Postdoctor in Thermal Cold Storage and Enhanced Heat Transfer in R744 Vapour Compression Systems

Trondheim, Norway
05 Apr 2018
End of advertisement period
24 Apr 2018
Contract Type
Full Time

Faculty of Engineering 
Energy and Process Engineering


A postdoctoral position is available at the Department of Energy and Process Engineering (EPT) within the Refrigeration research group on the topic of "Enhanced heat transfer and thermal cold storage in R744 vapour compression systems ". The appointment has a duration of 2 years.

The Refrigeration research group has a well-established expertise and network as regards of vapour compression systems applying natural working fluids for various applications within different industrial sectors. In close cooperation with SINTEF the group is involved in several national and international research projects.

The background for the research work is that supermarkets and industrial process plants rely on the electricity provided by the grid to solve complimentary demands: HVAC (heating, ventilation and air conditioning) and refrigeration, as their main energy systems inside the building. Currently it is not common to apply thermal storage devices which allow peak shaving of the power consumption to avoid additional energy costs due to high power demand periods. Around 5% of the global electric energy is required by units controlling the temperature around foodstuff exposed to customers. There is also a need for improving the energy efficiency of the main energy systems (AC, refrigeration and heat pumps in process plants), which require a significant amount of energy for their operation. There is a request from end-users to become more independent from the power grid, due to high power peak costs and in cases of power cut-off, especially in sparsely populated areas. This issue becomes also important in countries where electricity is not guaranteed 24/7. For a supermarket, the impact on customers is reflected on the quality of the food products, which can be also affected by the temperature fluctuations due to defrosting cycles and peak demands when refilled with warm items. This will also have an impact on the quality of foodstuff, as the temperature fluctuations reduces the shelf life of the products.

The scope of the research work is the theoretical study and CFD modelling of the heat transfer and pressured drop phenomena for a three fluid heat exchanger-storage unit. Thermal storage, with natural phase change materials (nPCMs), to be placed inside display cabinets or other process equipment for short term thermal energy storage (ex.: modelling of turbulence at micro-textured heat-exchanger parts, non-equilibrium solidification process of the PCM inlay with nucleation delay). The theoretical results will be validated with experimental investigations conducted in the advanced R744 laboratory at NTNU.


The candidate should hold a PhD related to refrigeration systems. The candidate has to be able to perform the above-mentioned CFD simulations based on previous documented experience. Expertise and experience from laboratory work related to heat transfer are an advantage, too.

Excellent English skills, spoken and written, are required. Applicants from non-English-speaking countries outside Europe must document English skills by an approved test. Approved tests are TOEFL, IELTS, Cambridge Certificate in Advanced English (CAE) or Cambridge Certificate of Proficiency in English (CPE).


Postdoctoral candidates are remunerated in code 1352, and are normally remunerated at gross from NOK 485,700 per annum before tax. There will be a 2% deduction to the Norwegian Public Service Pension Fund from gross wage. The appointment of the Postdoctoral fellows will be made according to Norwegian guidelines for universities and university colleges and to the general regulations regarding university employees.

The Postdoctoral fellowship is awarded for 2 years.

For further information, please contact Professor Armin Hafner, e-mail Please observe that applications should not be sent to this e-mail address.

The engagement is to be made in accordance with the regulations in force concerning State Employees and Civil Servants. The positions adhere to the Norwegian Government's policy of balanced ethnicity, age and gender. Persons with immigrant background are encouraged to apply. NTNUĀ“s objective is to increase the number of females in scientific positions. Female applicants are therefore encouraged to apply.

The latest start up time for the position is end of June 2018.

The application

The application must contain information of educational background and work experience. Certified copies of academic diplomas and certificates, copies of transcripts and two reference letters should be enclosed. Applications with CV, grade transcripts and other enclosures should be submitted via this webpage at Mark the application with IV-131/18.

Application deadline is April 24th, 2018.

According to the new Freedom of Information Act, information concerning the applicant may be made public even if the applicant has requested not to be included in the list of applicants.


  • Deadline Tuesday, April 24, 2018
  • Employer NTNU - Norwegian University of Science and Technology
  • Website
  • Municipality Trondheim
  • Place of service Department of energy and process engineering
  • Jobbnorge ID 150427
  • Internal ID 2018/9618
  • Scope Fulltime
  • Duration Temporary


  • Applications on this job are registered in an electronic form on
  • You must complete: Standard CV
  • Please refer to where you first saw this job advertised!