INFLUENCE MOISTURE FORMATION ON CYLINDER SURFACE ON THE DETERMINATION OF HEAT TRANSFER COEFFICIENT AIR DURING APPLICATION OF THE METHOD OF MELTING ICE
Circular cylinders with cross-flow are a component of many technical devices in power engineering, heat engineering and chemical technology.
For the intensification of external heat exchange, various types of ribs are widely used, the use of which is associated with a large metal capacity of the equipment. Application of holes on the heat exchange surface can significantly improve the thermohydraulic and mass-grossing characteristics of heat and mass equipment. A simple and effective way of intensifying heat transfer is the spiral groove on the outer surface of the pipe.
The purpose of this work is to develop a method for determining the average coefficient of heat transfer by the method of melting ice, taking into account the moisture that falls on the surface of the cylinder-calorimeter. The research was carried out in the range of the Reynolds number change, calculated from the outside diameter of the pipe, from 2000 to 17000.
In this paper, the method of determining the average coefficient of heat transfer by the method of melting of ice at the cross-flow of a round cylinder is specified. It is shown that ignoring the air humidity flowing through the cylinder-calorimeter can lead to a large error in determining the average coefficient of heat transfer, especially when air humidity is more than 53%.
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