A dynamic lumped parameter model of injection cooling system for liquid subcooling

An injection cooling system for storage of a liquid has been studied theoretically. Cooling of the liquid is performed by passing a gas through the liquid; as the liquid evaporates into the gas phase, latent heat is transferred from the liquid resulting in liquid cooling. Among various storage methods, liquid subcooling by gas bubbling offers a simple but efficient solution, especially when short term liquid storage at low subcooled condition is needed at low cost. This type of cooling process is a case of simultaneous interphase heat and mass transfer. Heat exchange between the liquid and the surroundings also determines the overall efficacy of the process. Consideration of the two phase transport phenomena makes the theoretical analysis of this process very complex. However, for quick evaluation of the storage performance of such a system, a realistic but simplified model has been developed without involving the complex transport phenomena-based conservation equations. This model would also help in evolving a preliminary design of injection cooling system, as well as in assessing the effects of various operating and design parameters on the system performance. Such a model has been presented in this paper. Simulation runs were carried out and the model has been validated considering storage of liquid oxygen. Satisfactory match between the limited experimental data available in the literature with the model predictions has been found, thereby supporting the usability of the model for the said purpose.