The impeller of the 100-YQH multistage axial flow pump, which is part of the flow field calculation. When modeling the impeller, it is based on the wooden model of the impeller, and the wooden model is given by using a plurality of imaginary cylindrical surfaces concentric with the impeller but different radii to cut the plane of the blade; therefore, When modeling, you need to restore these planar unfolded images to these concentric cylinders. In this case, you must first perform coordinate transformation to transform the known plane coordinates into cylindrical coordinates. When the coordinates are transformed, according to the known cylindrical surface radius. The coordinates are calculated using the relationship of the chord length equal to the arc length, and the z coordinate remains unchanged. Point generation: First, generate concentric cylindrical faces of different radii, then input the coordinates of the upper points of the airfoil obtained by the coordinate transformation, and generate points on the cylindrical surface; the types of these points must be virtual (ie, Virtual type), cannot be Real point (ie Real type). Because in the future transformation, some commands are inoperable to the real point; if you want to convert the virtual point to a real point in the future, Gambit has commands to implement this function, but there is no opposite operation command. Line segment generation: Select the generation method and type of the line, select to generate the Real type NUBS curve, and then connect the points into a line. Note: Although the points at this time are on the cylindrical surface, these lines are not necessarily on the cylindrical surface. Surface generation: First, check if the line segments are connected together to form a closed surface. If the line segment is not closed, select the link command to close the line segment; in this case, you may find some extra line segments, but you can't delete them directly (possibly because other entities are referring to them), then you need to go back to the connection point command and pass Connect the 2 endpoints of the line segment and delete the line segment. After checking the tightness of the line segments, you can use these line segments to generate faces; however, these line segments are not on the cylindrical surface, so you need to select a mother face (that is, a host, select the corresponding cylindrical surface) for the generated face. Given tolerances, Gambit automatically generates faces that are less than the tolerance of the parent side on the parent side. According to the above steps, after generating the virtual surfaces of different cylindrical faces, the virtual surfaces are deleted, but the line segments constituting the faces are reserved, and the line segments are located on the cylindrical surface and are connected to each other. The lines are then created using these segments, which are the outer surfaces of the blade. (Finish)