Analysis of the influence of cooling hole arrangement on the protection of a gas turbine combustor liner

Meccanica ◽  
2018 ◽  
Vol 53 (9) ◽  
pp. 2257-2271 ◽  
Author(s):  
Ahlem Ben Sik Ali ◽  
Wassim Kriaa ◽  
Hatem Mhiri ◽  
Philippe Bournot
Keyword(s):  
Gas Turbine ◽  
Gas Turbine Combustor ◽  
Cooling Hole ◽  
Combustor Liner

Effects of Effusion Cooling Pattern Near the Dilution Hole for a Double-Walled Combustor Liner: Part 2 — Flowfield Measurements

2018 ◽  
Author(s):  
Adam C. Shrager ◽  
Karen A. Thole ◽  
Dominic Mongillo
Keyword(s):  
Leading Edge ◽  
Freestream Turbulence ◽  
Gas Turbine Combustor ◽  
Impingement Cooling ◽  
Cooling Pattern ◽  
Image Velocimetry ◽  
Cooling Hole ◽  
Difficult Challenge ◽  
Combustor Liner ◽  
Double Wall

The complex flowfield inside a gas turbine combustor creates a difficult challenge in cooling the combustor walls. Many modern combustors are designed with a double-wall that contain both impingement cooling on the backside of the wall and effusion cooling on the external side of the wall. Complicating matters is the fact that these double-walls also contain large dilution holes whereby the cooling film from the effusion holes is interrupted by the high-momentum dilution jets. Given the importance of cooling the entire panel, including the metal surrounding the dilution holes, the focus of this paper is understanding the flow in the region near the dilution holes. Near-wall flowfield measurements are presented for three different effusion cooling hole patterns near the dilution hole. The effusion cooling hole patterns were varied in the region near the dilution hole and include: no effusion holes; effusion holes pointed radially outward from the dilution hole; and effusion holes pointed radially inward toward the dilution hole. Particle image velocimetry (PIV) was used to capture the time-averaged flowfield at approaching freestream turbulence intensities of 0.5% and 13%. Results showed evidence of downward motion at the leading edge of the dilution hole for all three effusion hole patterns. In comparing the three geometries, the outward effusion holes showed significantly higher velocities toward the leading edge of the dilution jet relative to the other two geometries. Although the flowfield generated by the dilution jet dominated the flow downstream, each cooling hole pattern interacted with the flowfield uniquely. Approaching freestream turbulence did not have a significant effect on the flowfield.

Numerical Investigation of Gas Turbine Combustor Liner Film Cooling Slots

2018 ◽  
Author(s):  
Firat Kiyici ◽  
Ahmet Topal ◽  
Ender Hepkaya ◽  
Sinan Inanli
Keyword(s):  
Heat Transfer ◽  
Prandtl Number ◽  
Surface Temperature ◽  
Gas Turbine ◽  
Film Cooling ◽  
Turbulent Prandtl Number ◽  
Surface Cooling ◽  
Gas Turbine Combustor ◽  
Cooling Effectiveness ◽  
Combustor Liner

A numerical study, based on experimental work of Inanli et al. [1] is conducted to understand the heat transfer characteristics of film cooled test plates that represent the gas turbine combustor liner cooling system. Film cooling tests are conducted by six different slot geometries and they are scaled-up model of real combustor liner. Three different blowing ratios are applied to six different geometries and surface cooling effectiveness is determined for each test condition by measuring the surface temperature distribution. Effects of geometrical and flow parameters on cooling effectiveness are investigated. In this study, Conjugate Heat Transfer (CHT) simulations are performed with different turbulence models. Effect of the turbulent Prandtl Number is also investigated in terms of heat transfer distribution along the measurement surface. For this purpose, turbulent Prandtl number is calculated with a correlation as a function of local surface temperature gradient and its effect also compared with the constant turbulent Prandtl numbers. Good agreement is obtained with two-layered k–ϵ with modified Turbulent Prandtl number.

Experimental Assessment of the Emissions Benefits of a Ceramic Gas Turbine Combustor

1996 ◽  
Author(s):  
K. O. Smith ◽  
A. Fahme
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Flow Distribution ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Fuel Injector ◽  
Gas Turbine Combustor ◽  
Experimental Assessment ◽  
Industrial Gas Turbine ◽  
Combustor Liner

Three subscale, cylindrical combustors were rig tested on natural gas at typical industrial gas turbine operating conditions. The intent of the testing was to determine the effect of combustor liner cooling on NOx and CO emissions. In order of decreasing liner cooling, a metal louvre-cooled combustor, a metal effusion-cooled combustor, and a backside-cooled ceramic (CFCC) combustor were evaluated. The three combustors were tested using the same lean-premixed fuel injector. Testing showed that reduced liner cooling produced lower CO emissions as reaction quenching near the liner wall was reduced. A reduction in CO emissions allows a reoptimization of the combustor air flow distribution to yield lower NOx emissions.

Effects of Effusion Cooling Pattern Near the Dilution Hole for a Double-Walled Combustor Liner—Part 1: Overall Effectiveness Measurements

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Adam C. Shrager ◽  
Karen A. Thole ◽  
Dominic Mongillo
Keyword(s):  
Momentum Flux ◽  
Freestream Turbulence ◽  
Complex Flow ◽  
Gas Turbine Combustor ◽  
Cooling Pattern ◽  
Cooling Hole ◽  
Cooling Enhancement ◽  
Combustor Liner ◽  
Effusion Hole ◽  
Overall Effectiveness

The complex flow field in a gas turbine combustor makes cooling the liner walls a challenge. In particular, this paper is primarily focused on the region surrounding the dilution holes, which is especially challenging to cool due to the interaction between the effusion cooling jets and high-momentum dilution jets. This study presents overall effectiveness measurements for three different cooling hole patterns of a double-walled combustor liner. Only effusion hole patterns near the dilution holes were varied, which included: no effusion cooling; effusion holes pointed radially outward from the dilution hole; and effusion holes pointed radially inward toward the dilution hole. The double-walled liner contained both impingement and effusion plates as well as a row of dilution jets. Infrared thermography was used to measure the surface temperature of the combustor liners at multiple dilution jet momentum flux ratios and approaching freestream turbulence intensities of 0.5% and 13%. Results showed that the outward and inward geometries were able to more effectively cool the region surrounding the dilution hole compared to the closed case. A significant amount of the cooling enhancement in the outward and inward cases came from in-hole convection. Downstream of the dilution hole, the interactions between the inward effusion holes and the dilution jet led to lower levels of effectiveness compared to the other two geometries. High freestream turbulence caused a small decrease in overall effectiveness over the entire liner and was most impactful in the first three rows of effusion holes.

CFD Modeling of a Gas Turbine Combustor From Compressor Exit to Turbine Inlet

1999 ◽  
Vol 121 (1) ◽  
pp. 89-95 ◽  
Author(s):  
D. S. Crocker ◽  
D. Nickolaus ◽  
C. E. Smith
Keyword(s):  
Gas Turbine ◽  
Coupled Model ◽  
Design Tool ◽  
Cfd Modeling ◽  
Gas Turbine Combustor ◽  
Strongly Coupled ◽  
Gas Radiation ◽  
Cfd Models ◽  
Turbine Inlet ◽  
Combustor Liner

Gas turbine combustor CFD modeling has become an important combustor design tool in the past few years, but CFD models are generally limited to the flow field inside the combustor liner or the diffuser/combustor annulus region. Although strongly coupled in reality, the two regions have rarely been coupled in CFD modeling. A CFD calculation for a full model combustor from compressor diffuser exit to turbine inlet is described. The coupled model accomplishes the following two main objectives: (1) implicit description of flow splits and flow conditions for openings into the combustor liner, and (2) prediction of liner wall temperatures. Conjugate heat transfer with nonluminous gas radiation (appropriate for lean, low emission combustors) is utilized to predict wall temperatures compared to the conventional approach of predicting only near wall gas temperatures. Remaining difficult issues such as generating the grid, modeling Swirled vane passages, and modeling effusion cooling are also discussed.

CHARACTERISATIONS OF CHROMIUM CARBIDE-BASED COATED COMBUSTOR LINER FOR GAS TURBINES

2015 ◽  
Vol 76 (10) ◽  
Author(s):  
Salmi Mohd Yunus ◽  
Mariyam Jameelah Ghazali ◽  
Wan Fathul Hakim W. Zamrib ◽  
Ahmad Afiq Pauzi ◽  
Shuib Husin
Keyword(s):  
Gas Turbine ◽  
Chromium Carbide ◽  
Gas Turbines ◽  
Normal Operation ◽  
Gas Turbine Combustor ◽  
Turbine Engine ◽  
Surface Damages ◽  
Wear Damage ◽  
Combustor Liner ◽  
Coating Hardness

A gas turbine combustor liner experienced visible surface damages during its normal operation of 8000 hours. Small amplitudes of vibration during the operation contributed to a surface degradation, mainly wear. A chromium-carbide based hard coating was deposited via plasma spray technique on the outer surface of a combustor liner of a gas turbine engine. It was found that after the operation, the coating hardness had increased more than 30% compared to its minimum initial hardness and reached up to 744 HV particularly in the crossfire tube collar mating areas. Comparison between the coated and the uncoated liners were carried out in order to show how much the wear scars have been minimized throughout the operation under severe temperature of approximately 1, 500°C. It was found that in this study the coating of chromium-carbide is capable to reduce the wear damage due to the work hardening effect of the liner and their mating surfaces.  

Effects of Effusion Cooling Pattern Near the Dilution Hole for a Double-Walled Combustor Liner: Part 1 — Overall Effectiveness Measurements

2018 ◽  
Author(s):  
Adam C. Shrager ◽  
Karen A. Thole ◽  
Dominic Mongillo
Keyword(s):  
Momentum Flux ◽  
High Momentum ◽  
Freestream Turbulence ◽  
Gas Turbine Combustor ◽  
Cooling Pattern ◽  
Cooling Hole ◽  
Cooling Enhancement ◽  
Combustor Liner ◽  
Effusion Hole ◽  
Overall Effectiveness

The complex flowfield in a gas turbine combustor makes cooling the liner walls a challenge. In particular, this paper is primarily focused on the region surrounding the dilution holes, which is especially challenging to cool due to the interaction between the effusion cooling jets and high-momentum dilution jets. This study presents overall effectiveness measurements for three different cooling hole patterns of a double-walled combustor liner. Only effusion hole patterns near the dilution holes were varied, which included: no effusion cooling; effusion holes pointed radially outward from the dilution hole; and effusion holes pointed radially inward toward the dilution hole. The double-walled liner contained both impingement and effusion plates as well as a row of dilution jets. Infrared thermography was used to measure the surface temperature of the combustor liners at multiple dilution jet momentum flux ratios and approaching freestream turbulence intensities of 0.5% and 13%. Results showed the outward and inward geometries were able to more effectively cool the region surrounding the dilution hole compared to the closed case. A significant amount of the cooling enhancement in the outward and inward cases came from in-hole convection. Downstream of the dilution hole, the interactions between the inward effusion holes and the dilution jet led to lower levels of effectiveness compared to the other two geometries. High freestream turbulence caused a small decrease in overall effectiveness over the entire liner and was most impactful in the first three rows of effusion holes.

Sign in / Sign up

Export Citation Format

Share Document