The Optimization Of Heat Transfer And Flow Characteristics Based On Genetic Algorithm

Heat transfer,as one of the most common ways of energy conversion,has the most direct influence on the operation efficiency of both the system and equipments in many engineering applications.Besides,flow past bluff body has been generally investigated due to its universality and the loss ' s important influece on the industrial production caused by it.According to those above,the investigation on the priciples as well as the optimization mechanism of the process of heat transfer and flow is of vital importance for reducing energy loss as well as improving the efficiency of industrial production from the perspective of theory and practice.In the traditional researches,many scholars has obtained more matured results on active or passive methods for heat transfer enhancement or flow drag reduction,which has provided important guidance for practial work.However,above methods has made the optimization process fall into situation,where the optimization procedure could only carry out in a limited scale,thus the optimization process would be strongly limited.So,based on the development of new optimization algorithms,instead of searching the optimal solution in local scale,we actively search for the optimum result in global scope.The heat transfer enhancement based on geometric optimization of conical fin has been investigated.And at the same time,according to the advantages of both the numerical simulation as well as the genetic algorithm,the optimization process of laminar flow past a bluff body based on shape modification with Reynolds number ranging from 100 to 200.Taking heat transfer rate as the objective function,comapred with the optimum results obtained by general genetic algorithm,in this investigation obtaining“stepping” genetic algorithm,the maximum heat trasfer rate could be improved by6.5%,under the circumstance of the same constant basis temperature,the same hight as well as the same basis cross sectional area of the fin.During the process of co-simulation for drag reduction,the self-adaptation optimization process of laminar flow past a bluff body based on the initial state of flow past a circle cylinder hase been investigated.And it has been noticed that thanks to the shape optimization,the shape of the bluff body has changed from circle cylinder to a kind of shape similar to the streamline,which has delayed the separation point of the boundary layer,thus the drag coefficient(drag forces)decreased obviously,and the reduction could be up to 29.3%.Besides,the more ‘smooth' shape has always contributed to the reduction of the lift coefficient,and a slight increase of the Strouhal numbers.