(Advanced Thermodynamic Cycles Utilizing Low-temperature Heat Sources)


The objective of THERMCYC is to: 

  • Identify target properties for working fluids of thermodynamic cycles

  • Develop property prediction models for the estimation of working fluid properties

  • Develop frameworks for computer-aided molecular design of working fluids

  • Develop frameworks for computer-aided mixture design of working fluidsIntegration
    of working fluid development and process design


Organic rankine cycle and heat pumps are technology on thermodynamic cycles which consist of a compressor, a turbine and two heat exchangers (evaporator and condenser). The working fluid circulates through these components and changes its state from both liquid and gas phases. In order to optimize industrial heat pump processes for adding and removing heat from the cycle, the influence of the working fluid is vital. This project studies the characteristics of working fluids using Multi-criteria database search and Molecular Design principles to generate, test and evaluate promising pure component/mixture candidate as process fluids to help optimize cycle design and performance.

The Project 

Low-temperature heat sources are available in many applications, ranging from waste heat from marine diesel engines, industries and refrigeration plants to biomass, geothermal and solar heat sources. There is a great potential for enhancing the utilization of these heat sources by novel cycle design and use of multi-component working fluids. These advancements will not only improve the performance of existing technologies, but also enable the utilization of low-temperature heat sources, which are currently not utilized due to technical or economical infeasibility.

In this context we address advancements in and the use of novel pure component working fluids and mixtures. Both power and heat pump are considered for utilization of heat to cover the complete temperature range of low temperature sources. The work includes prototype design, numerical simulation, and use of advanced methods for thermodynamic analyses and working fluid design. We develop a systematic approach to derive the optimum thermodynamic cycle and working fluid, considering a range of relevant design criteria for a given application.
The selection of a suitable working fluid for thermodynamic cycles is important and has to satisfy many requirements ranging from heat transfer ability to safety and environmental constraints such as ozone depletion potential (ODP) and Global Warming Potential (QWP) among others. The fluids must also be chemically stable at any conditions of use, meaning no reaction/oxidation to form by-products, and need to be efficient. The aim is to develop a truly predictive and innovative methodology for designing novel working fluids for particular needs. The methodology consists of databases, models (physical, chemical and environmental properties of pure components & mixtures of working fluids), algorithms to automatically generate molecular structures & to mixture/blend design, uncertainty analysis, methods and tools.

THERMCYC Project Website

For more information, please visit the THERMCYC project website.


John Michael Woodley
DTU Kemiteknik
45 25 28 85