Prediction of solid-liquid equilibrium state for light alkane mixed fluids and associated densification effect
A comparison study indicates that the regular solution model has the highest accu-racy in simulating the freezing temperature of mixed propellant when compared to other models.Therefore,this model is used to predict the freezing temperatures and densification effect of meth-ane-ethane and methane-propane binary systems.It is found that methane-ethane system reaches the lowest freezing temperature of 72.90 K when the methane's molar fraction is 0.72 in the mix-ture system.Compared to the pure methane at its triple point,the density increase rate of the mix-ture is 21.62％.For the methane-propane system,the lowest solidification temperature of 71.55 K occurs at the methane's molar fraction of 0.66,and the density increase rate is 34.48％.Moreo-ver,an ideal solution model is used to predict the performance of methane-ethane-propane ternary system.It is found that when the mixing ratio is 0.63∶0.17∶0.20,the solidification temperature re-duces to 63.11 K,and the subcooling potential of methane propellant could be further improved.In addition,three-phase diagrams of the mixed fluids are given,which provide theoretical support for future the subcooling preparation and deep densification of liquid methane propellant.
solid-liquid equilibriumeutectic pointdensificationregular solution model
万方数据
维普
