A Numerical Analysis of 3d Flow in a Transonic Turbine Cascade Facility for Aerodynamic Loss Minimization

Open Access
Author:
Herwig, Nicholas Lee
Graduate Program:
Aerospace Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
August 01, 2013
Committee Members:
  • Cengiz Camci, Thesis Advisor
Keywords:
  • turbine cascade facility
  • wind-tunnel
  • stagnation chamber
  • linear cascacde
Abstract:
The ability to test engineering ideas and designs at a computational level – before conducting physical tests and even far before real world operation – is a vital and necessary step in the development of that idea and design. Through the use of Computational Fluid Dynamics (CFD) we are able to test and improve numerous designs prior to conducting a physical test. This ability allows for the best possible model to be designed for continuation into a physical model and to validate the CFD analysis. Discussed here is the applied computational fluid dynamics study and design optimization of a current High Speed Turbine Cascade Facility already existing in the department of Aerospace Engineering. The current facility, located in the Hammond Building of the Pennsylvania State University Campus, and its three-dimensional flow characteristics were modeled with and without a linear cascade test-section attached. Initial designs were analyzed without the cascade in order to decrease computational time and increase the number of designs analyzed of the delivery ducting to the cascade. Designs were focused in two regions of the facility; the initial diffuser out of the second elbow and the stagnation chamber prior to the intended test-section region. Within this diffuser a splitter plate was installed as a preventative separation device for the flow entering the stagnation chamber. However, the splitter plate proved to choke and diminish the energy of the flow and was thus not further analyzed with the addition of the linear cascade system. The modified model, which was designed with a rectangular cross-section, and not a circular, stagnation chamber, proved to reduce total pressure losses measurably. A six-bladed/seven-passage linear cascade system was computationally designed and evaluated with both the existing facility design and the modified design.