The role of confinement on the flow of power‐law fluids past a cylinder confined symmetrically between two parallel walls has been investigated numerically over wide ranges of conditions as follows: power‐law index (0.4 ≤ n ≤ 1.8), Reynolds number (40 ≤ Re ≤ 140) and blockage ratio (2,4,6). For Newtonian fluids, moderate degree of confinement stabilizes the flow thereby delaying the onset of the laminar vortex shedding regime. Although similar stabilization also occurs in shear‐thickening fluids, this relationship is complex for shear‐thinning fluids. Depending upon the degree of shear‐thinning, the walls may stabilize or destabilize the flow. Extensive results are presented on streamline, vorticity contours and pressure profiles herein. The power‐law behavior exerts significant influence on the macroscopic momentum transfer characteristics also. Thus, the drag and lift coefficients and Strouhal number exhibit complex dependence on Reynolds number, blockage ratio and power‐law index. Finally, the present results are consistent with the limited data available in the literature. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

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The development of a remote-access real-time laboratory (RART-Lab) is described, and a case study is presented of its application to a real-time mechanical engineering experiment, namely a study of thermo-hydrodynamics of fl ow through mini-channels. (The study of such fl ows is vital for many applications, ranging from electronics thermal management to fuel cells.) The RART-Lab concept encompasses data acquisition during the experiment, storage, post-processing and online transmission of data to multiple users logged on to their respective web browsers. Control of the experimental process parameters (e.g. liquid mass fl ow rate and heater power level) from one (or more) remote stations over the web in real time is also incorporated. Online video images of the experimental facility, visualization modules and color-indexed temperature data can be transmitted by webcam. The system developed has a friendly graphical user interface. It also allows transmission of process parameter alarm signals via an e-mail client server or via an SMS text message to a mobile telephone. Simultaneously, conventional chatting has also been incorporated to add vibrancy to inter-user communication. In addition, three-dimensional computational fl uid dynamics simulations have also been done simultaneously with the real-time laboratory to mimic the experiments. Such an integrated development greatly widens the possibilities of collaborative research, development, simulation and experimentation, to overcome the need for the physical proximity of the experimental hardware and experimenters. Such generic tools not only make academic interactions and real-time data sharing more fruitful but also greatly facilitate joint research and development activities between academia and the industrial community.

In the present situation, there is a need for devices to carry the thermal energy generated in the system. Fins are the efficient devices which are going to carry the heat generated in the system. In the present work, we have chosen a special shape of fins by choosing two different materials. Toroidal fins have been considered. By varying its shapes heat transfer analysis has been carried out. In the present work, we have considered the toroidal fins having Aluminium and Gunmetal materials. The thicknesses of the spline are reduced from 7 mm to 3mm. The effectiveness for Aluminium 3mm is 3.28 and for 7mm is 3.3723. The effectiveness of Gun metal 3mm is 2.02 and for 7mm is 2.7895.