Session: 13-04 Thermal Performance of Coatings, Ceramic Composites, and Additively Manufactured Metal Hardware

Paper Number: 104059

104059 - Design and Cooling Performance of Additively Manufactured Ceramic Turbine Vanes 

Ceramic materials are of significant interest in aviation and power generation applications that use gas turbines, due to their low density and ability to withstand high temperatures. Increased cycle thermal efficiency and higher specific power output is possible by incorporating ceramic components that enable high turbine inlet temperatures and lower required cooling airflow levels. However, ceramics can be difficult and costly to form into the complex shapes used in gas turbine components, often requiring specialized multi-step processes. Furthermore, ceramic components in the hottest areas of a gas turbine, such as vanes or blade shroud seals, will still likely require cooling which is challenging to implement in conventional ceramic manufacturing approaches. In this study, a polymer derived ceramic (PDC) additive manufacturing (AM) process was developed to print an aviation engine-scale gas turbine vane with complex internal cooling configurations. An FEA thermomechanical optimization model was developed to generate an internal cooling design that utilizes pin fins to augment internal heat transfer from the vane surface. This optimized design, along with a baseline internally cooled vane, was tested in a transonic linear cascade which allows for matched engine Mach and Reynolds conditions. Infrared thermography was used to evaluate blade surface temperatures to determine the overall cooling effectiveness for both the baseline ceramic vane and the optimized design. Overall cooling effectiveness for a baseline internally cooled ceramic airfoil is lower compared to metallic airfoils due to lower material thermal conductivity, which necessitates highly efficient internal cooling. Suction side cooling effectiveness values are lower than the pressure side due to large differences in local Mach number. Finally, the optimized internally cooled vane had significantly improved levels of overall cooling effectiveness relative to the baseline due to high surface area and internal convection coefficients.

Presenting Author: Andrew Fox The Pennsylvania State University

Presenting Author Biography: Andrew completed his bachelor's degree in mechanical engineering from the Pennsylvania State University and is currently a graduate research assistant at Penn State's Experimental and Computational Convection Lab (ExCCL), where he's finishing up his master's degree in mechanical engineering. Andrew operates the lab's transonic linear cascade where he's researching the effects of compressibility on true scale, turbine blade cooling performance, as well as the performance of advanced turbine materials.

Authors:

Andrew Fox The Pennsylvania State University
Stephen Lynch The Pennsylvania State University
Jason C. Young Colorado School of Mines
Carl P. Frick Colorado School of Mines
Jennifer Hankins University of Wyoming
Kyle Kuhn University of Wyoming
Stephan A. Brinckmann University of Wyoming
Ray S. Fertig III University of Wyoming