polynomial Roots
- Vibration Equation of Fractional Order Describing Viscoelasticity and Viscous Inertia
- The Errors Recognition and Compensation for the Numerical Control Machine Tools Based on Laser Testing Technology
- Evaluation and Decision Making of Organization Quality Specific Immunity Based on MGDM-IPLAO Method
- Key Frame Extraction of Multi-Resolution Remote Sensing Images Under Quality Constraint
- Influences of Contact Force towards Dressing Contiguous Sense of Linen Clothing
- Modeling and optimization of urban rail transit scheduling with adaptive fruit fly optimization algorithm
- The pseudo-limit problem existing in electromagnetic radiation transmission and its mathematical physics principle analysis
- Chaos synchronization of fractional–order discrete–time systems with different dimensions using two scaling matrices
- Stress Characteristics and Overload Failure Analysis of Cemented Sand and Gravel Dam in Naheng Reservoir
- A Big Data Analysis Method Based on Modified Collaborative Filtering Recommendation Algorithms
- Semi-supervised Classification Based Mixed Sampling for Imbalanced Data
- The Influence of Trading Volume, Market Trend, and Monetary Policy on Characteristics of the Chinese Stock Exchange: An Econophysics Perspective
- Estimation of sand water content using GPR combined time-frequency analysis in the Ordos Basin, China
- Special Issue Applications of Nonlinear Dynamics
- Discrete approximate iterative method for fuzzy investment portfolio based on transaction cost threshold constraint
- Multi-objective performance optimization of ORC cycle based on improved ant colony algorithm
- Information retrieval algorithm of industrial cluster based on vector space
- Parametric model updating with frequency and MAC combined objective function of port crane structure based on operational modal analysis
- Evacuation simulation of different flow ratios in low-density state
- A pointer location algorithm for computer visionbased automatic reading recognition of pointer gauges
- A cloud computing separation model based on information flow
- Optimizing model and algorithm for railway freight loading problem
- Denoising data acquisition algorithm for array pixelated CdZnTe nuclear detector
- Radiation effects of nuclear physics rays on hepatoma cells
- Special issue: XXVth Symposium on Electromagnetic Phenomena in Nonlinear Circuits (EPNC2018)
- A study on numerical integration methods for rendering atmospheric scattering phenomenon
- Wave propagation time optimization for geodesic distances calculation using the Heat Method
- Analysis of electricity generation efficiency in photovoltaic building systems made of HIT-IBC cells for multi-family residential buildings
- A structural quality evaluation model for three-dimensional simulations
- WiFi Electromagnetic Field Modelling for Indoor Localization
- Modeling Human Pupil Dilation to Decouple the Pupillary Light Reflex
- Principal Component Analysis based on data characteristics for dimensionality reduction of ECG recordings in arrhythmia classification
- Blinking Extraction in Eye gaze System for Stereoscopy Movies
- Optimization of screen-space directional occlusion algorithms
- Heuristic based real-time hybrid rendering with the use of rasterization and ray tracing method
- Review of muscle modelling methods from the point of view of motion biomechanics with particular emphasis on the shoulder
- The use of segmented-shifted grain-oriented sheets in magnetic circuits of small AC motors
- High Temperature Permanent Magnet Synchronous Machine Analysis of Thermal Field
- Inverse approach for concentrated winding surface permanent magnet synchronous machines noiseless design
- An enameled wire with a semi-conductive layer: A solution for a better distibution of the voltage stresses in motor windings
- High temperature machines: topologies and preliminary design
- Aging monitoring of electrical machines using winding high frequency equivalent circuits
- Design of inorganic coils for high temperature electrical machines
- A New Concept for Deeper Integration of Converters and Drives in Electrical Machines: Simulation and Experimental Investigations
- Special Issue on Energetic Materials and Processes
- Investigations into the mechanisms of electrohydrodynamic instability in free surface electrospinning
- Effect of Pressure Distribution on the Energy Dissipation of Lap Joints under Equal Pre-tension Force
- Research on microstructure and forming mechanism of TiC/1Cr12Ni3Mo2V composite based on laser solid forming
- Crystallization of Nano-TiO2 Films based on Glass Fiber Fabric Substrate and Its Impact on Catalytic Performance
- Effect of Adding Rare Earth Elements Er and Gd on the Corrosion Residual Strength of Magnesium Alloy
- Closed-die Forging Technology and Numerical Simulation of Aluminum Alloy Connecting Rod
- Numerical Simulation and Experimental Research on Material Parameters Solution and Shape Control of Sandwich Panels with Aluminum Honeycomb
- Research and Analysis of the Effect of Heat Treatment on Damping Properties of Ductile Iron
- Effect of austenitising heat treatment on microstructure and properties of a nitrogen bearing martensitic stainless steel
- Special Issue on Fundamental Physics of Thermal Transports and Energy Conversions
- Numerical simulation of welding distortions in large structures with a simplified engineering approach
- Investigation on the effect of electrode tip on formation of metal droplets and temperature profile in a vibrating electrode electroslag remelting process
- Effect of North Wall Materials on the Thermal Environment in Chinese Solar Greenhouse (Part A: Experimental Researches)
- Three-dimensional optimal design of a cooled turbine considering the coolant-requirement change
- Theoretical analysis of particle size re-distribution due to Ostwald ripening in the fuel cell catalyst layer
- Effect of phase change materials on heat dissipation of a multiple heat source system
- Wetting properties and performance of modified composite collectors in a membrane-based wet electrostatic precipitator
- Implementation of the Semi Empirical Kinetic Soot Model Within Chemistry Tabulation Framework for Efficient Emissions Predictions in Diesel Engines
- Comparison and analyses of two thermal performance evaluation models for a public building
- A Novel Evaluation Method For Particle Deposition Measurement
- Effect of the two-phase hybrid mode of effervescent atomizer on the atomization characteristics
- Erratum
- Integrability analysis of the partial differential equation describing the classical bond-pricing model of mathematical finance
- Erratum to: Energy converting layers for thin-film flexible photovoltaic structures
Articles in the same Issue
- Regular Articles
- Non-equilibrium Phase Transitions in 2D Small-World Networks: Competing Dynamics
- Harmonic waves solution in dual-phase-lag magneto-thermoelasticity
- Multiplicative topological indices of honeycomb derived networks
- Zagreb Polynomials and redefined Zagreb indices of nanostar dendrimers
- Solar concentrators manufacture and automation
- Idea of multi cohesive areas - foundation, current status and perspective
- Derivation method of numerous dynamics in the Special Theory of Relativity
- An application of Nwogu’s Boussinesq model to analyze the head-on collision process between hydroelastic solitary waves
- Competing Risks Model with Partially Step-Stress Accelerate Life Tests in Analyses Lifetime Chen Data under Type-II Censoring Scheme
- Group velocity mismatch at ultrashort electromagnetic pulse propagation in nonlinear metamaterials
- Investigating the impact of dissolved natural gas on the flow characteristics of multicomponent fluid in pipelines
- Analysis of impact load on tubing and shock absorption during perforating
- Energy characteristics of a nonlinear layer at resonant frequencies of wave scattering and generation
- Ion charge separation with new generation of nuclear emulsion films
- On the influence of water on fragmentation of the amino acid L-threonine
- Formulation of heat conduction and thermal conductivity of metals
- Displacement Reliability Analysis of Submerged Multi-body Structure’s Floating Body for Connection Gaps
- Deposits of iron oxides in the human globus pallidus
- Integrability, exact solutions and nonlinear dynamics of a nonisospectral integral-differential system
- Bounds for partition dimension of M-wheels
- Visual Analysis of Cylindrically Polarized Light Beams’ Focal Characteristics by Path Integral
- Analysis of repulsive central universal force field on solar and galactic dynamics
- Solitary Wave Solution of Nonlinear PDEs Arising in Mathematical Physics
- Understanding quantum mechanics: a review and synthesis in precise language
- Plane Wave Reflection in a Compressible Half Space with Initial Stress
- Evaluation of the realism of a full-color reflection H2 analog hologram recorded on ultra-fine-grain silver-halide material
- Graph cutting and its application to biological data
- Time fractional modified KdV-type equations: Lie symmetries, exact solutions and conservation laws
- Exact solutions of equal-width equation and its conservation laws
- MHD and Slip Effect on Two-immiscible Third Grade Fluid on Thin Film Flow over a Vertical Moving Belt
- Vibration Analysis of a Three-Layered FGM Cylindrical Shell Including the Effect Of Ring Support
- Hybrid censoring samples in assessment the lifetime performance index of Chen distributed products
- Study on the law of coal resistivity variation in the process of gas adsorption/desorption
- Mapping of Lineament Structures from Aeromagnetic and Landsat Data Over Ankpa Area of Lower Benue Trough, Nigeria
- Beta Generalized Exponentiated Frechet Distribution with Applications
- INS/gravity gradient aided navigation based on gravitation field particle filter
- Electrodynamics in Euclidean Space Time Geometries
- Dynamics and Wear Analysis of Hydraulic Turbines in Solid-liquid Two-phase Flow
- On Numerical Solution Of The Time Fractional Advection-Diffusion Equation Involving Atangana-Baleanu-Caputo Derivative
- New Complex Solutions to the Nonlinear Electrical Transmission Line Model
- The effects of quantum spectrum of 4 + n-dimensional water around a DNA on pure water in four dimensional universe
- Quantum Phase Estimation Algorithm for Finding Polynomial Roots
- Vibration Equation of Fractional Order Describing Viscoelasticity and Viscous Inertia
- The Errors Recognition and Compensation for the Numerical Control Machine Tools Based on Laser Testing Technology
- Evaluation and Decision Making of Organization Quality Specific Immunity Based on MGDM-IPLAO Method
- Key Frame Extraction of Multi-Resolution Remote Sensing Images Under Quality Constraint
- Influences of Contact Force towards Dressing Contiguous Sense of Linen Clothing
- Modeling and optimization of urban rail transit scheduling with adaptive fruit fly optimization algorithm
- The pseudo-limit problem existing in electromagnetic radiation transmission and its mathematical physics principle analysis
- Chaos synchronization of fractional–order discrete–time systems with different dimensions using two scaling matrices
- Stress Characteristics and Overload Failure Analysis of Cemented Sand and Gravel Dam in Naheng Reservoir
- A Big Data Analysis Method Based on Modified Collaborative Filtering Recommendation Algorithms
- Semi-supervised Classification Based Mixed Sampling for Imbalanced Data
- The Influence of Trading Volume, Market Trend, and Monetary Policy on Characteristics of the Chinese Stock Exchange: An Econophysics Perspective
- Estimation of sand water content using GPR combined time-frequency analysis in the Ordos Basin, China
- Special Issue Applications of Nonlinear Dynamics
- Discrete approximate iterative method for fuzzy investment portfolio based on transaction cost threshold constraint
- Multi-objective performance optimization of ORC cycle based on improved ant colony algorithm
- Information retrieval algorithm of industrial cluster based on vector space
- Parametric model updating with frequency and MAC combined objective function of port crane structure based on operational modal analysis
- Evacuation simulation of different flow ratios in low-density state
- A pointer location algorithm for computer visionbased automatic reading recognition of pointer gauges
- A cloud computing separation model based on information flow
- Optimizing model and algorithm for railway freight loading problem
- Denoising data acquisition algorithm for array pixelated CdZnTe nuclear detector
- Radiation effects of nuclear physics rays on hepatoma cells
- Special issue: XXVth Symposium on Electromagnetic Phenomena in Nonlinear Circuits (EPNC2018)
- A study on numerical integration methods for rendering atmospheric scattering phenomenon
- Wave propagation time optimization for geodesic distances calculation using the Heat Method
- Analysis of electricity generation efficiency in photovoltaic building systems made of HIT-IBC cells for multi-family residential buildings
- A structural quality evaluation model for three-dimensional simulations
- WiFi Electromagnetic Field Modelling for Indoor Localization
- Modeling Human Pupil Dilation to Decouple the Pupillary Light Reflex
- Principal Component Analysis based on data characteristics for dimensionality reduction of ECG recordings in arrhythmia classification
- Blinking Extraction in Eye gaze System for Stereoscopy Movies
- Optimization of screen-space directional occlusion algorithms
- Heuristic based real-time hybrid rendering with the use of rasterization and ray tracing method
- Review of muscle modelling methods from the point of view of motion biomechanics with particular emphasis on the shoulder
- The use of segmented-shifted grain-oriented sheets in magnetic circuits of small AC motors
- High Temperature Permanent Magnet Synchronous Machine Analysis of Thermal Field
- Inverse approach for concentrated winding surface permanent magnet synchronous machines noiseless design
- An enameled wire with a semi-conductive layer: A solution for a better distibution of the voltage stresses in motor windings
- High temperature machines: topologies and preliminary design
- Aging monitoring of electrical machines using winding high frequency equivalent circuits
- Design of inorganic coils for high temperature electrical machines
- A New Concept for Deeper Integration of Converters and Drives in Electrical Machines: Simulation and Experimental Investigations
- Special Issue on Energetic Materials and Processes
- Investigations into the mechanisms of electrohydrodynamic instability in free surface electrospinning
- Effect of Pressure Distribution on the Energy Dissipation of Lap Joints under Equal Pre-tension Force
- Research on microstructure and forming mechanism of TiC/1Cr12Ni3Mo2V composite based on laser solid forming
- Crystallization of Nano-TiO2 Films based on Glass Fiber Fabric Substrate and Its Impact on Catalytic Performance
- Effect of Adding Rare Earth Elements Er and Gd on the Corrosion Residual Strength of Magnesium Alloy
- Closed-die Forging Technology and Numerical Simulation of Aluminum Alloy Connecting Rod
- Numerical Simulation and Experimental Research on Material Parameters Solution and Shape Control of Sandwich Panels with Aluminum Honeycomb
- Research and Analysis of the Effect of Heat Treatment on Damping Properties of Ductile Iron
- Effect of austenitising heat treatment on microstructure and properties of a nitrogen bearing martensitic stainless steel
- Special Issue on Fundamental Physics of Thermal Transports and Energy Conversions
- Numerical simulation of welding distortions in large structures with a simplified engineering approach
- Investigation on the effect of electrode tip on formation of metal droplets and temperature profile in a vibrating electrode electroslag remelting process
- Effect of North Wall Materials on the Thermal Environment in Chinese Solar Greenhouse (Part A: Experimental Researches)
- Three-dimensional optimal design of a cooled turbine considering the coolant-requirement change
- Theoretical analysis of particle size re-distribution due to Ostwald ripening in the fuel cell catalyst layer
- Effect of phase change materials on heat dissipation of a multiple heat source system
- Wetting properties and performance of modified composite collectors in a membrane-based wet electrostatic precipitator
- Implementation of the Semi Empirical Kinetic Soot Model Within Chemistry Tabulation Framework for Efficient Emissions Predictions in Diesel Engines
- Comparison and analyses of two thermal performance evaluation models for a public building
- A Novel Evaluation Method For Particle Deposition Measurement
- Effect of the two-phase hybrid mode of effervescent atomizer on the atomization characteristics
- Erratum
- Integrability analysis of the partial differential equation describing the classical bond-pricing model of mathematical finance
- Erratum to: Energy converting layers for thin-film flexible photovoltaic structures