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There are large amount of small packages filled with heat generated components in aerospace industry or electronic and information industry.Because of the limited space, the generated heat current cannot be washed away by a stream of coolant (convection), and the most effective ways to channel the generated heat out of the electronic package is by conduction.The so-called volume-to-point flow problem suggested by Bejan is related to this problem: consider a finite-size volume in which heat is being generated at every point and which is cooled through a small patch (heat sink) located on its boundary, and a finite amount of high conductivity material is available.Based on the essential similarity between heat current in heat transfer problem and material current in nature, the growth mechanism of organism branching system in nature is studied and a new design method of optimal layout of heat transfer paths is suggested.The thermal conductivity of each element is selected to be design variable and minimizing the maximum temperature of the design area is the objective.By analyzing temperature gradients of elements, the material with high thermal conductivity is gradually distributed on the design area.As a result, optimal layouts of heat transfer paths are obtained.Several typical examples with different thermal boundary conditions are studied to validate the effectiveness of the suggested method.Comparing with the results of current methods, the optimal layouts of heat transfer paths with nature current mechanism can achieve temperature uniform and conduct heat effectively.Furthermore, the engineering application of the heat pipe layout problem in the satellite is studied by this method.Different from volume-to-point flow problem, heat pipe layout problem come down to that a finite-size volume in which heat is being generated at some special points and which is cooled through the whole area radiation.Considering different heat source conditions in the models, heat pipe layouts plans are given.Compared with traditional heat pipe layout, the temperature of the design area after optimal design is more uniform.Taking the practical applicability into account, optimal layout plans are rectified and regulated further.The design results show that the suggested method based on nature current mechanism has more extensive range of applications in different heat conductivity materials and diverse thermal boundary conditions.