Study Of Chemical Heat Sink Of Endothermic Reaction Applied To Heat Dissipation

With the rapid development of high technology such as microelectronics, laser technology, space technology, workplace under environment of high temperature or ultrahigh heat flux would be more common, cooling technologies are also always developing with their progresses, and always provide them basic protection. However, because of the latent heat size restriction of cooling medium phase change, and the harsh demand of space condition, the traditional physical cooling ways gradually cannot satisfy removed requirement of ultrahigh heat flux of these fields, study about the new cooling concept and cooling technology becomes a hot spot.The study of new cooling concepts and new high efficient cooling ways has become one of the supporting technologies for solving the problem of high temperature cooling or high heat flux dissipation. Based on this background, to promote the study of chemical heat sink used in quick cooling of ultrahigh heat flux developing and meet all fields’ needs of highly efficient cooling technologies, a new idea of phase change/chemical combined heat absorbing way has been put forward by predecessors, and in accordance with different reaction temperature range, activated carbon-carbon dioxide hydrate mixture is chose as a kind of cooling media. Carbon dioxide hydrate is prepared by using the batch process method. Thermogravimetric experiment is conducted to measure endothermic enthalpy and reaction characteristics of pure activated carbon and carbon dioxide reaction. Then, Gambit and Fluent simulation software are used to the three-dimensional simulation of carbon-carbon dioxide spray cooling model with high temperature source, and its temperature distribution field and mass fraction distribution field have been obtained, it turns out that the highest temperature is that of the heat source and is just about 1220 K, the upper surface temperature of heat source is about 850 K. Moreover, simulation of carbon-carbon dioxide spray cooling in the two-dimensional model with high temperature source has also been conducted, and its temperature distribution fields and mass fraction distribution fields are also obtained. Simulation results indicate that keeping the CO2 inlet velocity of 0.05 m/s and carbon powder inlet velocity of 0.05 m/s, heat source temperature with reaction happened will be about 500 K lower when relative to that with no reaction happened, and the surface temperature of heat source is only 910.5 K. Through changing the entry-velocities and heat flux densities setting in the process of simulation, the comparison and analysis of different simulation results have been conducted, finally cooling effects of entry-velocity and heat flux density to endothermic reaction chemical heat sink used for high temperature source have been summarized.