Experimental And Simulation Study On Key Components Of Small-Scale ORC System

In the field of low temperature industrial waste heat recovery,solar thermal power generation,biomass power generation,geothermal power generation and other fields,small-scale organic Rankine cycle is a viable and technically promising technology.In the process of miniaturization of ORC system,there are some technical difficulties,such as the selection of suitable small expander,small size and can meet the needs of the ORC system heat exchanger.In order to study the performance of the small screw expander and dry bushing heat exchanger in ORC system,a detailed experimental model of ORC system is established in this paper.The results show that the feasibility of using a screw expander in a small ORC system can achieve greater expansion ratio and have greater potential for optimization.The dry bushing heat exchanger has a compact shape and a long stroke and can realize circulating medium in the ORC system The large temperature rise required meets the needs of the ORC evaporator and condenser.Due to the use of the screw expander and the dry tube heat exchanger that allow the liquid to participate in the expansion,under the constant heat source,the performance of the ORC system has been found to be significantly changed with the performance of the working fluid pump by both controlling the circulating flow through the working fluid pump Adjust the media at the evaporator outlet to allow the ORC cycle to operate at its optimum.In this paper,for a 100? heat source and a 15? cold source,the designed small-scale ORC unit has a maximum power generation of 1.5 kW and a thermal efficiency of 4.6%.This article also based on the Python language to establish a detailed ORC cycle calculation model,the model considered in the expander cycle medium mixed oil situation,so that it is closer to the actual operation.The experimental data show that the simulation deviation of the isentropic efficiency of the expander is not more than 10.2% and the simulation error of the unit circulation efficiency is not more than 16.80%.