Publication Cover
Numerical Heat Transfer, Part A: Applications
An International Journal of Computation and Methodology
Volume 70, 2016 - Issue 6
330
Views
16
CrossRef citations to date
0
Altmetric
Original Articles

Effects of deposition height and width on film cooling

, , &
Pages 673-687 | Received 10 Jan 2016, Accepted 20 Apr 2016, Published online: 18 Aug 2016
 

ABSTRACT

Because natural gas resources continue to be depleted for usage of gas turbines, it becomes important to search for alternate fuels. Coal-derived synthetic fuels contain traces of ash and other contaminants that result in deposition on vane and turbine surfaces. The present research shows a comparison of simulated results with and without a deposition configuration. Film cooling effectiveness distribution after the deposition was obtained to investigate the effects of various deposition heights and widths under the blowing ratios of 0.5, 0.75, and 1.0. The results indicated that the deposition near the hole exit can weaken the cooling performance. Moreover, it is revealed that the film cooling effectiveness deteriorates with increased deposition heights. The deposition width study revealed that a narrow deposition shows a good attachment of the coolant jet to the wall surface. It is found that an improvement of the film cooling effectiveness can be obtained by decreasing the blowing ratio.

Nomenclature

d=

film hole throat diameter (mm)

h=

height of deposition (mm)

k=

turbulence kinetic energy (m2/s2)

M=

blowing ratio (= ρjVj/ρV)

P=

pressure (N/m2)

T=

temperature (K)

u=

streamwise velocity component (m/s)

V=

velocity magnitude (m/s)

w=

width of deposition (mm)

x, y, z=

coordinate direction distance (m)

α=

inclination angle (°)

ϵ=

turbulence dissipation rate

η=

adiabatic film cooling effectiveness (= Taw − Ti)/(Tj − Ti)

λ=

heat conductivity (W/mK)

θ=

nondimensional temperature (= T − Ti)/(Tj − Ti)

ρ=

density (kg/m3)

τ=

stress tensor (kg/m s2)

Subscripts=
a=

area average value

aw=

adiabatic wall

c=

centerline

i=

mainstream flow

j=

coolant jet

t=

turbulent

Nomenclature

d=

film hole throat diameter (mm)

h=

height of deposition (mm)

k=

turbulence kinetic energy (m2/s2)

M=

blowing ratio (= ρjVj/ρV)

P=

pressure (N/m2)

T=

temperature (K)

u=

streamwise velocity component (m/s)

V=

velocity magnitude (m/s)

w=

width of deposition (mm)

x, y, z=

coordinate direction distance (m)

α=

inclination angle (°)

ϵ=

turbulence dissipation rate

η=

adiabatic film cooling effectiveness (= Taw − Ti)/(Tj − Ti)

λ=

heat conductivity (W/mK)

θ=

nondimensional temperature (= T − Ti)/(Tj − Ti)

ρ=

density (kg/m3)

τ=

stress tensor (kg/m s2)

Subscripts=
a=

area average value

aw=

adiabatic wall

c=

centerline

i=

mainstream flow

j=

coolant jet

t=

turbulent

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 61.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 716.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.