The Paul Scherrer Institute PSI is the largest research institute for natural and engineering sciences within Switzerland. We perform cutting-edge research in the fields of future technologies, energy and climate, health innovation and fundamentals of nature. By performing fundamental and applied research, we work on sustainable solutions for major challenges facing society, science and economy. PSI is committed to the training of future generations. Therefore, about one quarter of our staff are post-docs, post-graduates or apprentices. Altogether, PSI employs 2200 people.

Air pollution is a major global health issue, causing around 10 million deaths each year. Aerosols, or particulate matter PM, are a significant contributor to air pollution, and can come from both natural sources (e.g. forests, dust) and anthropogenic sources (e.g. traffic, biomass burning). To better understand and predict the concentration of PM in urban environments, we plan to conduct an experimental study using state-of-the-art water and wind tunnels at the Swiss Federal Laboratories for Materials Science and Technology EMPA, which is our partner institution. The goal of this study is to gather data that will be used to develop and validate a numerical CFD model that can accurately predict PM concentrations with high spatial and temporal resolution.

For the Laboratory for Reactor Physics and Thermal-Hydraulics we are looking for a
Postdoctoral Fellow
Experimental and Numerical Investigations of Pollutant Transport in a Model City
Your tasks
We are seeking a person to join our team and contribute to the research in the area of aerosol transport. Your responsibilities will include:

  • Characterizing and specifying the experimental set-up and particle transport test matrix
  • Designing mock-ups of scaled-down urban environments
  • Conducting experimental tests to cover relevant turbulence and particle size ranges
  • Analysing experimental results, including processing of Particle Image Velocimetry PIV data, and creating a benchmarking database for CFD code validation
  • Contributing to the development of a CFD particle transport model based on experimental results
  • Collaborating with the water and wind tunnel team at EMPA
  • Collaborating with scientists in the area of atmospheric chemistry to gather and prepare the necessary city-scale data
  • Collaborating with the computational fluid dynamics CFD modellers for modelling and validation of the transport of aerosols over urban environments
  • Publishing research results in relevant journals and conferences as well as and preparing technical reports
  • Bachelor’s and Master’s student supervision
Your profile
  • You have a PhD degree in Mechanical Engineering, Atmospheric Sciences or other related scientific field
  • You are highly motivated and skilled experimentalist with a solid background in fluid flow field characterization
  • You have practical experience in large-scale Particle Image Velocimetry PIV and data analysis, also a working knowledge in particle generation and characterization
  • You have good understanding and knowledge of CFD simulations, and ideally experience in the use of CFD codes
  • You are proficient in both spoken and written English
The main research work will be located at PSI, and the experimental work will be performed at EMPA institute; thus, you are willing to commute between PSI and EMPA institute.
We offer
Our institution is based on an interdisciplinary, innovative and dynamic collaboration. You will profit from a systematic training on the job, in addition to personal development possibilities and our pronounced vocational training culture. If you wish to optimally combine work and family life or other personal interests, we are able to support you with our modern employment conditions and the on-site infrastructure.

Your employment contract is initially limited to 1 year, and may be extended up to 2 years.

For further information, please contact Dr Omar Al-Yahia, phone +41 56 310 27 84, email

Please submit your application online by 28 February 2023 (including list of publications and addresses of referees) for the position as a Postdoctoral Fellow (index no. 4103-00).

Paul Scherrer Institut, Human Resources Management, Serdal Varol, 5232 Villigen PSI, Switzerland