Thermal Behaviour of Residential Buildings with Cantilever Beams under Winter Boundary Conditions

In this study, the thermal behaviour of residential buildings with cantilever beam underwinter boundary conditions was numerically investigated by means of the open-endedstructure approach. For this purpose, parametric studies were carried out for various ratiosof cantilever beam depth/cantilever beam height (d/H) and Rayleigh numbers using a computerprogram for no wind laminar flow conditions. Analyses were conducted for Rayleighnumbers in the range of 103 to 106. The calculations were carried out for the ratios of d/H,namely 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0. The working fluid was treated as air (Pr=0.71). Accordingto the findings, the mean Nu number along with the outer vertical wall (surfaceL) of the residential building, in general, decreases as d/H increases. This decrease in themean Nu number is evident for Ra≤104, but it appears to be more pronounced after Ra=105.To have minimum heat loss from a residential building under winter day boundary conditions,it is suggested that the ratio of d/H should be between 0.2 and 0.5.

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