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Heat Transfer Characteristics of Nitrogen in Supercritical Region Using Redlich-Kwong Equation of State

  • Hussain Basha , G. Janardhana Reddy EMAIL logo und N. S. Venkata Narayanan
Veröffentlicht/Copyright: 18. Juli 2019

Abstract

The present paper studies through numerical methods, the thermodynamic heat transfer characteristics of free convection flow of supercritical nitrogen over a vertical cylinder. In the present analysis, the values of volumetric thermal expansion coefficient (β) are evaluated based on Redlich-Kwong equation of state (RK-EOS) and Van der Waals equation of state (VW-EOS). The calculated analytical thermal expansion coefficient values using RK-EOS are very close to NIST data values in comparison with VW-EOS. A set of coupled nonlinear partial differential equations (PDEs) governing the supercritical fluid (SCF) flow are derived, converted into non-dimensional form with the help of suitable dimensionless quantities and solved using Crank-Nicolson implicit finite difference method. The simulations are carried out for nitrogen in the supercritical region. The obtained numerical data is expressed in terms of graphs and tables for various values of physical parameters. The increasing value of reduced temperature decreases the average Nusselt number and skin-friction coefficient, whereas amplifying value of reduced pressure enhance the heat transfer rate and wall shear stress in the SCF region. Present results are compared with the previous results and the two are found to be in good agreement, i. e. the numerically generated results found to be in agreement with existing results.

Acknowledgements

The first author Hussain Basha wishes to thank Maulana Azad National Fellowship program, University Grants Commission, Government of India, Ministry of Minority Affairs, MANF (F1-17.1/2017-18/MANF-2017-18-KAR-81943) for the grant of research fellowship and to Central University of Karnataka for providing the research facilities. Further, the authors are very much thankful to all four reviewers for their valuable suggestions and comments to improve the quality of the manuscript.

A Appendix

Table 4:

Thermal expansion coefficient (β) values based on RK-EOS (Soave 1993), VW-EOS (Blundell and Blundell 2006), NIST database (NIST (National Institute of Standards and Technology)) ideal gas assumption (Poling, Prausnitz, and O’Connell 2001) for different values of reduced pressure (Pr) and reduced temperature (Tr) in SCF region.

P56789
Pr1.471.762.062.352.65
T200230260290340
Tr1.581.822.062.292.69
A  RK-EOS0.1990440.1684160.1446160.1257900.095082
B0.0804720.0839710.0866620.0887970.085206
Z0.8947240.9333110.9610820.9819401.005412
β0.007357830.005772160.004762300.004060620.00325637
A  VW-EOS0.2472950.2243880.2048590.1881910.154024
B0.1161280.1211770.1250610.1281420.122959
Z0.8697670.9067920.9353210.9579720.986259
β0.007560080.005993070.004963630.004235800.00338444
β  NIST Data0.006979800.005560510.004627250.003964660.00319153
β  Ideal Gas0.0050000000.004347820.003846150.0034482700.00294117
Table 5:

Time to reach temporal maxima of flow variables, steady-state and maximum velocity at X=1.0 with various values of Pr and Tr for supercritical nitrogen.

Temporal maximum (t) ofSteady-stateMaximum
PrTrUθtime (t)velocity at X = 1
1.471.901.751.668.211.3009
1.761.491.427.581.5650
2.061.281.217.081.8219
2.351.161.086.672.0668
2.651.061.016.342.2984
1.761.580.920.885.942.6385
1.821.331.247.191.7572
2.061.791.728.321.2628
2.292.342.239.330.9535
2.693.463.2610.870.6437
Table 6:

Average skin-friction coefficient (C¯f) and Nusselt number (Nu¯) for different values of Pr and Tr for nitrogen in supercritical region.

PrTrC¯fNu¯
1.471.904.16121.5603
1.765.44261.6821
2.066.78981.7926
2.358.17161.8933
2.659.54841.9845
1.761.5811.84932.1497
1.826.45841.7720
2.063.98201.5393
2.292.65681.3785
2.691.51721.1921

B Assumption of incompressible fluid and the applicability of the Boussinesq’s approximation to supercritical fluids

For the flows satisfying certain conditions, Boussinesq’s in 1903 suggested that density changes in the fluid can be neglected except where ρ is multiplied by g. A formal justification, and the conditions under which the Boussinesq’s approximation holds for supercritical fluids, is given here (Kundu, Cohen, and Dowling 2012; Teymourtash, Khonakdar, and Raveshi 2013). The more general form of the continuity equation is as follows:

(13)1ρDρDt+.U=0

With the help of Boussinesq’s approximation, the incompressible continuity equation can be rewritten in the following form:

(14).U=0

This does not mean that a constant value of density. Here neglecting the term ρ1(DρDt) is just due to its small scale compared to velocity gradients in the term .U. Based on the scaling analysis it is found that ρ1(DρDt) is small when compared to the velocity gradient terms in .U.

Now consider a situation that compressibility effects are negligible and density variation is just due to temperature changes. This is the governing case in convective heat transfer problems. In this case, the variation of density among temperature is as follows:

(15)δρρ=βδT where β=1ρ(δρδT)

In this equation, β is thermal expansion coefficient at constant pressure and varies proportional to (1T) for ideal gas. To show the reason of neglecting the term ρ1(DρDt) in continuity equation compared to velocity gradient terms, it is necessary to use scale analysis. To see this, we assume that the flow field is characterized by a length scale L, a velocity scale U, and a temperature scale δT. By this we mean that the velocity varies by U and the temperature varies by δT between locations separated by a distance of order L. The ratio of the magnitudes of the two terms in the continuity equation is

(16)1ρ(DρDt).U(1ρ)u(ρt)ux(Uρ)(δρL)UL=δρρ=βδT1

The above eq. (16) is valid since, for smaller temperature difference, the thermal expansion coefficient is smaller. Therefore the first term can be omitted in comparison with second term in the eq. (13). On the other hand, Figure 17(a) and (b) describe that, for the temperature difference of 3.78 K near the critical point gives the maximum value of 0.003 for βδT which satisfies the eq. (16). Also, throughout the graph far away from the critical point the above condition is valid for different temperature differences δT. As a result, the Boussinesq’s approximation is completely valid in supercritical region. Finally, eq. (13) can be reduced to eq. (14).

Figure 17: (a) Thermal expansion coefficient $\left( \beta \right)$(β) and its slope for nitrogen at $P_r^*\,=\,1.77$Pr∗=1.77 using RK-EOS, (b) enlarged view.
Figure 17:

(a) Thermal expansion coefficient (β) and its slope for nitrogen at Pr=1.77 using RK-EOS, (b) enlarged view.

Now let’s consider the case, if the fluid density (ρ) be assumed as a function of pressure and temperature, then it is possible to expand ρ(P,T) and formulate it as environment density ρ(P,T) in a second-order Taylor series expansion:

(17)ρ=ρ+(TT) (ρT)P+12(TT)2(2ρT2)P+.+(PP) (ρP)T+12(PP)2(2ρP2)T++(TT)(PP)(2ρTP)+

Thermal expansion coefficient (β) equation has been expressed as follows:

(18)β=1ρ(ρT)P

Here (2ρT2)P can be obtained as:

Since from the eq. (18) we have

(19)(ρT)P=βρ

Differentiating eq. (19) w.r.t T, we get

(20)(2ρT2)P=ρ(βT)Pβ(ρT)P

Using eq. (19) in eq. (20), we get

(21)(2ρT2)P=ρ(βT)P+ρβ2

Since it is assumed that, the vertical length is small and the corresponding pressure loss is small too, so:

(22)(PP)0

Replacing eq. (22) in eq. (17) results in:

(23)ρρ=ρβ(TT)+12 ρβ2(TT)2 12 ρ(TT)2(βT)P+.

It can be seen that if temperature differences are small, the term β(TT) is less than 1 and just the first term in right hand side will remain in the equation. Figure 18(a) and (b), show the range of temperature gradient in which the second and third terms of eq. (23) can be neglected. These figures are plotted at Pr=2.09 and Pr=2.19. Finally, eq. (23) has been reduced to eq. (24), and hence Boussinesq’s approximation is reliable in supercritical region.

(24)ρρ=ρβ(TT)
Figure 18: The magnitude of different terms of eq. (23) for supercritical nitrogen at (a) $P_r^*\,=\,2.09$Pr∗=2.09, $T_r^*\,=\,1.40$Tr∗=1.40, (b) $P_r^*\,=\,2.19$Pr∗=2.19, $T_r^*\,=\,1.40$Tr∗=1.40 using RK-EOS.
Figure 18:

The magnitude of different terms of eq. (23) for supercritical nitrogen at (a) Pr=2.09, Tr=1.40, (b) Pr=2.19, Tr=1.40 using RK-EOS.

References

Arai, Y., T. Sako, and Y. Takebayashi. 2002. Supercritical Fluids, 1st ed. Berlin Heidelberg: Springer-verlag.10.1007/978-3-642-56238-9Suche in Google Scholar

Blundell, S. J., and K. M. Blundell. 2006. Concepts in Thermal Physics. UK: Oxford University Press.Suche in Google Scholar

Brunner, G. 1994. Topics in Physical Chemistry: Gas Extraction. Berlin Heidelberg: Springer-Verlag.10.1007/978-3-662-07380-3Suche in Google Scholar

Carton, O., D. B. Salem, S. Bhatt, J. Pulpytel, and F. A. Khonsari. 2012. “Plasma Polymerization of Acrylic Acid by Atmospheric Pressure Nitrogen Plasma Jet for Biomedical Applications.” Plasma Processes and Polymers 9: 984–93.10.1002/ppap.201200044Suche in Google Scholar

Domingo, C., and P. S. Peternault. 2016. Supercritical Fluid Nanotechnology. USA: CRC press Taylor and Francis group.Suche in Google Scholar

Dondapati, R. S., J. Ravula, S. Thadela, and P. R. Usurumarti. 2015. “Analytical Approximations for Thermophysical Properties of Supercritical Nitrogen (SCN) to Be Used in Futuristic High Temperature Superconducting (HTS) Cables.” Physica C: Superconductivity and Its Applications 519: 53–59.10.1016/j.physc.2015.08.005Suche in Google Scholar

Ede, A. J. 1967. Advances in Free Convection. East Kilbride, Scotland, UK: National Engineering Laboratory.10.1016/S0065-2717(08)70272-7Suche in Google Scholar

Fages, J., H. Lochard, J. J. Letourneau, M. Sauceau, and E. Rodier. 2004. “Particle Generation for Pharmaceutical Applications Using Supercritical Fluid Technology.” Powder Technology 141: 219–26.10.1016/j.powtec.2004.02.007Suche in Google Scholar

Ghaderi, R., P. Artursson, and J. Carlfors. 2000. “A New Method for Preparing Biodegradable Microparticles and Entrapment of Hydrocortisone in DL-PLG Micro Particles Using Supercritical Fluids.” European Journal of Pharmaceutical Sciences 10 (1): 1–9.10.1016/S0928-0987(99)00079-2Suche in Google Scholar

Goodship, V., and E. O. Ogur. 2004. Polymer Processing with Supercritical Fluids. USA: Rapra Review Reports.Suche in Google Scholar

Hahne, E. W. P. 1968. “Natural Convection Heat Transfer through an Enclosed Horizontal Layer of Supercritical Carbon Dioxide.” International Journal of Heat and Mass Transfer 1 (3): 190–96.10.1007/BF00751151Suche in Google Scholar

Heck, R. M. 1999. “Catalytic Abatement of Nitrogen Oxides-Stationary Applications.” Catalysis Today 53: 519–23.10.1016/S0920-5861(99)00139-XSuche in Google Scholar

Herrer, M., J. A. Mendiola, A. Cifuentes, and E. Ibanez. 2010. “Supercritical Fluid Extraction: Recent Advances and Applications.” Journal of Chromatography A 1217: 2495–511.10.1016/j.chroma.2009.12.019Suche in Google Scholar PubMed

Khonakdar, D. R., and M. R Raveshi. 2016. “Mixed Convection on a Vertical Plate in Supercritical Fluids by Selecting the Best Equation of State.” The Journal of Supercritical Fluids 107: 549–59.10.1016/j.supflu.2015.07.013Suche in Google Scholar

Killilea, W. R., K. C. Swallow, and G. T. Hong. 1992. “The Fate of Nitrogen in Supercritical-Water Oxidation.” The Journal of Supercritical Fluids 5: 72–78.10.1016/0896-8446(92)90044-KSuche in Google Scholar

Kim, T., Y. Kim, and S. K. Kim. 2011. “Numerical Study of Cryogenic Liquid Nitrogen Jets at Supercritical Pressures.” The Journal of Supercritical Fluids 56: 152–63.10.1016/j.supflu.2010.12.008Suche in Google Scholar

Kimmel, D. B. 2007. “Mechanism of Action, Pharmacokinetic and Pharmacodynamic Profile, and Clinical Applications of Nitrogen-Containing Bisphosphonates.” Journal of Dental Research 86 (11): 1022–33.10.1177/154405910708601102Suche in Google Scholar

Kiran, E., P. G. Debenedetti, and C. J. Peters. 2000. Supercritical Fluids: Fundamental and Applications, NATO science series. Dordrecht, Netherlands: Kluwer Academic Publishers.10.1007/978-94-011-3929-8Suche in Google Scholar

Kundu, P. K., I. M. Cohen, and D. R. Dowling. 2012. Fluid Mechanics, 5th ed. USA: Academic Press.Suche in Google Scholar

Lee, H. R., T. S. Chen, and B. F. Armaly. 1988. “Natural Convection along Slender Vertical Cylinders with Variable Surface Temperature.” Journal of Heat Transfer 110 (1): 103–08.10.1115/1.3250439Suche in Google Scholar

Mathiasson, L., J. A. Jonsson, and L. Karlsson. 1989. “Determination of Nitrogen Compounds by Supercritical Fluid Chromatography Using Nitrous Oxide as the Mobile Phase and Nitrogen-Sensitive Detection.” Journal of Chromatography A 467: 61–74.10.1016/S0021-9673(01)93952-4Suche in Google Scholar

McHugh, M. A., and V. J. Krukonis. 1994. Supercritical Fluid Extraction, Principles and Practice, 2nd ed. Boston: Butterworth-Heinemann.Suche in Google Scholar

Miller, R. S., K. G. Harstad, and J. Bellan. 2001. “Direct Numerical Simulations of Supercritical Fluid Mixing Layers Applied to Heptane-Nitrogen.” Journal of Fluid Mechanics 436: 1–39.10.1017/S0022112001003895Suche in Google Scholar

Muller, E. A., and L. A. Estevez. 1990. “Mixing Expansivities and Grashof Number in Supercritical Fluids Using Cubic Equations-Of-State.” The Journal of Supercritical Fluids 3: 136–42.10.1016/0896-8446(90)90038-NSuche in Google Scholar

Nakano, A., M. Shiraishi, and M. Murakami. 2001. “Application of Laser Holography Interferometer to Heat Transfer Phenomena near the Critical Point of Nitrogen.” Cryogenics 41: 429–35.10.1016/S0011-2275(01)00085-6Suche in Google Scholar

Neumann, R. J., and E. W. P. Hahne. 1980. “Free Convective Heat Transfer to Supercritical Carbon Dioxide.” International Journal of Heat and Mass Transfer 23 (12): 1643–52.10.1016/0017-9310(80)90223-9Suche in Google Scholar

Nishikawa, K., and T. Ito. 1969. “An Analysis of Free-Convective Heat Transfer from an Isothermal Vertical Plate to Supercritical Fluids.” International Journal of Heat and Mass Transfer 12: 1449–63.10.1016/0017-9310(69)90027-1Suche in Google Scholar

Nishikawa, K., T. Ito, and H. Yamashita. 1973. “Free-Convective Heat Transfer to a Supercritical Fluid.” Journal of Heat Transfer 95 (2): 187–91.10.1115/1.3450024Suche in Google Scholar

NIST (National Institute of Standards and Technology). Chemistry Web Book (http://webbook.nist.gov/chemistry/fluid/).Suche in Google Scholar

Okongo, N. A., and J. Bellan. 2002. “Direct Numerical Simulation of a Transitional Supercritical Binary Mixing Layer Heptane and Nitrogen.” Journal of Fluid Mechanics 464: 1–34.10.1017/S0022112002008480Suche in Google Scholar

Pallares, J. S., M. T. P. Santos, J. G. Serna, F. Castro, and M. J. Cocero. 2009. “Numerical Analysis of High-Pressure Fluid Jets: Application to RTD Prediction in Supercritical Reactors.” The Journal of Supercritical Fluids 49: 249–55.10.1016/j.supflu.2009.01.009Suche in Google Scholar

Plotka, J. M., M. Biziuk, C. Morrison, and J. Namiesnik. 2014. “Pharmaceutical and Forensic Drug Applications of Chiral Supercritical Fluid Chromatography.” Trends in Analytical Chemistry 56: 74–89.10.1016/j.trac.2013.12.012Suche in Google Scholar

Poling, B. E., J. M. Prausnitz, and J. P. O’Connell. 2001. The Properties of Gases and Liquids, 5th ed. New York: McGraw-Hill.Suche in Google Scholar

Reddy, G. J., H. Basha, and N. S. V. Narayanan. 2018a. “A Numerical Investigation of Transient Natural Convective Heat Transfer to Isobutane in the Supercritical Region.” Journal of Molecular Liquids 250: 131–49.10.1016/j.molliq.2017.11.074Suche in Google Scholar

Reddy, G. J., H. Basha, and N. S. V. Narayanan. 2018b. “Transient Natural Convection Heat Transfer to CO2 in the Supercritical Region.” Journal of Heat Transfer 140: 092502–10.10.1115/1.4039905Suche in Google Scholar

Rolando, A. 2004. Natural convection heat transfer in supercritical fluids. M.Sc. Thesis, Mechanical Engineering, University of Puerto Rico.Suche in Google Scholar

Schmidt, G., and H. Wenzel. 1980. “A Modified Van Der Waals Type Equation of State.” Chemical Engineering Science 35 (7): 1503–12.10.1016/0009-2509(80)80044-3Suche in Google Scholar

Sievers, R. E., B. P. Quinn, S. P. Cape, J. A. Searles, C. S. Braun, P. Bhagwat, L. G. Rebits, et al. 2007. “Near-Critical Fluid Micronization of Stabilized Vaccines, Antibiotics and Anti-Virals.” The Journal of Supercritical Fluids 42: 385–91.10.1016/j.supflu.2007.03.001Suche in Google Scholar

Soave, G. 1993. “20 Years of Redlich-Kwong Equation of State.” Fluid Phase Equilibria 82: 345–59.10.1016/0378-3812(93)87158-WSuche in Google Scholar

Span, R., E. W. Lemmon, R. T. Jacobsen, W. Wagner, and A. Yokozeki. 2000. “A Reference Equation of State for the Thermodynamic Properties of Nitrogen for Temperatures from 63.151 to 1000 K and Pressures to 2200 MPa.” Journal of Physical and Chemical Reference Data 29 (6): 1361–433.10.1063/1.1349047Suche in Google Scholar

Sparrow, E. M., and J. L. Gregg. 1956. “Laminar Free Convection Heat Transfer from the Outer Surface of a Vertical Circular Cylinder.” Journal of Heat Transfer 78 (8): 1823–29.10.1115/1.4014194Suche in Google Scholar

Stadie, N. P., E. Callini, P. Mauron, A. Borgschulte, and A. Zuttel. 2015. “Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials.” Journal of Visualized Experiments 99: 1–9.10.3791/52817Suche in Google Scholar PubMed PubMed Central

Talha, M., C. K. Behera, and O. P. Sinha. 2013. “A Review on Nickel-Free Nitrogen Containing Austenitic Stainless Steels for Biomedical Applications.” Materials Science and Engineering C 33: 3563–75.10.1016/j.msec.2013.06.002Suche in Google Scholar PubMed

Teymourtash, A. R., D. R. Khonakdar, and M. R. Raveshi. 2013. “Natural Convection on a Vertical Plate with Variable Heat Flux in Supercritical Fluids.” The Journal of Supercritical Fluids 74: 115–27.10.1016/j.supflu.2012.12.010Suche in Google Scholar

Zappoli, B., S. Amiroudine, P. Carles, and J. Ouazzani. 1996. “Thermo-Acoustic and Buoyancy Driven Transport in a Square Side-Heated Cavity Filled with a Near-Critical Fluid.” Journal of Fluid Mechanics 316: 53–72.10.1017/S0022112096000444Suche in Google Scholar

Zhou, L., Y. Zhou, S. Bai, C. Lu, and B. Yang. 2001. “Determination of the Adsorbed Phase Volume and Its Application in Isotherm Modelling for the Adsorption of Supercritical Nitrogen on Activated Carbon.” Journal of Colloid and Interface Science 239: 33–38.10.1006/jcis.2001.7514Suche in Google Scholar PubMed

Received: 2018-10-20
Revised: 2019-03-12
Accepted: 2019-03-26
Published Online: 2019-07-18

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