Development and optimization of efficient small-scale turbines for organic rankine cycle powered by low-temperature heat sources

[摘要] In this this research, ORC systems using axial, radial-inflow and radial-outflow turbines are investigated for various low-power generation(1-15 kW) applicationslike domestic, rural and remote off-grid communities. This work presents a new integrated mathematical model for developing efficient axial, radial-inflow and radial-outflow (centrifugal) turbines with low mass flow rate (0.1-0.5 kg/s) using a range of organic working fluids (R14lb, R1234yf, R245fa, R365mfc, isobutene, n-butane and n-pentane). The newmathematicalapproachintegrates mean-line design and 3D CFD analysiswith ORC modelling.RANSequationsfor three-dimensionalsteady state and viscousflow were solved with k-ro SST turbulencemodel to predict 3D viscous turbulent flow and turbine performance.With the aim of enhancingthe ORC performanceby increasing its pressure ratio, novel small-scaletwo-stageaxialandradialoutflowturbinesaremodelled and compared with single-stageaxial, radial-inflowand radial-outflowturbines. New performancemaps in terms of isentropic efficiency and power output for each turbine configuration are developed in terms of expansion ratio, mass flow rate, rotational speed and turbine size. Noveloptimizationtechniqueusingmulti-objectivegeneticalgorithmwasappliedtooptimize small-scale single stage axial, radial-inflow and radial-outflow turbines with this flow rate. Experimental study of the ORC radial-inflow turbine was carried out.

[发布机构] University:University of Birmingham;Department:School of Engineering, Department of Mechanical Engineering

[关键词] T Technology;TJ Mechanical engineering and machinery