Formulation and analysis of the heat pipe turbine for production of power from renewable sources

The heat pipe turbine or thermosyphon Rankine engine is a new concept for p ower generation using solar, geothermal or other available low grade heat s ources. The basis of the engine is the thermosyphon cycle, with its excelle nt heat and mass transfer characteristics, modified to incorporate a turbin e in the adiabatic region. The basic configuration is a closed vertical cyl inder functioning as an evaporator, an insulated section and a condenser. T he turbine is placed in the upper end between the insulated section and con denser section, and a plate is installed to separate the high pressure regi on from the low pressure region in the condenser. Conversion of enthalpy to kinetic energy is achieved through the nozzles. The mechanical energy deve loped by the turbine can be converted to electrical energy by direct coupli ng to an electrical generator. This paper describes the development of the heat pipe turbine from concept to reality, a series of development steps taken to optimise the design and manufacture. Also in this paper, attempts have been made to provide relatio nships for the developed power in terms of the geometric and thermodynamic parameters and to discuss limitations on the efficiencies of these turbines . (C) 2001 Elsevier Science Ltd. All rights reserved.