EXTERNAL CONVECTION COEFFICIENTS FOR FRAMED RECTANGULAR ELEMENTS ON BUILDING FACADES

Using data obtained from a heated test plate fixed to the wall of an e ight-storey building, correlations are presented for the external conv ection coefficient h(c), as a function of windspeeds measured at 1 m f rom the test plate surface and at 11 m above the roof (in the free str eam). The effects of a rectangular frame on the value of h(c) are meas ured for a range of frame depths, the geometries tested relating to fa cade configurations which are typical of glazing framework designs com monly found in UK commercial high-rise buildings and atria. For the st ated conditions of use, the regression correlations may be used by des igners and thermal modellers for the prediction of h(c) values for a r ange of typical building facades comprised of mullion and transom-type protrusions. The findings are particularly relevant to improving the accuracy of heat loss calculations from glazing.