This paper describes the unsteady and three-dimensional characteristics of heat transfer from a circular cylinder to the cross-flow of air for Reynolds numbers from 120 to 30 000. An infrared camera was used to measure the time-spatial characteristics of heat transfer on the cylinder surface, heated under a condition of constant heat flux. Fluctuating heat transfer was measured using a heat flu...

in this paper by the introduction of the basic equipment of a solar cooling system, solar hydrogen ammonia refrigeration system as a solar cooling technique will be discussed. using heat collector and absorption refrigeration allows us to use residual heat, for cooling, heating and producing hot water and boiling water .this research focuses on methods of heat transfer from the sun into the gen...

Coaxial borehole heat exchangers provide a practical method for geothermal energy extraction, but transfer efficiency is low. In order to address this problem, three coaxial with vortex generators, based on the enhanced theory, are proposed in paper. The author compared and analyzed performance of generators those traditional structures, which explains why new exchanger’s mechanism enhanced. re...

In air-cooling applications with frost production, heat exchanger performance is often air-side limited, because the two-phase flow of the refrigerant provides excellent heat transfer coefficients, and because designers typically use a large air-side fin spacing for frost tolerance. The large fin spacing prolongs operation of the heat exchanger by mitigating the effect of the accumulating frost...

We demonstrate the possibility of achieving enhanced frequency-selective near-field radiative heat transfer between patterned (photonic-crystal) slabs at designable frequencies and separations, exploiting a general numerical approach for computing heat transfer in arbitrary geometries and materials based on the finite-difference time-domain method. Our simulations reveal a tradeoff between sele...