Proceedings of the
5th International Seminar on
ORC Power Systems
9 - 11 September 2019, Athens Greece
Home Program Author Index Search

Experimental Evaluation of R1336mzz(Z) as Low GWP Replacement for R245fa in a Scroll Expander


Go-down orc2019 Tracking Number 44

Presentation:
Session: Session 6C: Volumetric Expanders (2)
Room: Templar's
Session start: 09:00 Wed 11 Sep 2019

Matthias Welzl   matthias.welzl@uni-bayreuth.de
Affifliation: Chair of Engineering Thermodynamics and Transport Processes (LTTT), Center of Energy Technology (ZET), University of Bayreuth
Florian Heberle   florian.heberle@uni-bayreuth.de
Affifliation: Chair of Engineering Thermodynamics and Transport Processes (LTTT), Center of Energy Technology (ZET), University of Bayreuth
Theresa Weith   theresa.weith@uni-bayreuth.de
Affifliation: Chair of Engineering Thermodynamics and Transport Processes (LTTT), Center of Energy Technology (ZET), University of Bayreuth
Dieter Brüggemann   dieter.brueggemann@uni-bayreuth.de
Affifliation: Chair of Engineering Thermodynamics and Transport Processes (LTTT), Center of Energy Technology (ZET), University of Bayreuth

Topics: - Experimental activities and techniques (Topics), - Working Fluids, including mixtures (Topics), - Volumetric expanders (Topics), - Oral Presentation (Preferred Presentation type)

Abstract:

Hydrofluoroolefin (HFO) refrigerants are promising low global warming potential (GWP) alternatives to the currently used hydrofluorocarbons (HFCs) in Organic Rankine Cycle (ORC) systems. This study led the focus on the experimental evaluation of the novel HFO R1336mzz(Z) as a low GWP replacement for the HFC R245fa. The investigated scroll expander is a semi-hermetic oil-free expander with a rated power of 1 kW and a built-in volume ratio of 3.5, which is magnetically coupled with a 1 kW permanently excited synchronous generator. For the determination of the expander mechanical power output, a contactless torque sensor is integrated. The experimental investigation involved measurements at eight different operating conditions for the working fluids R245fa and R1336mzz(Z), varying the saturation temperature, the scroll expander rotational speed, and the pressure ratio. The maximum mechanical isentropic efficiencies of 58.9 % for R245fa and 57.0 % for R1366mzz(Z) were obtained at a saturation temperature of 90 °C. For all variations, the mechanical isentropic efficiency for R1366mzz(Z) is between 0.9 % and 6.2 % lower compared to R245fa. The experimental evaluation indicates, that R1336mzz(Z) is a suitable low GWP replacement for R245fa with slightly lower scroll expander efficiencies.