Sector Rig Test of a Ceramic Matrix Composite (CMC) Combustor Liner

Ceramic Matrix Composite (CMC) combustor liners, due to their high temperature capability, enable the elimination of film cooling present in current metallic liners without increasing the pressure drop in the combustor section of a gas turbine engine. The absence of film cooling and the higher temperature capability of the CMC liner leads to complete combustion of carbon monoxide (CO) close to the combustor walls, resulting in a lower emissions combustor. The benefit of lower CO emissions was predicted through the use of stirred reactor network models in which a series/parallel set of individual perfectly stirred reactors (PSRs) is coupled to simulate a combustor. The paper describes the component design and analysis, emissions modeling, fabrication, and sector rig testing of silicon carbide fiber reinforced silicon carbide matrix (SiC/SiC) combustor liners.

Download Full-text

Ceramic Matrix Composite Turbine Vanes for Gas Turbine Engines

Volume 1: Turbo Expo 2005 ◽

10.1115/gt2005-68229 ◽

2005 ◽

Cited By ~ 7

Author(s):

Venkat Vedula ◽

Jun Shi ◽

David Jarmon ◽

Scott Ochs ◽

Lola Oni ◽

...

Keyword(s):

Silicon Carbide ◽

Gas Turbine ◽

Matrix Composite ◽

Thermal Stresses ◽

Ceramic Matrix Composite ◽

Ceramic Matrix ◽

Component Reliability ◽

Turbine Engine ◽

Component Design ◽

Turbine Vanes

Ceramic matrix composite (CMC) turbine vanes, due to their high temperature capability, allow significantly higher firing temperatures with minimal cooling. Turbine vanes were designed for a gas turbine engine with special attention to attachment methods that minimize thermal stresses due to large differences in coefficients of thermal expansion between the CMC airfoil and metal platforms. Detailed aerodynamic, thermal and structural analyses were performed to ensure component reliability. The paper describes the component design, analysis, fabrication, and rig testing of a silicon carbide fiber reinforced silicon carbide matrix (SiC/SiC) turbine vane.

Download Full-text

Design Considerations for Ceramic Matrix Composite Vanes for High Pressure Turbine Applications

Volume 4: Ceramics; Concentrating Solar Power Plants; Controls, Diagnostics and Instrumentation; Education; Electric Power; Fans and Blowers ◽

10.1115/gt2013-95104 ◽

2013 ◽

Author(s):

Robert J. Boyle ◽

Ankur H. Parikh ◽

Michael C. Halbig ◽

Vinod K. Nagpal

Keyword(s):

High Pressure ◽

Matrix Composite ◽

Film Cooling ◽

Ceramic Matrix Composite ◽

Ceramic Matrix ◽

Temperature Gradients ◽

High Pressure Turbine ◽

Trailing Edge ◽

Temperature Capability ◽

Higher Temperature

Issues associated with replacing conventional metallic vanes with Ceramic Matrix Composite(CMC) vanes in the first stage of the High Pressure Turbine(HPT) are explored. CMC materials have higher temperature capability than conventional HPT vanes, and less vane cooling is required. The benefits of less vane coolant are less NOx production and improved vane efficiency. Comparisons between CMC and metal vanes are made at current rotor inlet temperatures and at an vane inlet pressure of 50 atm.. CMC materials have directionally dependent strength characteristics, and vane designs must accommodate these characteristics. The benefits of reduced NOx and improved cycle efficiency obtainable from using CMC vanes. are quantified Results are given for vane shapes made of a two dimensional CMC weave. Stress components due to thermal and pressure loads are shown for all configurations. The effects on stresses of: (1) a rib connecting vane pressure and suction surfaces; (2) variation in wall thickness; and (3) trailing edge region cooling options are discussed. The approach used to obtain vane temperature distributions is discussed. Film cooling and trailing edge ejection were required to avoid excessive vane material temperature gradients. Stresses due to temperature gradients are sometimes compressive in regions where pressure loads result in high tensile stresses.

Download Full-text

Influence of the braided structure on the film cooling performance over the ceramic matrix composite plate

International Journal of Thermal Sciences ◽

10.1016/j.ijthermalsci.2021.107112 ◽

2021 ◽

Vol 170 ◽

pp. 107112

Author(s):

Zecan Tu ◽

Chenwei Zhao ◽

Junkui Mao ◽

Xiao Zhao ◽

Xingsi Han

Keyword(s):

Matrix Composite ◽

Film Cooling ◽

Composite Plate ◽

Ceramic Matrix Composite ◽

Ceramic Matrix ◽

Cooling Performance ◽

Braided Structure

Download Full-text

Effect of a Ceramic Matrix Composite Surface on Film Cooling

10.1115/gt2021-59602 ◽

2021 ◽

Author(s):

Peter H. Wilkins ◽

Stephen P. Lynch ◽

Karen A. Thole ◽

San Quach ◽

Tyler Vincent ◽

...

Keyword(s):

Heat Transfer ◽

Matrix Composite ◽

Film Cooling ◽

Gas Turbines ◽

Ceramic Matrix Composite ◽

Ceramic Matrix ◽

Composite Surface ◽

Minimal Impact ◽

Cooling Hole ◽

Adiabatic Effectiveness

Abstract Ceramic matrix composite (CMC) parts create the opportunity for increased turbine entry temperatures within gas turbines. To achieve the highest temperatures possible, film cooling will play an important role in allowing turbine entry temperatures to exceed acceptable surface temperatures for CMC components, just as it does for the current generation of gas turbine components. Film cooling over a CMC surface introduces new challenges including roughness features downstream of the cooling holes and changes to the hole exit due to uneven surface topography. To better understand these impacts, this study presents flowfield and adiabatic effectiveness CFD for a 7-7-7 shaped film cooling hole at two CMC weave orientations. The CMC surface selected is a 5 Harness Satin weave pattern that is examined at two different orientations. To understand the ability of steady RANS to predict flow and convective heat transfer over a CMC surface, the weave surface is initially simulated without film and compared to previous experimental results. The simulation of the weave orientation of 0°, with fewer features projecting into the flow, matches fairly well to the experiment, and demonstrates a minimal impact on film cooling leading to only slightly lower adiabatic effectiveness compared to a smooth surface. However, the simulation of the 90° orientation with a large number of protruding features does not match the experimentally observed surface heat transfer. The additional protruding surface produces degraded film cooling performance at low blowing ratios but is less sensitive to blowing ratio, leading to improved relative performance at higher blowing ratios, particularly in regions far downstream of the hole.

Download Full-text