Molecular simulation of NH3/IL mixture for absorption refrigeration cycle

A molecular based Monte Carlo (MC) simulation method is used to predict the performance of the absorption refrigeration cycle involving NH3/IL (refrigerant/absorbent) pair as a working fluid. To investigate the thermodynamic performance of the absorption refrigeration cycle, various properties such as density, excess enthalpy or absorption heat, heat capacity and solubility of refrigerant in the absorbent are required. For this reason, MC simulations as an alternative to experiments, are used to compute the required properties. MC simulations in the osmotic ensemble are used to compute the solubility of NH3 in ILs. The ideal part of the heat capacity of pure IL is computed using quantum mechanical calculations and the residual part along with the density are computed using MC simulations in the NPT ensemble. The excess enthalpy for the mixture is calculated using MC simulations in the osmotic ensemble in combination with the NPT ensemble. The simulations are performed at temperatures ranging from 303 K to 393 K and pressures ranging from 4 to 18 bar. The performance parameters such as Coefficient of Performance (COP) and circulation ratio (f) of NH3 paired with two ILs, [emim][Tf2N] and [emim][SCN], are investigated using MC simulations and compared with the results obtained from correlated experimental data. The results from the MC simulations are in reasonable agreement with those obtained from the correlated experimental data. Hence, MC simulations can be used as an inexpensive alternative for preliminary design considerations involving potential working fluids for absorption refrigeration cycles in the absence of available experimental data.Mechanical, Maritime and Materials EngineeringProcess and Energy (P&E