Research On Design Technology Of Compact And Efficient Centrifugal Compressor Diffuser

The consecutive passage diffuser is a new type of vaned diffuser.Its blade is integrated from the radial inlet to the axial outlet.So when the air flow through the diffuser, it is equivalent to flow through a series of pipes.The channel area distribution form and the channel structural angle distribution form has a decisive influence on the diffuser performance.And the radial size of the diffuser limit the length of the diffuser channel. It also has the important influence on the performance of the diffuser, and the radial size of the diffuser is often decided the radial size of the engine,restricting the development of the engine becoming structural compact.In order to design more compact diffuser with better performance, this article researches three key parameters of the consecutive passage(radius ratio, the channel area and structural angle), mainly includes the following contents:1.Research situation of different radius channel area distribution on the performance of diffuser independent influence lawRespectively in the diffuser largest-import radius ratio were 1.2, 1.4 and 1.6,under the three dimensions of individual study,the design of the diffuser passage area distribution rule.The study found that when the radius ratio of 1.2, the best distribution of channel area is linearity of 0form;Radius ratio of 1.4, the best distribution of channel area is linearity of 12.7;Radius ratio of 1.6,the best distribution of channel area is linearity of 19.6.2. Research situation of different radius of angular distribution channel structure on the performance of diffuser independent influence lawRespectively in the diffuser largest-import radius ratio 1.2, 1.4 and 1.6,under the three dimensions,all plan with the same channel area distribution and separate studies the design of the diffuser channel structure Angle distribution rule.Research shows that, within the scope of the research of this paper, three kinds of radial dimensions, the performance of the diffuser is the channel structure took the maximum angular distribution of linearity, achieve the highest performance.3. Analyzed the effect of the meridional channel structure and blade edge shape of the inlet and outlet on the channel area distributionMeridional channel and edge shape of the inlet and outlet the change of diffuser area distribution form has a certain impact, but most among channel area distribution curve shape remains unchanged,linearity of the values and the channel area distribution curve body shape was not affected.Study shows that the meridional channel and blade edge shape of the inlet and outlet the change does not affect the diffuser passage area distribution law.The channel main body shape of the area distribution curve determines the diffuser performance of high and low.4. Analyzed the coupling effect of Radius ratio, the channel area distribution and tectonic angular distribution on the performance of diffuserThrough the radius ratio, channel area and channel Angle of the three channel structure preserved form of a single cross analysis and comparison of the influence of the diffuser performance,within the scope of the research of this paper, diffuser channel area distribution and channel structure Angle distribution of independence, the area of distribution on the diffuser performance influence is bigger, especially took the best channel area distribution, channel structure Angle distribution over awide range of little impact on the diffuser performance.Diffuser radius ratio on the best channel area distribution of law is more apparent, as the diffuser radius is bigger, the best channel area distribution of linearity increase gradually.5. Modify a sectional vaned diffuser to conformal retrofit designAccording to law in this paper, we study the design of a certain sectional diffuser highest performance point as design point, two kinds of conformal leading design improvements, one is to keep meridional channel consistent retrofit design and prototype, another kind is to reduce the size of the radial retrofit design, in order to verify the accuracy of the law in this paper, we study the design.Studies show that the two conformal leading design scheme can obtain a prototype of higher performance, suggesting that conformal single diffuser structure is segmented blades expansion pressure apparatus has the advantage of compactness and high performance.