Measurement of the heat transfer coefficient for walls

A test set-up was developed for the determination of the external heat transfer coefficient of walls under actual outdoor conditions. The set-up was used to measure the convective heat transfer coefficient for the central region of a vertical wall. Outdoor tests were carried out under a wide range of conditions and the heat transfer coefficient was correlated with wind speed. Results obtained indicate that the heat transfer coefficient varies from 6 to 10 W/m2 • K for wind speeds ranging from 0 to 4 m/s. In addition, the wind direction was found not to have a significant effect on the coefficient for large wall surfaces.