Heat transfer enhancement in cool-thermal discharge systems from ice melting with time–velocity variations

A mathematical model for the cool-thermal discharge systems which produce chilled air by melting ice to supply on-peak daytime air-conditioning needs under time-velocity variations and external recycle was developed. The model resolves the moving liquid–solid interface problem with the integral boundary-layer analysis method. For specified target of the outlet air temperature, time variation of the air velocity can be theoretically predicted for the given ambient air inlet temperature functions. The heat transfer efficiency can be improved by employing the external recycle design under the expense of power consumption. The analysis indicates that the recycle effect is more significant for the case with higher outlet air temperature target. Besides, optimal reflux ratio exists for the analyzed system.