at Google ScholarTitle data
Jeßberger, Jaromir ; Heberle, Florian ; Brüggemann, Dieter:
Experimental Optimization of the Part Load Behaviour of a High-Temperature Heat Pump.
2025
Event: 8th International Seminar on ORC Power Systems
, 09.-11.09.2025
, Lappeenranta.
(Conference item: Other
Event type,
Speech with paper
)
Abstract in another language
In order to achieve the objectives of decarbonization, it is imperative to integrate high-temperature heat pumps (HTHPs) into industrial energy systems and district heating networks. This transformation is a pivotal step in establishing a global carbon-neutral system. Part load behaviour, suitable compressor designs or the choice of working fluids are elevant research tasks. In this context, a HTHP test rig was introduced in previous studies. This test rig features comprehensive measurement equipment, an internal heat exchanger, water-cooled cylinder heads, and software-controlled water circuits. The present study aims to optimize the part load behaviour of the test rig within a compressor speed range of 758 rpm to
2100 rpm. Boundary conditions are employed in this study to simulate an industrial waste heat recovery scenario, with a heat source temperature of 60 C and a heat sink temperature of 120 C. The temperature difference at the heat source was set to 10 K and at the heat sink to 60 K. To adjust the part load behaviour, an electronic expansion valve is used to control the superheat of the refrigerant at the outlet of the evaporator. The suction gas temperature of the compressor is adapted by an oversized internal
heat exchanger (IHX) combined with a reconnected bypass. Additionally, water-cooled cylinder heads are employed to recover the compressor’s waste heat. Utilizing a net frequency of 50 Hz, the compressor speed is 1517 rpm, which results in a coefficient of performance (COP) of 2.75, with a superheat at the outlet of the evaporator of 5 K and an IHX-bypass position leading to a suction gas superheat of 20 K in the design point. It is evident that by adapting the heat exchanger surface area of the IHX by changing the bypass position and adopting of a superheat after the evaporator to 8 K, a 12.5 % increase in the COP can be attained in the design point. This methodological approach was employed in the analysis of all operation points at 5 Hz increments ranging from 25 Hz to 70 Hz in this study. The COP increase is between 6 % and 22 % depending on the operation point.
Further data
| Item Type: | Conference item (Speech with paper) |
|---|---|
| Refereed: | Yes |
| Additional notes: | Paper ID: 288 |
| Institutions of the University: | Faculties > Faculty of Engineering Science > Chair Engineering Thermodynamics and Transport Processes Faculties > Faculty of Engineering Science > Chair Engineering Thermodynamics and Transport Processes > Chair Engineering Thermodynamics and Transport Processes - Univ.-Prof. Dr.-Ing. Dieter Brüggemann Profile Fields > Emerging Fields > Energy Research and Energy Technology Research Institutions > Research Units > Zentrum für Energietechnik - ZET |
| Result of work at the UBT: | Yes |
| DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
| Date Deposited: | 28 Oct 2025 08:59 |
| Last Modified: | 28 Oct 2025 08:59 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/95021 |