Numerical Investigation on the Effects of Vortex Generator Locations on Film Cooling Performance
-
Daren Zheng
and
Qi Yuan
Abstract
Described in this paper is a numerical investigation on the concept for enhancing film cooling performance by placing vortex generator (VG) upstream the film hole. Six film cooling configurations with different VG locations are investigated, including the distances for VG upstream the film hole (Upstream Distances) of 20 mm, 25 mm, and 30 mm and the VG gaps of 0, 2 mm, 4 mm and 6 mm respectively. The effect of VG locations on film cooling performance were conducted. The film cooling performance is evaluated at the density of 0.97 with the blowing ratio of 1.0. Results obtained show that the twisted flow generated by upstream VG rotates in the opposite direction of kidney vortex, producing an adverse effect on kidney vortex. The enhanced adverse effect could dramatically improve the film cooling performance. Moreover, the intensity of twisted flow is greatly related to the VG locations. The film cooling performance improves with the increasing upstream distances. The film cooling performance improves first and then impairs with increasing VG gaps. In this case, the film cooling performance in the case with gap of 4 mm is superior to those in other cases.
Nomenclature
- Cp
-
static pressure coefficient, (p-p 1)/0.5ρ 1 u 1 2, –
- D
-
diameter of film cooling hole, m
- DR
-
density ratio of coolant to mainstream, ρc /ρm , –
- H
-
VG height, m
- L
-
VG length, m
- M
-
blowing ratios, DR·uc /um , –
- p
-
pressure of the flow, Pa
- Tc
-
coolant temperature, K
- Tm
-
mainstream temperature, K
- Tu
-
mainstream turbulence intensity, –
- um
-
velocity of mainstream, m/s
- u1
-
velocity at mainstream outlet, m/s
- W
-
VG width, m
- x
-
streamwise coordinate along model surface, m
- y
-
spanwise coordinate, m
- z
-
vertical coordinate, m
- Greek letter
- ρ
-
density, kg/m3
- η
-
adiabatic cooling effectiveness, (Taw-Tm)/(Tc-Tm ), –
- θ
-
non-dimensional temperature, (T-Tm)/(Tc-Tm ), –
- ωZ
-
vorticity, –
- Subscripts
- m
-
mainstream
- c
-
coolant
- av
-
average
- aw
-
adiabatic wall
- 1
-
mainstream inlet
Acknowledgements
The authors gratefully acknowledge the support of China Scholarship Council (CSC).
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© 2019 Walter de Gruyter GmbH, Berlin/Boston
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- Frontmatter
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- A new compilation method of general standard test load spectrum for aircraft engine
- Numerical Investigation on the Effects of Vortex Generator Locations on Film Cooling Performance
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- Surplus Power Approach to Diagnose Gas Turbine Engine Starting Characteristics
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- Investigations of Combustor Inlet Swirl on the Liner Wall Temperature in an Aero Engine Combustor
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Articles in the same Issue
- Frontmatter
- Original Research Articles
- Robust Fault Identification of Turbofan Engines Sensors Based on Fractional-Order Integral Sliding Mode Observer
- A new compilation method of general standard test load spectrum for aircraft engine
- Numerical Investigation on the Effects of Vortex Generator Locations on Film Cooling Performance
- The Effect of the Circumferential Position of Duct Hole on the Non-uniformity in the Axial Compressor
- Surplus Power Approach to Diagnose Gas Turbine Engine Starting Characteristics
- A Flow Dynamic Characteristic Analysis of A Single Radial Swirler Combustor
- Investigation on the Jet Stiffness Characteristics of a Novel Plasma Igniter
- Investigations of Combustor Inlet Swirl on the Liner Wall Temperature in an Aero Engine Combustor
- Multidisciplinary Design Optimization of the Composite Cooling Structure for Nickel-based Alloy Turbine Blade
- Experimental Study of Non-Premixed Flames of Liquefied Petroleum Gas and Air in Cross-Flow and the Effects of Fuel Properties on Flame Stability
