Adiabatic calorimetry

Adiabatic, or, more precisely, pseudo-adiabatic calorimetry is one of the main experimental methods used for assessment of reactive hazards in general and one of the most typical methods applied for getting data for emergency relief systems (ERS) design. Nowadays adiabatic calorimentry is also successfully applied for assessing hazards of Li-Iion batteries.

Several manufacturers offer commercial adiabatic calorimeters. The well known examples are Fauske VSP and RSST, THT ARC, HEL Phi-TEC I and II, NETZSCH ARC and APTAC. Most resent and very promising instrument has been introduced by Omnical Inc. (USA) - it is the Differential Accelerating Rate Calorimeter, DARC, which allows running experiments at very low thermal inertia.

Adiabatic data are used either for kinetics evaluation  followed by hazard assessment, simulation of runaway and sizing vent, or for evaluation of specific information which is required for applying some or other approximate analytical methods for ERS design. Irrespective of how adiabatic data will be utilized the accuracy of all the subsequent results essentially depends on the correctness of the methods used for running experiments, processing and interpretation of data.

The theoretical basis of adiabatic calorimetry was created by Townsend and Tou and others more than 40 years ago. Since then countless papers devoted to various aspects of this method have been published. Therefore it may seem that all the problems dealing with adiabatic experiment were resolved long ago – it is safe to say that every commercial device is supplied with the methods and software for data analysis.

Nevertheless there remain still some serious issues concerning correct way of carrying out experiments and data processing that should be revised or completely reworked.

CISP experts made essential efforts towards resolving these issues and achieved many novel results that provided the solid basis for developing the analog-free methods and ARKS AC software for comprehensive analysis of adiabatic data. See, e.g. our publications

4.     Kossoy A., Belochvostov V. and Gusttin J.-L. Methodological aspects of the application of adiabatic 
        calorimetry for thermal safety investigation. J. Loss Prev. Process Ind., v.7, N.5,(1994)397.
14.   A. Kossoy, I. Sheinman, Effect of temperature gradient in sample cells of adiabatic calorimeters on
        data interpretation,  Thermochimica Acta, V 500 2010, Pages 93-99.
16.   A. Kossoy, J. Singh and  E. Koludarova, Mathematical methods for Application of Experimental
        Adiabatic data – an Update and Extension, J. of Loss Prev. in the Proc. Industries, 33 (2015) 88 - 100.
23.   A. Kossoy, Applying adiabatic calorimetry for study of energetic materials - is it possible? 
        Presentation at the 11 International HFC Symposium on Energetic Materials, Fraunhofer ICT,
        Pfinzal-Berghausen, Germany, May 13-16 2019.
24.   A. Kossoy, An in-depth analysis of some methodical aspects of applying pseudo-adiabatic
        calorimetry. Thermochimica Acta, V.683, (2020), 
   
and CISP Newsletter #9. Kinetics-based simulation approach. Advanced analysis of adiabatic data by applying ARKS AC.

Serious attention has also been paid to design of advanced methods of kinetics evaluation based on adiabatic data. They are introduced in ARKS FK and ARKS CK kinetic packages allowing a user to get reliable kinetic models for simulation-based hazard assessment.