Fuzzy Logic Approach for Controlling Temperature in Electroosmotic Flow Fields

By entering technology to the area of micro and nano scales, the design and fabrication of miniaturized instruments such as microelectronic devices, MEMS, NEMS and ..., become very desirable. Many of these devices deal with flow field in micro- and nano-channels. By decreasing the dimensions of channels, the influence of surface effects becomes prominent and cannot be ignored. One of the most charismatic categories of these phenomena is elecrokinetic effect which can result in electroosmotic flow field (EOF) that has many advantages such as being vibration free, being much more compact, having flat-form velocity and etc. These beneficiaries lead to the increasing stimulus of using this type of flow field. Electroosmosis is defined as the motion of ionized liquid relative to the stationary charged surface by an applied electric field. One of the most important disadvantages of EOF is the Joule heating effect, the generation of heat due to the electroosmosis effect. Besides, micro- and nano-channels are usually used as heat sink in miniaturized devices. By considering these facts, it can be concluded that heat characteristics of EOF must be studied carefully in order to manage and control the Joule heating effect for utilizing the cooling characteristics of micro- and nano-channels. Flow field characteristics can be found by solving Navier-Stocks and Energy equations with proper slip boundary conditions. By considering the partial nature of these equations, many conventional model-based control techniques may not be useful. Therefore, one can suggest some non-model based strategies in order to control the properties of flow fields. In the present study, fuzzy logic controllers will be proposed in order to control the temperature and cooling characteristics of micro- and nano-channel heat sinks.