Modelling ice generation in a cooled pipe containing a flowing brine stream

Conventional methods of making ice can be inefficient in the use of energy, especially when commercial methods either adopt low heat rejection temperatures to increase the rate of ice formation or use freeze-melt operations to reduce the mechanical complexity of the ice making equipment. Ongoing work has shown that it is possible to generate ice rapidly with a relatively low degree of subcooling, provided the heat transfer area is large[1]. This has led to two methods being investigated; the first uses make use of direct contact heat transfer where the water to be frozen is directly injected into a liquid at a temperature which is below the freezing point of water. The second is uses conventional heat exchange through a solid separating a cold (heatsink) fluid from the water to be frozen [2]. This is developed into a continuous system where the water is made to flow continuous through a plastic pipe while the outside of the pipe is maintained below the freezing point of water. The work reported here is modelling the heat transfer and phase change which occur in this pipe-flowing system.