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In this paper, heat transfer in a sinusoidal channel filled with nanofluid under magnetic field effect is investigated numerically. The magnetic field transversely applied to the channel. Water as a base fluid and copper as nano particles were considered .The Maxwell-Garnetts model and Brinkman model for heat conduction coefficient and dynamic viscosity were used respectively. The effects of changing some parameters such as shape ,volume fraction , Hartmann number and Reynods number were considered. The results show that increasing in all mentioned parameters lead to increasing in Nusselt number. Volume fraction is mainly affect on maximum local Nusselt number in each channel’s wave while Hartmann number is affected minimum and maximum Nusselt number.

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In present study, impact of single bubble on an inclined wall and its movement are investigated by applying volume of fluid method (VOF) in OpenFOAM open source cfd package using a solver called interFoam. Both phases are incompressible and surface tension between two phases is estimated by CSF method. The effect of some parameters such as contact angle, wall slope and Bond and Morton dimensionless numbers on bubble shapes and velocity are studied. The numerical results show bubble velocity along wall increases with the increase of wall slope angle. The maximum bubble velocity happens at 50 degree. Three bubble regimes are recognized and introduced in this study named as: sliding, bouncing, and zigzagging based on wall slope. The bubble regime changes from sliding to bouncing when wall slope changes from 30 to 40 degrees. In constant Morton number, increment of Bond number increases both velocity and amplitude of fluctuations. In addition, an increment of Morton number in constant Bond number, decreases velocity and amplitude of fluctuations. Moreover, by increment of Morton number, the bubble motion will change from an accelerating motion to a constant velocity condition.