Steam flow is the main form for energy transfer in power plants, process industries, etc. The flow rate of the steam relates to the energy transfer amount directly. Pressure reducing valves are used for flow rate control of the compressible superheated steam in these piping systems. In this paper, a pressure reducing valve with a novel valve core is proposed. In order to analyze the internal flow characteristics of the compressible superheated steam and the flow rate adjustment performance of the proposed pressure reducing valve, a numerical model of DN80 pressure reducing valve is established. Then, the flow characteristics inside are studied numerically. Meanwhile, the flow rate adjustment performance is also carried out experimentally. Compared with the numerical and experimental results, it shows an agreement and both of them are similar to linear flow rate. Furthermore, a fitting equation for the flow rate prediction is carried out for the engineering applications under different working conditions. (C) 2017 Elsevier Ltd. All rights reserved.