A Programming Design for Calculating Suitable Insulation Thickness And Heat Transfer Characteristics of an Insulated Rectangular Duct With One To Three Insulated Layers

摘要

This study is on programming a user-friendly code to calculate suitable insulation thickness and relative heat transfer characteristics for an insulated hot/cold rectangular duct involving one to three different insulation layers. Users simply input the required data, the inner fluid and the ambient conditions of the insulated duct, the sizes of duct, the properties of insulation materials under the specified conditions (uncondensed surface for the cold duct or maximum safe surface temperature for the hot duct), step by step, then the optimum insulation thickness, reliable heat transfer rate, minimum surface temperature of a cold duct/maximum surface temperature of a hot duct and insulation effect can be easily computed. Comparing with the inaccurate insulated thickness and relative unreliable heat transfer characteristics calculated from the PTR model, the employment of this code can greatly enhance the quality and stability of a system design involving insulated rectangular ducts.