A design method of volute profile under the restriction of fixed shape and size

Abstract

The invention discloses a method for designing the profile of a volute under the limitation of fixed dimensions. Specifically, the profile of the volute is limited in size, and the XY rectangular coordinates of the profile are converted into angle-distance coordinates; the maximum size value is determined; Set 7 control points; calculate the node vector based on the non-uniform B-spline curve, establish the basis function, and get the points on the volute shape line in the form of angle-distance from the basis function and 7 control points; draw the volute shape Line; Numerical simulation is performed on the q group of sample points corresponding to different optimization variables to obtain the aerodynamic performance of the fan; finally, an approximate model is established to solve the best Pareto solution. The present invention improves the structure of the volute by performing non-uniform B-spline curve fitting on the structure of the volute profile, especially the distance from a point on the volute profile to the center of the impeller, and locally adjusts it by adjusting the coordinates of the control points The profile of the volute can be partially adjusted to meet engineering requirements and improve performance.

Description

technical field [0001] The invention belongs to the field of centrifugal fans, and more specifically relates to a method for designing a volute profile under the limitation of a fixed shape and size, which is suitable for the volute profile of a centrifugal fan, and the volute is especially a multi-wing centrifugal fan volute with size limitations. Shell, especially suitable for range hoods. Background technique [0002] In household appliances, due to the limitation of size and space, especially in the design of range hoods, the size is developing toward smaller size, so that the volute of the multi-blade centrifugal fan is cut to meet the requirements of the small internal space of the range hood. At present, the volutes on the market are all cut in a straight line, and the cross-sectional area of ​​the volute undergoes a mutation process of first becoming smaller and then larger, so that the gas flowing out of the impeller flows and separates seriously at this cutting pos...

AI Technical Summary

Problems solved by technology

In the design of multi-blade centrifugal fan with the above design method, the designed volute size is often too large, which does not meet the size requirements of the space.

In engineering applications, the design requirements are achieved by adjusting the local profile of the volute, but the direction and size of the adjustment must be determined according to actual experience, which is often time-consuming and laborious, and the profile of each section of the volute must be satisfied during the adjustment process The smoothness between them increases the difficulty of the volute profile design

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