Study on micro-pit structure on blade surface of high flow margin centrifugal compressor

Abstract

The stability of compressor operation has an inducing and amplifying effect on the stability and performance of the entire engine. Therefore, it is required that the flow margin of the compressor should be wider to adapt to the working stability of the engine under variable operating conditions. A new blade structure with micro pits distributed on the suction surface of the mainstream blade is proposed based on "Golf ball effect". The flow of a certain type of centrifugal compressor impeller is numerically simulated by using the CFX fluid dynamics software to study the effect of adding micro pits on the performance of flow separation structure and flow margin at different parts of the suction surface of the blade. Study the effect of adding micro pit structures with radii of 0.25~0.30 mm at different parts of the blade suction surface on structural performance and flow margin. The results show that adding micro pits at the leading and trailing edges of the mainstream blade suction surface can improve the flow margin. When the radius of the micro pits is 0.3 mm, the flow margin effect is the best, which are increased by 3.01% and 3.15% respectively. The use of new structural blades can increase the compressor flow margin, and provide a reference for the design of centrifugal compressor impellers.

Keywords

• centrifugal compressor
• golf ball effect
• micro structure
• flow margin