Studies For Heat Conveyance Mechanism And The Application In Heat Transfer Enhancement Due To Chaotic Advection

Along with social economy development, the energy question already seeped to society's each aspect. The energy transformation and the use exist generally in project domains as well as the petroleum, chemical industry, energy, metallurgy, material and the aviation, the electron, the nuclear power and so on the high tech domain. How to reduce the heat exchange equipment the weight, heat exchange equipment volume and the consumption of energy have become the modern hot scientific research domain hot topic. The thermal transmission and the optimization are the energy application key questions which widely exist in each process of energy using.Taking the heat transfer conductance basic physical mechanism as a breakthrough point, the heat transfer conductance key control analysis as the foundation, the residence time distribution (RTD) and non-linear theory as study tools, the kind of tubular flow channel as fundamental research object and the research in the predecessor about the chaotic advection as foundation, the chaotic advection fins based on the new fluid state have been developed. At the same time, the strengthened heat transfer the essence due to the chaotic advection has been promulgated.This article research work includes:Embarking from the energy equation of heat transfer in the convection, analyzing the flow quality of laminar and turbulence respectively, the controlling factors which in these two kind of flowing transfers heat are found out. By establishing the new flowing and heat transfer control model, the energy equation new expression is obtained. This expression points out the key factors influencing heat transfer in the convection and provides the instruction to develop the new strengthened heat transfer method, which have the important fundamental research and the project practical value.The heat conveyance viewpoint shows that in kind of tubular flow channel, the radial flow improvements speed and gradient of temperature relations and the tangential flowing increases thermal the efficiency of loading. These two kinds of flowing are advantageous regarding the heat transfer. Under the condition of constant viscous dissipation, the best heat transfer flow field which causes as a result of the distortion and swinging in the triangle flow channel is obtained.One kind of new fin based on the chaotic advection is proposed. Dynamic analysis on the section of channel shows that this simplified dynamics model conforms to the Duffing equation completely. The flow in the flow channel possibly evolutes to the chaotic advection under the appropriate condition. The flow situation and the hypothesis situation in the channel are similar confirmed through the numerical simulations. The numerical simulations indicate that the simplified dynamics model have the high confidence level.The best flow field hinted by the heat conveyance viewpoint and the chaotic flow field are very similar. In chaotic advection channel, the longitudinal vortexes distribution in the triangle flow channel laminar is congruent the distribution of the best flow field about convection heat transfer. The analysis discovery that this kind flows based on the chaotic longitudinally vortexes is possible obviously to strengthen heat transfer in the laminar of tube and the flow resistance increases very few at the same time. The efficiency indexesη_e is bigger than high may achieve close 200%. The heat transfer enhancement is remarkable stronger than the enhancement of flow resistance.The concept of resident time distribution (RTD) studied in the reactor in the mixer is introduced into the research of heat transfer in chaotic advection integrating mass transfer characteristic. The Pe number's physical meaning is expanded and is pointed out that the Pe number becomes the important symbol parameter to the longitudinal mix and the radial flow in the pipe. The heat conveyance viewpoint promulgates the essence strengthening heat transfer in the chaotic advection. These studies analyses the effect of heat transfer due to the chaotic advection and proposes a method to forecast its.The numerical simulations and experiment studies indicate that the critical Reynolds number transiting from laminar to turbulence will reduce in the complex flow channel of the chaotic advection fins such. Through changing flow channel conditions, such as design parameter, flow regime, medium characteristic, and the different computation models are established. The computed results discover that the velocities are major effect factors for the flowing and the heat transfer in the chaotic advection fins. The dimensionless accurate number relationships of flowing friction coefficient and heat transfer are obtained.This article research content support to develop in the new strengthened heat transfer technology and provide the theory and the experimental in the chaotic flow channels...