Experimental Investigation on Cryogen Saving through Helical Transfer Lines With Varied Orientation

The demand and application of cryogenic fluids is constantly increasing. Production of these cryogenic fluids is an energy intensive process. Chilldown of the system prior to its operation is inevitable for the safe and manageable performance. This is accompanied with a large amount of cryogenic fluid loss that increases with the increase in chilldown time taken. This process, if done poorly, will cause wastage of cryogen which requires a lot of energy to produce. Therefore, saving cryogen in chilldown can save energy. In this study, effect of geometry and fluid flow pattern on chilldown characteristics of transfer lines has been investigated into. Comparative experimental study was conducted on straight and helically coiled transfer lines with 3 different orientation namely, horizontal, vertically upward and downward under continuous flow. It was found that helical coils could be chilled down faster. The comparison of chilldown time with continuous flow in straight and helically coiled tube was conducted using CFD simulation where, the pulsed flow pattern was identified to be more efficient for higher time period.