A Multistage centrifugal pump design process for cryogenic fluids

Cryogenic pumps circulate and pressurize liquefied gases in various industrial applications, such as liquefied natural gas (LNG) transfer from storage tanks, refrigeration systems, and Organic Rankine Cycle (ORC) systems. Using an unsuitable industrial pump as the cryogenic pump could lead to cavitation phenomena due to inadequate suction performance and might also negatively affect the overall performance of the system. In refrigeration and ORC systems, the efficiency of the pump is a key parameter, and the selection of a suitable cryogenic pump plays a crucial role in achieving system efficiency and net power output. In this paper, a thirty-stage centrifugal pump is designed for a 3.4 kW ORC power plant using R290 as the working fluid. The hydraulic design of the individual pump components (impeller, radial diffuser, return vanes, and volute casing) is carried out at the planned main operating point of the system, defined in terms of the required mass flow rate and the static pressure rise, by means of 1D calculation procedures based on the available literature. Particular attention is paid to the design of the impeller eye and the blade leading edge (LE) in order to reduce the risk of cavitation problems. After this preliminary design phase, Computational Fluid Dynamics (CFD) simulations are performed to assess the non-cavitation performance of the multistage centrifugal pump previously designed. Copyright © 2025 by ASME.