The model pump with rectangular volute, cylindri-cal blade and half open impeller was developed based on the GY65-200 molten salt pump. Under the design condition,the flow rate Q,head H and rotational speed n d equal 25 m 3 /h,32 m, 1450 r/min, respectively. In order to measure full flow fields in the pump conveniently, suction pipe and volute were made of plexiglas, and the other parts were made of stainless steel.

    Considering the applicability of PIV measurement and process-ability of plexiglas, some structures of the model pump were simplified based on the original molten salt pump. For example, the bending radius from the suction chamber to impeller was smaller than that of original pump, and the section of the volute was rectangle whose hydraulic performance was worse than trape-zoid. Therefore, the hydraulic performance of the model pump was not as good as the original pump, but it can meet the requirement of the research in this paper. Based on the improvement of the structure, the flow fields in most of impeller and volute and whole of suction chamber can be measured by using PIV. The structure of the model pump is more reasonable than that in references.