Laminate Cooling Structure Of The Internal Flow Resistance And Heat Transfer Characteristics

The resistance and heat ?transfer characters of lamilloy cooling structure were investigated fully with detailed experiments in this paper. In the part of resistance investigation, a great amount of experiment on the elements associated with the resistance character of lamilloy, such as different gas path, pillar height , pillar shape, space between pillars, diameter of hole , thickness of the lamilloy plate , layers of the lamilloy plate ,orient ion of the hole, was finished and two kinds of useful experimental equations on lamilloy resistance character were obtained. The experimental results indicated that the resistance of the lamilloy structure with quadrate pillar is the least, and then the circle and diamond in turn . The resistance of whole lamilloy is mainly affected by the area ratio of the hole in the lamilloy plate, and the bigger the ratio ,the smaller the resistance.The influence of pillar height on resistance is not in monotonous and there must be a height with which the resistance will be the least. The difference of the resistance created in unit length of thickness between single and double-layer iamilioy is very little. In the part of heat-transfer investigation, the distribution of heat-transfer coefficient on lamilloy inner walls were studied carefully. Totally twelve configurations of lamilloy, including different gas path. pillar height and shape of pillar, were studied and all of the lamilloy's heat-transfer character were expressed as a exponential relationship between Nu and Re. The experimental results show that the heat-transfer rates of the lamilloy in which the gas going through a single row of pillar is much stronger than the one in which the gas going through two rows of pillar. As for the lamilloy in which gas going through two rows of pillar, the influence on heat-transfer character due to the change of geometry is very little. In adition, the conclusion can be drawn from the distribution of heat-transfer coefficient that the gas impingement of the jet created by the hole,the reflection of the jet after the impingement and the disturb created by the pillars are the main reasons for the high efficiency of laniilloy cooling.