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In the present study, a detailed numerical simulations of liquid flow in microchannel heat sink with four different geometry of ribs: rectangular (RR), backward triangular (BTR), forward triangular (FTR) and diamond (DR) arranged symmetrically inside reentrant fan shaped cavities (FC) on side walls has been conducted and compared with smooth channel (SC) to acquire fluid flow and heat transfer characteristics between Reynolds numbers of 136−588. The local pressure, temperature and heat transfer coefficients were determined to understand the convective heat transfer regimes and to analyze local flow behavior. The three-dimensional conjugate heat transfer model, investigation is done extensively to identify the influence of geometrical parameters towards augmenting thermal performance with parametric optimization. Evolved governing equations are solved by using SIMPLEC algorithm. Attempt has been made to improve heat extraction ability with reasonable pressure drop by replacing the existing simple design of microsink. It is observed that Nusselt number and friction factor are in good agreement with previous experimental data. Based on detailed parametric study, it was found that FC-RR is good in achieving maximum Nusselt number, but due to higher pressure drop penalty giving lower performance. Out of four proposed, FC-DR is conferring upstanding balance between heat transfer, pressure drop and giving the best thermal performance of 1.97 at Re = 391.47.

The role of viscosity coefficient (η ′ ), coulomb coupling parameter (Γ) and dust mass on the growth of jeans mode is investigated in strongly coupled dusty plasma using equations of Generalized Hydrodynamics (GH) Model. The novel aspect of this work is that the force arising due to electrostatic pressure caused by grain grain interaction has been included in the dynamics of dust particles. This force is found to play a significant role in counter balancing the self gravity effect, thereby reducing the growth rate of jeans instability. The present work may provide more physical insight in understanding the mechanisms behind formation of planetesimals, stars etc.

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Aluminium (Al) and copper (Cu) are widely employed in the industry due to their significant corrosion resistance and electrical conductive properties. The simultaneous requirement of different special properties has increased the trend of joining of Al and Cu. The joining of dissimilar materials has arisen as a new challenge in the research field in the past decade. Friction stir welding (FSW) is a very worthy process to join metals that aren't the same. This article delves into the intricacies of FSW to join compatible metals such as Al and Cu. The various parameters of FSW, namely tool design, tool pin offset, rotation speed, welding speed, tilt angle, and different types of welding joints, are highlighted in this article. It also goes through the different types of defects, microstructures, and intermetallic compounds (IMCs) that are formed during Al-Cu FSW. The electrical behavior and corrosion behavior of the weld zone in Al-Cu FSWed joints were also reviewed. Role of interlayer in some emphasis was also given to form effective joints.