Thermodynamic properties of lithium bromide / water

June 1, 2017

A software package for the calculation of the thermodynamic properties of lithium bromide / water (LiBr/H2O) mixtures is currently under development.

Lithium bromide aqueous solutions have been a popular choice in the absorption cooling industry, because of their excellent thermodynamic characteristics. The use of the model is not only limited to the conventional absorption refrigeration applications but it extends well beyond unconventional operational ranges typical of various newly conceived absorption cycles, which are investigated by more and more researchers because they are relevant in terms of sustainability. Such systems, powered directly by solar collectors or by waste heat from industrial processes and prime movers, like gas turbines and reciprocating engines, yield a much higher conversion efficiency through the smart integration of energy systems.

The calculated properties are all based on a Gibbs free energy equation and are therefore thermodynamically consistent. Computations yield reliable results for solutions in the concentration range from 0 to 70% (weight) and temperatures from 0 to 210 °C with vapor pressures up to 1 MPa.

The software will be available as an Add-On to FluidProp. As FluidProp is seamlessly coupled with Cycle-Tempo, the thermodynamic properties of LiBr/H2O mixtures will be available to Cycle-Tempo simulations too, as component models have been adapted appropriately (an updated version of Cycle Tempo will also soon be released). 

The FluidProp Add-On, as well as the updated version of Cycle-Tempo, are expected to be available shortly. For more information, please contact us by sending an email to


Thermodynamic properties of hydrofluoroolefins now available in FluidProp

October 1, 2016
A new add-on to FluidProp is the Hydrofluoroolefins add-on. This add-on contains new hydrofluoroolefins, which have been developed in recent years. These fluids feature a low global warming and ozone depletion potential and can be suitable replacement candidates for foam blowing agents, fluids in heat pumps, air conditioning systems, refrigeration systems, and organic Rankine cycle systems.
The hydrofluoroolefins add-on in FluidProp contains a consistent set of complete thermodynamic models for four hydrofluoroolefins and one hydrochlorofluoroolefin. The hydro(chloro)fluoroolefins available in FluidProp are:


FluidProp name


IUPAC name




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The thermodynamic models are based on both the iPRSV and the PCP-SAFT equation of state and can therefore be used in the (free)StanMix and PCP-SAFT libraries in FluidProp.


Thermodynamic properties of cyclic siloxanes now available in the siloxanes add-on

October 1, 2016

The Linear Siloxanes add-on to FluidProp has been replaced by the Siloxanes add-on. This add-on now also contains the cyclic siloxanes D3 (hexamethylcyclotrisiloxane), D4 (octamethylcyclotetrasiloxane), D5 (decamethylcyclopentasiloxane),  and D6 (dodecamethylcyclohexasiloxane), next to the already existing linear siloxanes, MM, MDM, MD2M, MD3M,MD4M,MD5M, and MD6M.
The thermodynamic models are based on both the iPRSV and the PCP-SAFT equation of state and can therefore be used in the (free)StanMix and PCP-SAFT libraries in FluidProp. The Siloxanes add-on fee has remained unchanged.

Transport properties available for FluidProp

March 4, 2015

We proudly present a new add-on to the FluidProp family: the Transport Properties add-on. It lets you calculate the dynamic viscosity and thermal conductivity for each fluid and each thermodynamic model in FluidProp. By releasing this new add-on we're fulfilling a wish that is often expressed by our users. Please go ahead an try it. It will be available at a reduced fee in the first period.

Derivatives free for academic users

July 18, 2014

As of today, the derivatives add-on is free for academic users. We noticed that many people want to use FluidProp from the Modelica.Media library but ran into problems because they were missing the derivatives add-on. As we think that dynamic simulation with Modelica is an important development in the sector, we decided to stimulate this by giving academic users free access to the derivatives.

If you are an academic user and you want to use FluidProp 3.0 basic with the derivatives add-on, please register as academic user and then select the educational version of the derivatives add-on.

FluidProp updates

14, 2014

Asimptote contributes to feasibility study of OTEC installation

March 7, 2014

Asimptote contributed to a feasibility study for an OTEC installation for BlueRise (see We developed a preliminary design for the OTEC turbine, using our advanced optimization procedures. Contact us if you want to learn more about our expertise in this field.

New version of FluidProp

Februari 3, 2014

Today we started distributing a new version of FluidProp (version 3). The main differences with earlier versions are:

  • fully 64-bit compatible (so it also works properly on newer versions of Windows)
  • extra thermodynamic models and fluids can be purchased as add-ons to the free version
  • the helpfile has been brought up to date.

Formally, the new FluidProp is still a beta, but we have been testing it with several users for some time. So we are confident that this will prove to be a stable new version of the popular FluidProp package. For those who wish to use the old version, it is still available through

New website

December 14, 2013

We are now testing our new website. Because of the increasing traffic on our old site and continued interest, we decided to provide a better service for our users by:

  • providing all the information about our services in a concise way,
  • providing more complete information on our software products so that users can see what is in it for them,
  • providing a webshop where you can download the free versions and demo versions of our software and where you can buy the full versions and add-ons.

Please help us test the new website. If you have any comments that will help us improve, we love to here from you through our contact form.