A green roof can reduce the peak thermal cooling loads and reduce the building energy consumption during the summer. It is also necessary to understand the thermal performance of these green roof assemblies during the winter when affected by an accumulation of snow on the rooftops. This study presents an experimental investigation and discusses the snow influence on the heat transfer processes ...

A numerical finite difference study has been earned out for two dimensional radiation-natural convection interaction phenomena in a vertical circular pin located at a non-participating (i.e. transparent) fluid. The coupled conservation equations in boundary layer (continuity, momentum, and energy equations) and pin energy equation are solved simultaneously using modified box method and fully im...

In this study, the thermal performance of three kinds of roofs with different heat capacity and thermal conductivity under different external conditions has been investigated using a numerical method. For this purpose, the combined solar radiation, conduction and convection heat transfer were calculated implicitly in terms of a one-dimensional finite difference method. Different high and low so...

characteristics of efficient roof shape is a part of configuration of efficient architecture which seems to be an ideal in contemporary architecture especially in contemporary architecture of developing countries such as iran. this study is to investigate two roof shapes in view of air flow and indoor-temperature to find efficient roofs shapes for residential buildings in tehran. computational ...

The heat transfer for a non-Newtonian power-law fluid over a moving surface is investigated by applying a uniform suction/injection velocity profile. The flow is influenced by internal heat generation/absorption. The energy equation is solved at constant surface temperature condition. The Merk-Chao series is applied to obtain a set of ODEs instead of a complicated PDE. The converted ordinary diffe...

Heat transfer coefficient in nucleate pool boiling near critical heat flux at least one orderhigher than the convectional heat transfer modes. In this paper, an experimental setup isdesigned and fabricated to investigate the mechanism of heat transfer from boiling surface tobulk liquid near critical heat flux. The images of pool boiling near the high heat flux regionreveals that the individual ...

In this work, a multi-objective optimization on novel insulated roof with solar water heating system at low material cost has been carried out through Taguchi based grey relational analysis technique. The novel roofs have concrete, insulating polyurethane, and a channel of water in a metallic pipe tunneling the chromium block. Chromium block is used to conduct more heat to raise the water to re...

The interaction of thermal radiation with conduction and laminar natural convection in a vertical circular pin, situated at participating gas, is numerically investigated. An absorbing and emitting gas is considered, and treated to be a gray participating media. Under the idealizing of gray gas, the Rosselan4 approximation is employed to describe the radiative heat flux in the energy equation. ...