This study numerically investigated heat transfer and fluid flow characteristics in a novel cylindrical heat sink with helical minichannels for the laminar flow of fluid with temperature-dependent properties. A finite volume method was employed to obtain the solution of governing equations. The effects of helical angle, channel aspect ratio, and Reynolds number, which were regarded as main para...

The Performance of electric vehicle IGPT Pin fin heat sink can be measured by the temperature field and the fluid pressure and other parameters. In order to improve the cooling effect of Pin fin heat sink, diameter, length and distance of the fin was optimized combination. The relationship between pressure drop of the water inlet, outlet and pin fin parameters was analyzed and calculated. It wa...

To study the anomalous heat effect of Nibased binary-metal-nano-powder samples by gas-phase hydrogen isotope absorption/desorption, three kinds of samples CNZ, CNZ-II and NZ were tested for the temperature range 300-573 K. The highest excess heat power, ca. 2W/g-Ni was obtained with CNZ at 573 K. Peculiar H(D)-isotopic effect and sudden heat sink by abrupt H(D)-desorption were observed. The hea...

In this work, slip flow of helium gas has been studied in a three dimensional rectangular microchannel heat sink with 11 microchannel and 10 rectangular fins. Helium gas flow is considered ideal and incompressible. The finite volume method with using coupled algorithm is employed to carry out the computation. To validate the present work, comparison with numerical and experimental studies is do...

A unique sink orientation (USO) is an orientation of the n-dimensional cube graph (n-cube) such that every face (subcube) has a unique sink. The number of unique sink orientations is nΘ(2 n) [13]. If a cube orientation is not a USO, it contains a pseudo unique sink orientation (PUSO): an orientation of some subcube such that every proper face of it has a unique sink, but the subcube itself hasn...

the aim of this paper is to enhance thermal performance of a microchannel heat sink by using nanoencapsulated phase change material (nepcm) slurry as a cooling fluid instead of pure fluid. a threedimensional model of a circular channel using water slurry of nepcm was developed. the results show a significant reduction in the mean fluid temperature along the channel and heat sink wall temperatu...

the paper numerically presents laminar forced convection of a nanofluid flowing in a duct at microscale. results were compared with both analytical and experimental data and observed good concordance with previous studies available in the literature. influences of brinkman and reynolds number on thermal and hydrodynamic indexes have been investigated. for a given nanofluid, no change in efficie...

The onset of nucleate boiling in the flow of water through a microchannel heat sink was investigated. The microchannels considered were 275 lm wide by 636 lm deep. Onset of nucleate boiling was identified with a high-speed imaging system and the heat flux at incipience was measured under various flow conditions. An analytical model was developed to predict the incipient heat flux as well as the...

The efficiency of the ideal stirling cycle assumes, that the cylinder volumes are isothermal and that the temperatures in the cylinder volumes are identical to the temperatures in the heat sink and the heat source. The efficiency is then identical to the efficiency of the Carnot cycle. However, in a real stirling machine the cylinder volumes are nearly adiabatic instead of isothermal, and the h...

The historical development of thermodynamics follows the industrial revolution in the 19 century, and the advent of heat engines. It is interesting to see how such practical considerations as the efficiency of engines can lead to abstract ideas like entropy. An idealized heat engine works by taking in a certain amount of heat QH , from a heat source (for example a coal fire), converting a porti...