The precision of several methods for computing the chemical potential by molecular simulation is investigated. The study does not apply molecular simulation to the analysis but instead works with models of the simulation process. These models enable the variance of the chemical potential to be computed accurately and very quickly and thereby permits the methods (freeenergy perturbation, expande...

This report presents the application of polynomial regression for estimating free energy differences using thermodynamic integration data, i.e., slope of free energy with respect to the switching variable lambda. We employ linear regression to construct a polynomial that optimally fits the thermodynamic integration data, and thus reduces the bias and uncertainty of the resulting free energy est...

Energy, exergy and exergoeconomic (3E) evaluation are performed to assess the performance of a NH3/H2O cycle integrated with parabolic trough solar collectors (PTSC). To provide continuous electricity produced by generator when solar beam radiation is insufficient a stabilizer temperature subsystem is utilized. The major thermodynamic parameters and climate conditions variations are selected to...

The UV flash problem is ubiquitous in process engineering for both dynamic simulation and dynamic optimization of vapor-liquid equilibrium processes. Such vapor-liquid equilibrium governed processes include flash separators, distillation columns, as well as enhanced oil recovery strategies for production of oil from an oil reservoir. A core modeling element in all these applications is the UV f...

often in modeling the engineering optimization design problems, the value of objective function(s) is not clearly defined in terms of design variables. instead it is obtained by some numerical analysis such as fe structural analysis, fluid mechanic analysis, and thermodynamic analysis, etc. yet, the numerical analyses are considerably time consuming to obtain the final value of objective functi...

an irreversible stirling heat pump cycle using ferromagnetic materials as a cyclic working substance is established. the influences of finite-rate heat transfer, heat leak, regeneration time, regenerative lossand the internal irreversibility on the cyclic performance of magnetic heat pumps are taken into account. on the basis of the thermodynamic properties of ferromagnetic materials, the perfo...

removal of cesium from synthetic aqueous solution through adsorption on vermiculite, under batch equilibrium experimental condition at six initial values of ph (3, 4, 6, 9, 11 and 12) and five temperatures (25, 50, 75, 85 and 95 °c) has been investigated. it is necessary to propose a suitable model for a better understanding of the mechanism of cesium adsorption on vermiculite. for this propose...

Thermodynamic models and experimental data exhibit the usual systematic and random errors. The severity of their errors depends on their use, such as for process calculations in a process simulator. Similarly, the value of better thermodynamic models andror data should be measured with reference to such use. We have developed techniques for quantification of such thermodynamic-induced process u...