8 Definitions 9 Heat flow. The rate of thermal energy transfer in a medium 10 driven either conductively along a thermal gradient or 11 advectively via mass transport. The standard unit is 12 watts, W. The term is also used to describe a subdiscipline 13 of geophysics, as in the title of this entry. 14 Conductive heat flux. The heat flow per unit area diffusing 15 by conduction along a thermal ...

Thermal rectification is a phenomenon in which thermal transport along a specific axis is dependent upon the sign of the temperature gradient or heat current. This phenomenon offers improved thermal management of electronics as size scales continue to decrease and new technologies emerge by having directions of preferred thermal transport. For most applications where thermally rectifying materi...

Non-isothermal stagnation-point flow with consideration of thermal radiation is studied numerically. A set of partial differential equations that governing the fluid flow and energy is converted into a set of ordinary differential equations which is solved by Runge-Kutta method with shooting algorithm. Dimensionless wall temperature gradient and temperature boundary layer thickness for differen...

The origin of life has previously been modeled by biological heat engines driven by thermal cycling, caused by suspension in convecting water. Here more complex heat engines are invoked to explain the origin of animals in the thermal gradient above a submarine hydrothermal vent. Thermal cycling by a filamentous protein ‘thermotether’ was the result of a temperature-gradient induced relaxation o...

Temperature distribution is a key function for analyzing and optimizing the thermal behavior of various process equipments. Moving bed reactor (MBR) is one of the high-tech process equipment which tries to improve the process performance and its energy consumption by fluidizing solid particles in a base fluid. In the present study, thermal behavior of MBR has been analyzed through mathematical ...

A small salt gradient solar pond with an average surface area of 1.8 m2 and depth of 0.8m has been tested. The depths of storage, gradient and surface zones are 0.3, 0.27 and 0.07m, respectively. The temperature of the storage zone for the summer days reaches its maximum of 65˚ C after about 8 days. Daily variation of the storage zone temperature was about 8˚C which is due to small volume of th...

In this study, thermal radiation was employed for sintering silicon carbide foams that achieved a gradient porous structure. The simultaneous use of graphite and carbon fiber reinforced carbon composite (Cf/C) radiators resulted in an axial temperature gradient of ~600°C along the cylindrical sample, as confirmed by both numerical simulation and experimental measurement. By sintering the cylind...