An Experimental and Analytical Investigation of Ice Formation From a Circular Water Jet Impinging on a Horizontal Cold Surface

The transient freezing of water impinging vertically on a subzero disk through a circular jet is studied experimentally to determine the interaction of the fluid flow and the solidification process. Experiments are performed over a range of the jet Reynolds number (1600 < Re_i < 3500) based on the average velocity and radius of the falling jet at the impingement point. For this range of Reynolds numbers, that corresponds to tube Reynolds numbers less than 1100, and in the absence of solidification, the thin liquid film is characterized by a smooth circular hydraulic jump whose diameter is measured and correlated with the jet Reynolds number. The solidification process is initiated away from the jet (i.e., outside of the hydraulic jump) and moves inward toward the jet. The formation and growth of ice on the cold surface affect the flow field over the surface. This effect manifests itself in the form of a rapid reduction of the hydraulic jump diameter accompanied by instability in its position until its complete disappearance. The effect of fluid flow on the solidification process is found to be a small reduction in the nucleation temperature. The ice layer profiles at different times for different values of jet Reynolds number, and Stefan numbers of the surface and jet are also measured and reported. An approximate model is developed for the calculation of the transient crust growth by neglecting the interaction between the flow and solidification. The predicted solid crust profiles are compared with the measured ones, and the extent of the flow-freezing interactions is discussed. The approximate model is also used for a parametric study of the problem for a constant temperature surface.