Non Ideal Compressible Fluid Dynamics (NICFD) – Enabling Science for Turbomachinery of Next-Generation Waste Heat Recovery Systems

Project: NICFD 

Time period: June 2018 to June 2022

Funder: NWO-TTW (Grant agreement ID: 15837)

Total budget: 870,491 EUR

Short description:

In Europe alone near one third of fossil fuel related emissions stems from the industrial sector, and an even higher percentage is recorded worldwide. It is estimated that 20 to 50 % of the industrial energy input is wasted as heat in the form of hot exhaust gases or cooling water. Waste heat recovery systems are a high impact opportunity for emission-free energy conversion. However suitable thermal systems, like ORC and supercritical CO2 power plants, require novel fluid machinery capable of operating at high efficiency in the Non-Ideal Compressible Fluid Dynamics (NICFD) regime of the working fluid. The design of these compressors and turbines is extremely challenging because the working fluids, thermodynamic states and operating conditions are all different from that of common industrial practice. The physical phenomena associated with the internal flows in these machines are still poorly understood, and experimental information about fluid properties is inadequate. Their design is thus mostly performed by expensive trial and error, generally leading to poor performance and stability issues.

The goal of this project is to enable a step increase in the performance of NICFD turbomachinery by experimentally characterizing the gas dynamic behavior of dense vapors of relevant working fluids. A recently commissioned first-of-its-kind shock tube will be used to investigate non ideal effects in a controlled manner. Accurate measurements of the pressure, temperature, density and wave speed propagation will characterize the state of molecularly complex fluids. The objectives are:

  • to prove for the first time the existence of non-classical gas dynamic phenomena and determine the range of thermodynamic states where NICFD behavior manifests;
  • to validate new fluid property models;
  • to develop improved design guidelines for unconventional turbomachinery operating with dense vapors.

The outcome of the proposed research will lead to improved thermodynamic models of working fluids, and to the validation of non-ideal compressible fluid dynamics theory and numerical tools. This will enable the development of new capability for the analysis of internal fluid flows in unconventional turbomachinery.


  • Delft University of Technology – Propulsion and Power (coordinator)
  • Siemans Energy
  • Turboden Mitsubishi
  • Triogen
  • Asimptote