Objectives

This project aims to develop new knowledge regarding the development of improved, miniaturized components for small heat pumps and their interaction at the device level, assuming the use of the lowest possible refrigerant charge, and to disseminate this knowledge widely among relevant national target groups. The main focus of national R&D activities is on heat exchangers, compressors, and selected system aspects.

Contents

The planned national project activities include the development of a systematic overview of heat exchangers produced in the DACH region that are best suited for use in miniaturized heat pump systems due to their compact design, such as microchannels, mini tube bundles, etc. Potentially suitable heat exchangers are evaluated in terms of relevant technical characteristics, compatibility with natural refrigerants, especially R290, availability, and possible application scenarios.

Moreover, a systematic survey of the requirements of national heat pump manufacturers for compressor technologies (pressure, temperature, etc.) and comparison with commercially available compressors for specific areas of application with natural refrigerants (e.g., R290 propane, R600a isobutane) is conducted.

Compressor development needs are identified, considering further results and findings from (inter)national projects, and ideally initiation of R&D projects with national heat pump manufacturers.

Furthermore, selected aspects of the system design of small heat pumps with a focus on their influence on system performance and their treatment will be analysed. Finally, various dissemination and communication measures will be taken to spread the know-how gained in the national project as well as the results and findings from the international annex project in the national heat pump industry.

Expected results

The planned national results include a report with an overview of heat exchanger types manufactured in the DACH region that can be used efficiently with natural refrigerants in small heat pumps from a techno-economic perspective. Compressor requirements of small and medium-sized national heat pump manufacturers will be studied, compressor technologies available on the market will be characterized, and the resulting R&D needs for compressors for small heat pumps will be evaluated.

Findings on the influence of alternative component positioning on the refrigeration circuit will be reported, examining the filter dryer as an example.

Finally, a report with findings on the effects of selected system design aspects (e.g., serial/parallel connection of several modules) on the system performance of a small heat pump will be prepared.

Austria, China, Sweden (Operating Agent)

Project lead

Dr. Tilman Barz
AIT Austrian Institute of Technology GmbH
Giefinggasse 2, 1210 Wien
E-Mail: Tilman.Barz@ait.ac.at
Web: ait.ac.at

Project partner

Ao. Univ.-Prof. DI Dr. techn. René Rieberer
TU Graz - Institut für Wärmetechnik
Inffeldgasse 25/B, A-8010 Graz
E-Mail: rene.rieberer@tugraz.at
Web: tugraz.at