UNCERTAINTY ANALYSIS OF HEAT-EXCHANGER THERMAL DESIGNS USING THE MONTE-CARLO SIMULATION TECHNIQUE

The Monte Carlo simulation technique for determining uncertainties of the thermal parameters needed in designing heat exchangers is discusse d. Parameters such as the outside diameter D(o), thickness t and therm al conductivity k are assumed to have Gaussian distributions, while th e heat-transfer coefficients h(i) and h(o) are considered to follow no rmal, log-normal and Weibull forms of distribution. An illustrative ex ample is presented. The overall heat-transfer coefficient U obtained f rom the simulation is found to have a distribution that is well approx imated by the Weibull model. Using the Weibull distribution of U, the additional percentage area is calculated for 80 and 99% confidence lev els (CLs). The proposed approach of design analysis incorporates reali stic risks associated with uncertainties of the parameters.