Flow And Heat Transfer Of Falling Film Of Concave-convex Changed Wall Surface

In this paper, the concave-convex changed wall surface is applied to falling film evaporator. This paper analyzes and studies heat-transfer property and the flow properties of the celery juice on concave-convex changed wall surface in the process of evaporation concentration. It has established heat transfer coefficient model of the concave-convex changed wall surface on the basis of predecessor's heat transfer coefficient model; Film disintegration phenomenon is analyzed and discussed in the material flowing process; At the same time, in the experiment, different operating condition heat-transfer property is studied by changing vaporization temperature, heat transfer temperature difference, material current capacity, material liquid solid shape content and the predicted value and the actual value tallies is good; The accurate number connection type is established and the actual value and the theoretical value is well; At the same time, the most superior combination values of the four factor that influence heat transfer coefficient is obtained by the method of variance analysis.The experimental result indicated that the concave-convex changed wall surface has the good heat-transfer property and flow properties; Heat transfer coefficient is high and is not easy scaling; Therefore, this structure is suitable for vacuum evaporation concentration of the vegetables juice's and it has certain application prospect in the food industry.