We explore the detailed structure of heat release and the energy budget for a freely-propagating lean, premixed hydrogen flame. At lean conditions, the flame is thermodiffusively unstable and spontaneously develops the cellular burning structures, characteristic of this type of flame. The instabilities in the system saturate quickly, resulting in robust, slowly evolving cellular burning feature...

This paper describes recent experiments to investigate the effects that the location of a fire within an enclosure has upon the rate of heat release. A series of pool fire experiments in a 1⁄2 domestic scale compartment using three ventilation geometries (fully open, soffit, and door), and heptane pool fires located in three evenly distributed locations within the compartment (rear, centre and ...

The phenomenon of combustion driven oscillations has long held the interest of scientists and engineers. According to the so-called Rayleigh criterion [1], driving of the pressure oscillations occurs if the periodic heat release rate is generally coincident with the pressure oscillations. The main mechanisms involved are considered to be both thermoacoustic and vortical in nature [2-5]. Useful ...

Experiments were conducted to study the effects of heat release in a planar, gas-phase, reacting mixing layer formed between two free streams, one containing hydrogen in an inert diluent, the other, fluorine in an inert diluent. Sufficiently high concentrations of reactants were utilized to produce adiabatic flame temperature rises of up to 940 K (corresponding to 1240 K absolute). The temperat...

In this study, a reputable Kalina cycle system, KCS 11, is simulated and analysed. Within this efficient cycle, there are three heat exchangers: the first heat exchanger is designated for heat absorption from the heat source, the second heat exchanger is designed for heat release to the cold source, and the third heat exchanger is designed for energy recovery. In order to achieve precise si...

Heat stress occurs when the body cannot release heat and cool itself. When the air temperature is as warm as or warmer than a person's skin, blood brought to the skin's surface cannot efficiently release heat. Working hard in high heat impedes the body's ability to cool itself because the muscles need extra blood, thus decreasing the amount of blood available to circulate to the skin and intern...

It is shown that all heat effects taking place upon annealing of a metallic glass within the glassy and supercooled liquid states, i.e. heat release below the glass transition temperature and heat absorption above it, as well as crystallization-induced heat release, are related to the macroscopic shear elasticity. The underlying physical reason can be understood as relaxation in the system of i...

Abstract—In this numerical study, we want to present the design of highly efficient extruded-type heat sink. The symmetrically arranged extruded-type heat sinks are used instead of a single extruded or swaged-type heat sink. In this parametric study, the maximum temperatures, the base temperatures between heaters, and the heat release rates were investigated with respect to the arrangements of ...