Prototype of a thermally driven heat pump based on integrated Organic Rankine Cycles (ORC)

The concept studied in this work is a low power ORC-ORC heat pump system (providing about 20 kW heat at the condenser) and that is composed of an ORC power cycle driving a reversed ORC heat pump cycle, both cycles using the same fluid. The centrifugal compressor and the radial in-flow turbine are directly coupled on the same shaft rotating on self-acting refrigerant vapor bearings. The system has the advantage of being oil-free, fully hermetic and with low maintenance costs. The paper presents the development of an ORC-ORC prototype, with HFC-134a as working fluid. The main critical parts of the system are the compressor-turbine unit, the supercritical evaporator and the pump. The selected type of heat exchanger for the supercritical evaporation is the double tube coil (DTC). A first experimental setup has been built to test the pump and the supercritical evaporator. A comparison between the results obtained with an in-house supercritical evaporator simulation program and measurements made on the DTC is presented. The design steps of the compressor-turbine are briefly presented. The compressor-turbine unit has been balanced and tested, with air, at speeds up to 140'000 rpm.


Published in:
Energy, 41, 1, 10–17
Year:
2012
ISSN:
03605442
Keywords:
Laboratories:


Note: The status of this file is: Involved Laboratories Only


 Record created 2011-11-01, last modified 2018-03-17

n/a:
Download fulltext
PDF

Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)