Thermal Behaviour of the Residential Buildings with Cantilever Beam under Winter Day Boundary Conditions

Year 2018, , 155 - 164, 29.06.2018

Lutfu Namli

https://doi.org/10.17350/HJSE19030000090

Abstract

I n this study, the thermal behaviour of residential buildings with cantilever beam under winter boundary conditions was numerically investigated by means of the open-ended structure approach. For this purpose, parametric studies were carried out for various ratios of cantilever beam depth/cantilever beam height d/H and Rayleigh numbers using a computer program for no wind laminar flow conditions. Analyses were conducted for Rayleigh numbers 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 . According to the findings, the mean Nu number along with the outer vertical wall surface L of the residential building, in general, decreases as d/H increases. This decrease in the mean 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.

Keywords

Open-ended structure, Extended boundaries, Cantilever beam, Laminar natural convection

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