Sand Ingestion Equipment Design And Test Of A Whole Helicopter Auxiliary Power Unit

Sand ingestion of an aircraft engine can damage the internal passage of the engine,cause performance deterioration,reduce life of attenuation,and affect flight safety.Exploring the change rule of structure and properties after the aircraft engine ingesting sand is important for engine design.The design of the sand ingestion equipment is based on the sand ingestion test of an auxiliary power unit.The sand flow adjustment depends on theoretical analysis and equivalent design concept.The verification of the concentration uniformity and the analysis of sand trajectory is used by CFD.The characteristics of sand ingestion equipment is obtained from debugging data.The trend of the performance of the auxiliary power unit is also analyzed.Sand ingestion test of aircraft engine is indispensable for the engine development.The test of sand ingestion has not been carried out in China.So the design of the sand ingestion equipment for auxiliary power unit is essential.The conclusions of the sand ingestion test of auxiliary power unit is as following:1)The design of the sand ingestion equipment is reasonable,the sand rate of flow can be adjustable,and the sand concentration is well-proportioned.2)The function of the sand ingestion equipment is satisfied to the test regulations.3)The airflow outlet is decreased,the compressor outlet is increased,the exhaust gas tempereture is raised,the shaft power is reduced,the fuel flow is lessened.The performance of the auxiliary power unit is attenuated gradually during the test period.4)The internal passage is abraded obviously after the sand ingestion test.