Experimental Investigation on Freezing of Water Falling Film on Vertical Bank of Cold Horizontal Tubes

Abstract

The heat exchangers for ice formation on tube essentially consists of cold pipes submersed in stagnant water or in a cross flow of water. The heat exchanger considered here is a falling film one. Water falling film falls down over a set of vertical in-line cold horizontal tubes. The falling film main modes are droplets, jets, and sheet depending on its flow rate. The tubes are internally cooled by a controlled subzero temperature coolant. The coolant passes through the pipes in parallel. Water falling film freezes gradually outside the test tubes. The quantity of ice formed on the test tubes is observed, photographed, and measured at different times for different falling film modes. It has been noticed that the rate of ice formation decreases with time as ice accumulates on the test tubes. The overall heat transfer coefficient decreases as more ice accumulates on the test tubes.