Faculty Advisor

Sisson, Richard D.


Using Unigraphics, a computer model incorporating a leading edge shadow bar has been developed to predict EB-PVD coating thickness for a PW4000 second stage blade. The effects of shadow bars were studied, and interesting results were discovered. The results of the computer model experiments indicated that the addition of a leading edge shadow bar effects the concave surface of the blade the most while it has minimal effects on the coating thickness on the convex surface. When increasing the diameter and/or distance of the shadow bar from the leading edge, the amount of TBC deposition on the concave surface of the blade will decrease. It was concluded that a leading edge shadow bar should not be utilized in the coating process as it reduces the amount of TBC distributed to the concave side, which is a section of the turbine blade that typically requires more coating, not less. Normalized comparisons between the prediction model and actual data were made, and the graphs showed that the sets of data followed a similar trend line, which ultimately means the modified prediction model does in fact work.


Worcester Polytechnic Institute

Date Accepted

January 2002


Mechanical Engineering

Project Type

Major Qualifying Project


Restricted-WPI community only

Advisor Department

Mechanical Engineering