Absorption Refrigeration Cycles with Ammonia-Ionic Liquid Working Pairs Studied by Molecular Simulation
Tim M Becker1, Meng Wang1, Abhishek Kabra1
1Engineering Thermodynamics, Process & Energy Department, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Leeghwaterstraat 39, 2628CB Delft, The Netherlands.
Industrial & Engineering Chemistry Research
|May 12, 2018
Summary
Ionic liquids show promise for absorption refrigeration. Molecular simulations can predict their thermodynamic properties, enabling performance assessment for absorption refrigeration cycles without extensive experiments.
Area of Science:
- Thermodynamics
- Chemical Engineering
- Materials Science
Background:
- Ionic liquids are potential replacements for conventional working pairs in absorption refrigeration.
- The vast number of ionic liquids makes experimental screening infeasible.
- Computational methods offer an alternative for identifying optimal ionic liquids.
Purpose of the Study:
- To demonstrate a computational approach for evaluating ionic liquids in absorption refrigeration.
- To determine key thermodynamic properties of ionic liquids using molecular simulations.
- To estimate the performance of absorption refrigeration cycles with selected ionic liquids.
Main Methods:
- Molecular simulations were employed to calculate solubility, heat capacity, and heat of absorption.
- A model of the absorption refrigeration cycle utilized these properties to estimate performance metrics.
- Two ionic liquids, [emim][Tf2N] and [emim][SCN], were studied with ammonia as the refrigerant.
Main Results:
- The study successfully predicted thermodynamic properties of ionic liquids relevant to absorption refrigeration.
- Estimated circulation ratio and coefficient of performance were obtained using simulated data.
- Comparison with traditional methods highlights the potential of simulation-based approaches.
Conclusions:
- Molecular simulations can effectively predict thermodynamic properties for absorption refrigeration cycle performance.
- Accurate prediction of cycle performance is contingent upon the quality of force fields used in simulations.
- This computational approach offers a viable alternative to extensive experimental screening for ionic liquid selection.
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