The Research Of Aerodynamic Secondary Structure Of Turbine

Turbine design totally include aerodynamic and structural design. It’s an important direction for the research of turbomachinary. A good design system has the vital role and the significance for the promote of development of high performance aero engine.Computational fluid dynamics developed made turbine design system rapidly developed. It’s still a challenging research topic. In this thesis, based on conventional turbine design system the modified design system has been studied. To improve the 1.5 stage turbine’s efficiency,blade bow and sweep in the modified design system has been adoped, to retrofit the prototype blade and made the aerodynamic analysis and research. Firstly, based on conventional turbine design system, studied the accessory structure in cascade passage, such as pin fin, fence and fiction damper, or something else for blade machining such as slot, blade bow and sweep or endwall profiling. Based on different categories to make a summary of research for their development process and direction of the research with their conclusions. Built a secondarygeometric structure design system different from the first geometric structure in the procedure of conventional turbine design system.To reduce the loss and improve the efficiency, The main part of the secondary geometric structure design system can be adopt to retrofit the selected 1.5 stage turbine blade for different three modes conclude different bending angle for positive bending, reverse bending and J form bending with the same bending height. Make a systematic analysis by using the method of numerical simulation. Numerical results showed that static blade retrofit for J form bending and small angled positive bending have a great effect for efficiency improvement,they made the secondary flow loss decreased in different degrees, turbine aerodynamic performance is improved. But static blade retrofit for reverse bending and large angled positive bending made the flow field worsen. It’s also demonstrated that the combination of conventional turbine design system and the secondary geometric structure design system represented by advanced technology about blade bending, can make the vortex and flow in cascade be reasonable controlled, make boundary layer flow more favorable and secondary flow loss decrease. Combined with the other secondary geometric structure for blade cooling,friction and strength, make it be a turbine design system with higher performance.