Static And Modal Analysis Of Compressor Blade Based On The Fluid-structure Interaction

The improvement of aero engine technology has promoted the developing of high load and high rotation speed compressor greatly. One hand, the compressor blades rotating with the high rotation speed in practice not only bear the large centrifugal load, but also tremendous pneumatic load foamed by the pressure differences between both sides of blade,under the interaction of two kinds of load, the blades will yield in different degrees of deformation. The other hand, the compressor blades will be subjected to various mechanical vibration in the practical working, and the damage triggered by mechanical vibration is caused by resonance. When the frequency of external excitation force is approaching to the natural frequency of blade, the amplitude of blade will increase sharply, which may cause a blade fatigue or even break. In view of these problems,this paper did a research on the compressor aerodynamic characteristics of blade、static deformation and modal respectively based on the ANSYS Workbench platform with NASA Stage35 test compressor as the research object, the related research content mainly involved the followings:1. Establish compressor fluid domain and structure domain. First modeling the preliminary three-dimensional compressor blade by UG, drawing the meridional channel by BladeEditor, then refactoring the blade by BladeGen, next we imported it into the TurboGrid and DesignModeler to establish compressor fluid domain and structure domain, which laid a foundation for aerodynamic performance analysis of compressor、static and modal analysis of compressor blade based on the fluid-structure interaction.2. Aerodynamic performance analysis of compressor. In order to improve the computational efficiency we adopted Workbench as the calculation control platform. Through CFX solving the fluid domain and then obtained compressor pressure ratio, temperature ratio,flow rate and efficiency characteristic parameters. In order to verify the accuracy of numerical simulation, we compared above parameters with the test results and analyzed the internal flow field、blade surface pressure distribution、errors and so on in detail.3. Static analysis of compressor blade based on the fluid-structure interaction. We not only analyzed the maximum deformation quantity and the maximum equivalent stress of stainless steel、titanium alloy and aluminum alloy rotor blade quantitatively, but also analyzed the pneumatic deformation、rotational deformation and combine deformation corresponding to deformation quantity distribution and equivalent stress. After that doing a research on the variation of different material rotor blade tip clearance under the 100% working condition with the outlet pressure changing, we analyzed the stator blade deformation under 100%working condition with the outlet pressure changing.4. Modal analysis of compressor blade based on the fluid-structure interaction. Through modal calculation the natural frequencies and modal vibration mode of each order of stainless steel、titanium alloy and aluminum alloy rotor blade under non-prestress、pneumatic-prestress and rotational-prestress of different rotation speeds were obtained. Finally we drew the Campbell by the nature frequency of rotor blade of different rotation speeds and excitation force and then analyzed the resonance of the rotor blade based on the Campbell.