Abstract

The paper deals with the problem of the influnce of inert gases, vapour superheating and  fouling on condensation heat transfer in power plant heat exchangers. The performance estimation of a recuperative heat exchanger under conditions of fouling and presence of inert gases and vapour superheating is extremely important for the diagnostic codes of the turbine units. Basing on the one dimensional model the influence of fouling and air-concentration on the distribution of both the pertinent heater temperatures and heat flux was investigated. It appeared that inert gases play a dominant role in the case when its concentration is sufficiently high. lt may be concluded that the proposed 1D model provides a very efficient method for heat tansfer evaluation of heat exchangers. The effect of a strong vapour superheating on performance of heat exchanger has been discussed. It may be concluded that non-conderrsation zone in these heaters depends not only on vapour superheating but also on the heat transfer surface area.