Date of Award
2024
Document Type
Thesis
Degree Name
Master of Science in Engineering (MSE)
Department
Mechanical and Aerospace Engineering
Committee Chair
Phillip Ligrani
Committee Member
Haiyang Hu
Committee Member
Hallie Collopy
Research Advisor
Phillip Ligrani
Subject(s)
Turbines--Blades--Aerodynamics, Surface roughness, Additive manufacturing
Abstract
Additive manufacturing (AM) allows the production of high strength and high temperature alloys to increase the operational temperature of turbines and other engine components. AM inherently has high surface texturing, inclusive of waviness due to the layering effect in the laser powder bed fusion (L-PBF) process, and roughness due to surface defects such as partially sintered powder, deep notches, and micro-cracks. This thesis investigates how different surface treatments affect the surface static pressure variations and wake aerodynamic loss characteristics for each blade. A supersonic transonic blow down wind tunnel with a linear cascade test section is used to acquire this experimental data. Each blade is instrumented with 22 pressure taps along the 50% to measure surface static pressure, while a motorized traverse sweeps a pitot static pressure probe through the wake 0.25Cx downstream of the cascade. Downstream wake aerodynamic profiles for the blades with lower magnitudes of surface roughness evidence larger magnitudes of loss parameters, which are spread over larger areas, compared to distributions associated with higher roughness configurations. Blade wakes associated with higher Ra and ks/Cx values are also generally asymmetric and additionally experience a lower decrease in local Mach number throughout the wake.
Recommended Citation
Herrin, Chase Allen, "Aerodynamic losses of additively manufactured blades in transonic conditions with different surface treatments" (2024). Theses. 705.
https://louis.uah.edu/uah-theses/705