Experimental Analysis of Partial Evaporation Micro-ORC for low-temperature Heat Recovery

Abstract In this paper, we present an experimental assessment of the performance a partial evaporating organic Rankine cycle (PE-ORC) power system. The system converts low temperature heat into electrical energy, with size around 1 kW, thus suitable for micro-generation in residential sector. Although test bench was designed operating superheated vapour at expander inlet, it has demonstrated to be able work expansion occurring entirely two-phase condition. Since direct measurement quality is not possible using sensors installed rig, state fluid condition estimated by means thermal balance exchangers, so thermodynamic can evaluated. Temperatures source range between 40 °C and 75 have been tested, each value inlet varied regulating feed-pump rotating speed. Experimental data are provided regarding overall cycle, feed-pump. It observed that effectiveness evaporator efficiency pump improved respect operation inlet. However, lower, especially due high ratio consumption over produced power, commonly called back (BWR). latter, under some boundary conditions, resulted higher than unit, meaning produce net power. aim paper identify design characteristics required micro-ORC energy order enhance its PE mode.