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ISSN Online: 2377-424X

ISBN Print: 0-85295-345-3

International Heat Transfer Conference 10
August, 14-18, 1994, Brighton, UK

THE ON-LINE CALCULATION OF CONDENSER PERFORMANCE AND OPTIMAL CLEANING INTERVAL

Get access (open in a dialog) DOI: 10.1615/IHTC10.4840
pages 207-212

Abstract

The heat transfer community in the U.S. has been actively revising the Heat Exchange Institute and ASME 23 standards for calculating condenser design parameters from specified performance criteria. These standards also form the contractual basis for evaluating the field performance of new condensers during acceptance tests. However, the subsequent calculation of online performance requires a number of additional criteria, especially when the realistic estimation of the cost of losses, and the prediction of the optimal time to clean, are the principal objectives.
This paper discusses an approach to performance analysis, which has been incorporated in several computer programs. One of these has been designed to analyze the data obtained from laboratory tests routinely conducted on tubes removed from condensers in the field. This test data establishes the fundamental behavior of these tubes, both fouled and cleaned, under realistically simulated condensing conditions.
Another program embodies a method for establishing the expected performance of a clean condenser operating under current cooling water and back pressure conditions, based on the fundamental condenser design criteria and the known tube behavior. Using data contained in the thermal kits provided by turbogenerator vendors, a third program incorporates a method for calculating the cost of losses, based on the exhaust flow vs. load and the exhaust enthalpy vs. load relationships abstracted from normal thermal kit data; as well as the measured condenser operating conditions, whether clean or fouled.
Finally, to establish when the condenser should be cleaned, an additional program models the mean hourly cost of losses vs. time, and uses this to predict into the future when the mean cost of losses, including the cost of cleaning, will attain a minimum value.