Dynamic performance modelling and controller design of a mini-scale organic Rankine cycle unit for heavy duty vehicles (DYNCON-ORC)


Internal combustion engines of heavy duty vehicles convert only approximately 40 % of the combustion heat to mechanical power, while rest of the heat is rejected into the environment as waste heat. An organic Rankine cycle unit that recovers part of this waste heat is expected to reduce the fuel consumption and carbon dioxide emissions by about 3-5 % of the heavy duty vehicle. However, the waste heat from internal combustion engines of heavy duty vehicles is characterized by large fluctuations in load, making it a challenging task to control an organic Rankine cycle unit in an efficient, safe and cost effective manner. A few prototype of mini organic Rankine cycle units for truck applications have been tested, but no commercial products are available; the aforementioned control challenge being the major barrier for their commercialization. The primary objective of DYNCON-ORC is to develop an appropriate controller for a mini-scale organic Rankine cycle unit for waste heat recovery from internal combustion engines of heavy duty vehicles. Advanced numerical models of the organic Rankine cycle unit including its components will be developed for simulation of the steady state and dynamic operational conditions. Based on the results of the dynamic model, a non-linear model predictive controller will be designed and optimized. The numerical models will be experimentally validated and implemented on a real organic Rankine cycle system. Through the collaboration with international, world-leading partners from industry and academia it is ensured that the project will be successfully completed and that the findings of the project will be transferred to and implemented in industry. In broader terms, the project will contribute to the development of a more efficient energy system for vehicles, reducing the fuel consumption and carbon dioxide emissions of the transportation sector, thus helping to attain socioeconomic and environmental targets in context of the EU 2020 vision.


The primary goal of the DYNCON-ORC is to develop a control strategy and to design a non-linear model predictive regulator to control a mini-scale ORC unit for the waste heat recovery from an ICE of heavy duty vehicles. In order to achieve the primary goal of the project, the following tasks will be accomplished:

  1. Develop a state-of-the-art component level dynamic model of the mini ORC unit for heavy duty vehicles applications with a narrow focus on low model complexity, low computational time, and sufficiently high accuracy.
  2. Validate and tune the dynamic model of the mini ORC using an experimental ORC test rig (connected to a hot gas generator providing the ICE heat source profiles) at University of Liege, imitating the full operational range of a heavy duty vehicle engine for which data will be provided by Scania.
  3. Design, optimize and build a non-linear model predictive controller driving an ORC module following an engine load profile of a heavy duty vehicle, maximizing the net power while ensuring safe operation. Finally, implement the controller on an ORC test rig in order validate the numerical model of the controller and to evaluate the performance of the controller on a real system.


Fredrik Haglind
DTU Construct
+45 45 25 41 13