Session: 13-02 - Additive Manufacturing

Paper Number: 122792

122792 - Scaling Heat Transfer and Pressure Losses of Novel Additively Manufactured Rib Designs 

Rib turbulators are a key cooling feature that enable increased heat transfer on the interior of gas turbine components. As metal additive manufacturing becomes available for developing turbine parts, it is becoming increasingly important to understand how the surface roughness intrinsic to this manufacturing method impacts the performance of rib turbulators. To explore the impact roughness has on rib turbulator performance, several relevant scale test coupons were manufactured from a variety of super alloys on a range of additive machines. Additionally, several coupons were built at large scales to effectively reduce the relative roughness size and determine scale effects. A range of different wavy broken rib designs, varying both rib wavelength and orientation within a channel were evaluated. Coupon geometry and surface roughness were characterized using both computed tomography scans and optical profilometry. Variations between the print methods were found to have limited impact on the surface roughness, but significant impact on the accuracy to design intent with rib heights varying by 30%. Following characterization, coupons were flow tested and it was found that the ribs that more regularly disturbed the flow as a function of their geometry most significantly enhanced heat transfer and pressure drop. The performance of the wavy ribs was comparable to other advanced rib designs, such as broken or V shaped ribs.

Presenting Author: Thomas Corbett The Pennsylvania State University

Presenting Author Biography: Thomas Corbett is a Ph.D. candidate at The Pennsylvania State University, conducting research as a member of the Steady Thermal Aero Research Turbine (START) laboratory. Mr. Corbett received a bachelors with honors in Mechanical Engineering from Northern Illinois University, where he worked with the Advanced Research of Materials and Manufacturing (ARMM) laboratory studying the Direct Energy Deposition (DED) and Selective Laser Sintering (SLS) additive manufacturing processes. His current research is focused on developing and understanding additively manufactured internal cooling concepts for use in industrial gas turbines. Mr. Corbett was a recipient of the 2020 University Turbine System Research (UTSR) Gas Turbine Industrial Fellowship (GTIF), which gave him the opportunity to apply his research to commercial engines through a research appointment at Solar Turbines Inc.

Authors:

Thomas Corbett The Pennsylvania State University
Karen Thole The Pennsylvania State University