Application And Research About Nonlinear In The Small Electronic Devices Cooling

Nowadays,with the development of the times,miniaturization and integration of the electronic devices was mushrooming.However,the cooling problem played the core factor in influencing its life.This focal point attracted the researchers,and it was also the core problem of this paper.The science of nonlinear was a new interdisciplinary subject along with the rapid development of contemporary science and technology.Nonlinea r,which was means the relationship of two variables,to be further,the relationship was not straight line of course,but was curve line,curve surface or uncertain attributes.Nonlinear was one of the complex and typical characters in the nature.Compared with other characters,it was more close to the objective things.Thus,studying on the value of nonlinear might changed the acknowledge about the tradition as well as deepened the acknowledge about the nature.In this contemporary world,nonlinear existed everywhere,for example,in the change in climate and mathematics,physics,economics,sociology,and music.Besides,when electronic devices worked,the nonlinear existed in airflow caused by the temperature difference,which resulted from the heat uni t.This paper took the electronic devices cooling as the background,under the circumstances of natural convection,models of electronic devices were abstracted as the cavity with different kinds of heat resources.The oscillation and chaos as well as the law of natural convection heat transfer would be studied through the numerical modeling and experimental study.Firstly,FLUNT was used to simulate three kind of cavities,the first one is the cavity heated from below,the second one is the cavity carried one heat source,the third one is the cavity carried two heat sources.The research results can be seen as below.The results suggested that with increasing of Rayleigh number,the airflow in cavity heated from below experienced steady state,single-cycle time state,cycle times state and oscillation,final it would reached chaos state,while the airflow in rectangular cavity with one heat source experienced steady state,single-cycle time state,cycle times state.And the airflow in cavity with two heat sources always stayed in chaos state,intensity of heat transfer related to the airflow.Analyzing the influence of the number of heat source in cavity,we could know that the value of Nusselt number is max in cavity carried no heat source,and it is min in cavity with two heat cavity.When the cavity carried one heat source,the intensity of heat transfer increased along with the length of heat source,but the velocity of heat transfer decreased along with it.On the condition that cavity carried two heat sources,when the difference of temperature was constant,the distance between heat sources increasing,the heat transfer deceasing after increasing;when the distance between heat sources was constant,the heat transfer increasing along with the increasing of the temperature.Through the analysis and comparison of numerical modeling in two-dimension and three-dimension,the conclusion of two-dimension could not take the place of the conclusion of three-dimension.Secondly,laser speckle photography and smoke visualization were used to analyzed the cavity above.Through the comparison of photos,the size of cavity,difference of temperature,distance between the heat sources were the factors which might influence the initial state of vortexes,the vortexes' number and shape,which could explained the cause of chaos.The aspects above were studied,at the same time,the theory of oscillation and chaos were also studied.It could offer some reference value about cooling in electronic devices.