Investigation on the Effect of Different Lands on Trailing Edge Slot Film Cooling
-
Yang Xu
,
Wei-jiang Xu
Abstract
Trailing edge slot film cooling is a widely used method for protecting the trailing edge of turbine blades from hot gas impingement. The structures that separate the slots, known as “lands,” come in a variety of configurations. This paper presents the effects of the trailing edge with different lands on the film cooling performance. Experimental studies are conducted on the film cooling effectiveness and Nusselt number with different lands. Four trailing edge configurations, including the straight lands, the beveling lands, the fillet lands and the tapered lands are considered under four blowing ratios (0.5, 0.7, 1.0 and 1.5). The Reynolds numbers of mainstream is fixed as 375,000. Film cooling effectiveness and Nusselt number performances are measured by transient liquid crystal measurement technique. Reynolds-averaged Navier-Stokes (RANS) simulation with realizable k-ε turbulence model and enhanced wall functions are performed using a commercial code Fluent. In each case, the slot height is kept constant. It is shown that the beveling lands, the fillet lands and the tapered lands have higher cooling effectiveness and lower Nusselt number compared with the straight lands. Under higher blowing ratios, the trailing edges of all four lands have higher cooling effectiveness and higher Nusselt number.
Nomenclature
- h
heat transfer coefficient (
- H
slot height (m)
- L
distance from the beginning of boundary layer formation to bleeding slot (m)
mass flow rate (
- M
blowing ratio (=
- Nu
Nusselt number, the characteristic dimension
- Re
Reynolds number
- t
time (s)
- T
temperature (K)
- U
velocity (
- X
streamwise coordinate (m)
- Y
spanwise coordinate (m)
- Z
normal coordinate (m)
- Greek symbols
film cooling effectiveness
- Y
spanwise coordinate (m)
density (
dynamic viscosity (
density (
thermal conductivity of wall (
non-dimensional temperature
- Subscripts
- aw
adiabatic wall
- c
secondary flow
- g
mainstream
- i
mainstream
- s
surface
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© 2018 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Effect of orifice spacing on twin circular parallel compressible jets
- Design and Experiment of Casing Treatment for a Centrifugal Compressor
- An Integrated Throughflow Method for the Performance Analysis of Variable Cycle Compression Systems
- Aerodynamic Performance Characteristics of NACA 0010 Cascade with Gurney Flaps
- Study on a Quasi-Two-Dimensional Fan Model for Variant Bypass-Ratio Condition
- Co-Flowing Jet Control Using Lip Thickness Variation
- Investigation on the Effect of Different Lands on Trailing Edge Slot Film Cooling
- Installation Characteristics of Variable Cycle Engine Based on Inlet Flow Matching
- Supersonic Jet Control by Tabs with Slanted Perforation
- Effect of Injection Angle on Performance of Full Coverage Film Cooling with Opposite Injection Holes
Articles in the same Issue
- Frontmatter
- Effect of orifice spacing on twin circular parallel compressible jets
- Design and Experiment of Casing Treatment for a Centrifugal Compressor
- An Integrated Throughflow Method for the Performance Analysis of Variable Cycle Compression Systems
- Aerodynamic Performance Characteristics of NACA 0010 Cascade with Gurney Flaps
- Study on a Quasi-Two-Dimensional Fan Model for Variant Bypass-Ratio Condition
- Co-Flowing Jet Control Using Lip Thickness Variation
- Investigation on the Effect of Different Lands on Trailing Edge Slot Film Cooling
- Installation Characteristics of Variable Cycle Engine Based on Inlet Flow Matching
- Supersonic Jet Control by Tabs with Slanted Perforation
- Effect of Injection Angle on Performance of Full Coverage Film Cooling with Opposite Injection Holes
