The forced convection heat transfer in high porosity metal-foam filled tube heat exchangers are studied in this paper. The Brinkman Darcy momentum model and two energy equations for both solid and fluid phases in porous media are employed .The study shows that using metal-foams can significantly improve the heat transfer in heat exchangers. Keywords—metal foam, Nusselt number, heat exchanger, h...

Infrared thermography was used to measure heat transfer by radiation and the surface temperature of starlings (Sturnus vulgaris) (N=4) flying in a wind tunnel at 6-14 m s-1 and at 15-25 degrees C. Heat transfer by forced convection was calculated from bird surface temperature and biophysical modelling of convective heat transfer coefficients. The legs, head and ventral brachial areas (under the...

A numerical study is carried out to investigate the laminar forced convection heat transfer from a circular cylinder. The fluid is assumed to be incompressible, the Reynolds number ranged from 0.1 to 1000, and the Prandtl number was equal to 0.7. The range of study includes heat transfer in creeping flow (Re40). The equations were discretized by a control-volume-based finite difference techniqu...

Several researches dealing with the single-phase forced convection heat transfer inside micro channels have been published in the past decades. The performance of liquid flow has been proved that agree with the conventional correlations very well (Yang and Lin [2007]). However, owing to the low heat transfer coefficient of gaseous flow, it is more difficult to eliminate the effects of thermal s...

This research focuses on the need for preserving fruits in rural areas to prevent waste. The solar drier is made of vital chambers i.e. the concentrator chamber (that harvests the solar irradiance), the transport pipe (that transports the heat generated by convection) and hanger chamber (where the fruits are placed). The temperature within the concentrator chamber and hanger chamber was monitor...

A numerical investigation has been carried out for mixed convection flow in a rectangularventilated cavity with a heat conducting solid circular cylinder at the center. Forced convection flowconditions were imposed by providing an inlet at the bottom of the left wall and an outlet vent at the topto the other sidewall. In this paper, the effect of cavity aspect ratio as well as the mixed convect...

A theoretical study is presented in this paper to investigate the conjugate heat transfer across a vertical ®nite wall separating two forced and free convection ̄ows at different temperatures. It is assumed that the heat conduction in the wall is only in the transversal direction. We also assume that countercurrent boundary layers are formed on the both sides of the wall. The governing equation...

Heat and vapour convective surface coefficients are required in practically all heat and vapour transport calculations. In building envelope research, such coefficients are often assumed constants for a set of conditions. Heat transfer surface coefficients are often determined using empirical correlations based on measurements of different geometry and flows. Vapour transfer surface coefficient...