The Aerodynamic Optimization Design Of Medical Micro-Turbine

The non-invasive ventilator is widely applied in the filed of first-aid, treatment, etc. The high-performance ventilators applied in the domestic market are mainly imported from abroad which are quite expensive. Thus there is a large demand of products researched and produced independently in China to fill the domestic void. The key component of the non-invasive ventilator is the micro-turbine. It is a convenient and reliable method to conduct aerodynamic analysis and optimization on the turbomachinery by numerical simulation. However, there are little research about aerodynamic analysis and optimization of medical micro-turbine and few reference can be referred to in our country. On basis of this, this study chose the plastic micro-turbine as the subject and conduct the following research:(1) Aerodynamic design of medical micro-turbine. With the performance parameter, the theoretical design was computed in order to acquire the geometric dimensions of the medical micro-turbine. The three-dimensional model of the micro-turbine was built up by the software CFTurbo, and prepared for further aerodynamic analysis. (2) Analysis on the flow field of medical micro-turbine. The grid of the flow passage was divided and the aerodynamic performance was analyzed with the Fine/Turbo module of NUMECA software. As a result, the efficiency was81.53%and the performance curve procured through calculation on the other7working condition points. Analyse the pressure and relative velocity distribution at the design point, the low pressure (or large flow)point and the high pressure (or small flow) point, and the results showed that the pressure and relative velocity distribution of the flow field were not ideal. Thus further aerodynamic optimization is necessary.(3) Aerodynamic optimization of the medical micro-turbine. The parametric module and aerodynamic optimization were built by the Fine/Design3D module of NUMECA software. The efficiency of micro-turbine was raised to approximately3.2%after optimization, and the range of the performance curve was expanded. Comparatively analysed the pressure and relative velocity distribution at the same working condition points before and after optimizating the micro-turbine, whose aerodynamic performance was improved after optimization, especially at the design point and the low pressure(or large flow)point.(4) Calculate the strength and analyse the torsional vibration of the medical micro-turbine. I used the Hypermesh software to divide the grid of the fine element; the ABAQUS software to calculate the static strength and dynamic strength; the ARMD software to analyse the torsional vibration of the micro-turbine after optimization. The results from calculation and analysis demonstrated that the mini-turbine can meet the requirements of the strength and torsional vibration after optimization, thus it safe and reliable. At last, the micro-turbine after optimization was producted.