## THERMAL SCIENCE

International Scientific Journal

### UNCERTAINTY ANALYSIS FOR EXPERIMENTAL HEAT TRANSFER DATA OBTAINED BY THE WILSON PLOT METHOD: APPLICATION TO CONDENSATION ON HORIZONTAL PLAIN TUBES

**ABSTRACT**

The accurate estimation of convection coefficients constitutes a crucial issue in designing and sizing any type of heat exchange device. The Wilson plot method and its subsequent modifications deliver a suitable procedure to estimate the convection coefficients from the post-processing of experimental data in a multitude of convective heat transfer processes. Uncertainty analysis is a powerful tool not only for handling the data and reporting coherent results of a certain experimental program, but also is a valuable tool in those stages devoted to the experimental design. This paper details the application of an analytical methodology for calculating the uncertainty associated with experimental data obtained by the Wilson plot method. Results based on a representative Wilson plot experiment to measure the condensation coefficients of R-134a over a horizontal 19 mm diameter smooth tube are shown. A parametric analysis was carried out sequentially to investigate the influence of the uncertainties in the measured variables and design parameters of the Wilson plot experiment in the results uncertainties. Although the example presented in this paper relates to a specific heat transfer process, the technique turns out to be rather general and can be extended to any heat transfer problem.

**KEYWORDS**

PAPER SUBMITTED: 2011-07-01

PAPER REVISED: 2011-10-22

PAPER ACCEPTED: 2011-10-26

**THERMAL SCIENCE** YEAR

**2013**, VOLUME

**17**, ISSUE

**Issue 2**, PAGES [471 - 487]

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