Heat transfer in the microchannels with fan-shaped reentrant cavities and different ribs based on field synergy principle and entropy generation analysis

Analysis of field synergy principle and the relationship between secondary flow and heat transfer in double-layered microchannels with cavities and ribs

“…Such as, helical ducts [12], a tube dundle of a preheater [13], a channel with longitudinal vortex generator [14], heat exchannger [15], et al In our pervious works, we fisrtly used this pinicple to investigate the essence of heat transfer enhancement in single-layered microchannels [16]. As mentioned above, this is the further work based on our previous works [16,17]. Firstly, two types of double-layered microchannels with different arrangement of cativities and ribs are presented.…”

Characteristics of entropy generation and heat transfer in double-layered micro heat sinks with complex structure

“…The order of heat transfer in different surfaces is analyzed as follows: the axial thermal diffusion of the inlet and outlet surfaces can be neglected if Peclet number greater than 100 [21]. Pelect number is the product of Reynolds number and Prandtl number.…”

“…(21). Here, T f1 and T f2 are the average temperature of fluid in the first and second layer respectively, i.e., transfer and flow fraction.…”

“…Zhai et al [21] and Xia et al [22] pointed out that the combined effect of cavities and ribs in microchannels caused better thermal performance when compared with rectangular microchannels, due to the growth of thermal boundary layer and the increase of flow turbulence. Hajmohammadi et al [23] proposed some simple types of cavities intruded in the rectangular and trapezoidal body.…”

Heat transfer enhancement of Al2O3-H2O nanofluids flowing through a micro heat sink with complex structure

“…The characteristic of deionized water flowing through micro heat sinks with complex structure has been reviewed by Xu et al [2], Zhai et al [3], Foong et al [4] and other authors. Xia et al [5] numerically investigated the characteristic of flow and heat transfer in microchannels with cavities and ribs.…”