Brief Biography：

Dr. Young-Seok Choi was graduated at the Department of Mechanical Engineering, Seoul National University, Korea, and got the Bachelor, Master and PHD degree in 1988, 1990 and 1996. His research interests include product development of turbo machinery, numerical simulations, experiment techniques, etc.

Abstract：

In this study, series of optimized design for centrifugal type pump and mixed-flow pump having a specified specific speed were developed using computational-fluid-dynamics (CFD).  The various kind of design parameters and performance characteristics were studied with regard to the specific speed in order to create a hydrodynamic design system for pumps.   A centrifugal pump consists of an impeller and a volute and mixed-flow pump consists of an impeller and a diffuser. The shapes vary with certain tendencies depending on the specific speed.  Once the tendencies of the shapes are understood it becomes possible to easily design optimum shapes for any given specific speed. Design variables of the impeller, volute and diffuser were defined in order to design a centrifugal pump and a mixed-flow pump optimally at certain specific speed. Optimum design was carried out on the defined design variables using design-of-experiment(DOE). Using an optimally designed shape of pumps at certain specific speed, the characteristic and the tendencies of design variables were analyzed depending on the specific speed. Two important performances such as efficiency and suction performance are considered as objective functions.  The numerical results for the optimization were validated by comparing them with experimental data for the total head, efficiency and NPSHr. These kind of design systems are verified with experiments at several different specific speeds.