Methodology of calculation of multiplex heat exchang apparatus with cross flow and mixing in heat carriers

Abstract

The most efficient apparatus are known to be heat exchangers with classic countercurrent flow of heat carriers. However, this current scheme is rarely possible to create in an apparatus. In many cases cross flow heat exchangers are more acceptable in terms of efficiency of heat emission from the outer surface of the wall. Therefore cross flow if used which is within the identical surface area and heat-transfer rate in disadvantage in comparison with the classic countercurrent scheme. In this case multiple passes mixed diagram are mainly used where with sufficient number of cross flow passes reciprocal flow of heat carriers is close to the classic countercurrent. The most widespread assembling design of heat exchangers is complex and mixed current design. Unlike the simple mixed design one of the heat carriers moves as split flow lines through the full length and it does not interfuse between the passes and a heat carrier, which is inside as a rule within one pass and flows as split flow lines and it interfuses between the passes. In such a way the design of the mixed flow will be complex where every pass (section) is a complex cross flow diagram. Heat exchangers that are under analysis are widely spread in the different fields of the economy. That is why receiving more accurate and perfect methods and techniques of their research and analysis is an urgent task.