Optimization of a fluid distributing tube network plays a critical role in the operation efficiency and energy conservation of a cooling system In this paper we analyze the effect of multi-dimension on the structure of a fluid distributing tube network for cooling heat-generating and then seek the optimal fluid structure with minimal pressure drop for a given total volume of the tube network The theoretical results show that the pressure drop of a laminar flow in the tube network reaches the minimum when the cubic value of the parent tube diameter equals to the sum of those of the daughter tube diameter consistent with Murray s law Furthermore it is advantageous to have a higher dimension structure in network arrangement when the number of heat generation units Increases i e network performance improves by adopting a two dimensional and even three-dimensional format as the number of units grows (C) 2010 Elsevier B V All rights reserved