Design and performance analysis of ORC centrifugal pumps

Abstract

The purpose of this work is to design and determine the performance of a prototype centrifugal pump impeller for an organic Rankine cycle (ORC) power plant of maximum power 100 kW. The centrifugal pump is especially designed to work on the same shaft as the corresponding ORC microturbine. The ORC unit works on R7100 (HFE7100) - a low-boiling fluid characterized by a zero ozone depletion potential coefficient. The pump has the following rated parameters: nominal flow rate of working fluid 4 kg/s, operating rotor speed 10 000 rpm. The pump designed by means of the 0D meanline method is subject to computational fluid dynamics (CFD) calculations and analysis. The obtained flow field results are discussed and performance characteristics of the pump are presented. The non-cavitating operational region is determined for the pump.