In a high thrust-weight-ratio aero-engine,turbine blades are exposed to extremely high temperature and pressure which sets higher demands in the blade cooling technology.To boost film-cooling effectiveness,an accurate...In a high thrust-weight-ratio aero-engine,turbine blades are exposed to extremely high temperature and pressure which sets higher demands in the blade cooling technology.To boost film-cooling effectiveness,an accurate,efficient,and all-sided inspection of film cooling holes is urgently requested to ensure the quality of turbine blades.The tiny size of film-cooling holes adds to extreme difficulties in the inspection process both by contact and non-contact measurement.This paper proposed a non-contact measuring technique to cope with the inspection of turbine blades.A specially designed light-field camera with a small field of view and proper depth of field is applied to resolve a 3D geometry of film cooling holes.The technique uses one light field camera to capture images of the blade surface.3D lightfield reconstruction algoritm is applied and point cloud of the blade is generated.Due to the compactness of the non-contact single light-field imaging system,information inside the holes becomes attainable.By precisely controlling the relative pose of the camera to the blade surface,the device can obtain hole diamter and outlet angle with an accuracy of±0.03mm and±1°17’respectively.The average time consumed for reconstructing one film cooling hole is about 5 seconds.展开更多
基金Aero Engine Corporation of China(HFZL2020CXY014-1,HFZL2020CXY014-2)。
文摘In a high thrust-weight-ratio aero-engine,turbine blades are exposed to extremely high temperature and pressure which sets higher demands in the blade cooling technology.To boost film-cooling effectiveness,an accurate,efficient,and all-sided inspection of film cooling holes is urgently requested to ensure the quality of turbine blades.The tiny size of film-cooling holes adds to extreme difficulties in the inspection process both by contact and non-contact measurement.This paper proposed a non-contact measuring technique to cope with the inspection of turbine blades.A specially designed light-field camera with a small field of view and proper depth of field is applied to resolve a 3D geometry of film cooling holes.The technique uses one light field camera to capture images of the blade surface.3D lightfield reconstruction algoritm is applied and point cloud of the blade is generated.Due to the compactness of the non-contact single light-field imaging system,information inside the holes becomes attainable.By precisely controlling the relative pose of the camera to the blade surface,the device can obtain hole diamter and outlet angle with an accuracy of±0.03mm and±1°17’respectively.The average time consumed for reconstructing one film cooling hole is about 5 seconds.