Applications of artificial roughness on the underside of absorber plate in solar air heater duct have been widely used to repair heat transfer with moderate increase of friction factor. The design of the roughness shape and arrangement is very important to optimize the roughened surfaces. The heat transfer and friction features of artificially roughened solar air heaters with different roughness geometries have been reviewed in this article. The article presents the authoritative account of the current progress on topic, discusses the previous developments, and throws light on the future directions. An attempt has been made to comparition the performance of solar air heater having different types of roughness geometries based on correlations proposed in the literature. Thermal efficiency, thermal efficiency improvement factor (TEIF), Thermo-hydraulic efficiency, effective efficiency, and exergetic efficiency performance parameter are evaluated to gauge the performance of different roughness geometries.

In this paper, propose a high speed, low power dissipation, low average power consumption and low PDP (Power Delay Product) based SRAM cell. SRAM cell play an important role in storage devices and hence it is necessary to produce a better design for the optimal use in the portable devices. The MOSFET based conventional 6 T SRAM has high power and delay product with high short channel effects in 32nm technology. Hence, a solution is provided by the use of adiabatic logic and transmission gate logic. In this technique, use a transistor between Vdd and Virtual Vdd to improve the characteristics, it shows that Average power is decreased by 94.75%, delay is improved by 87.15%, power dissipation is improved by 88.78% and energy is decreased by 99.19% in adiabatic proposed circuit when compared to adiabatic FinFET based circuit and similarly the improvements in transmission gate based proposed circuit from simple transmission gate FinFET SRAM is improved by 55.24%, 50.28%, 68.63% and 75% on basis of Average Power, Delay, Power Dissipation and Energy. The proposed circuits are of 8 Transistors.

The renewable energy sources were explored and the solar energy is adjudicating the best option. With abundance of solar energy in many of the poorest parts of the world where access to drinkable water is a challenge, it is reasoned that it is the best and most viable option In this paper, we preheating the water while using the parabolic dish collector and parabolic trough collector. With the use of these, the performance and efficiency were improved. The effect of sun tracking on the design and operating factors such as solar radiation ambient temperature parabolic dish water while using parabolic trough collectors. The was evident from the results that the solar intensity impact on the productivity directly and positively. An arrangement was explored to determine how this affects the performance of the water. In the parabolic trough we use the copper coil to show some significant improvement while preheating the water. So, this arrangement for solar water heating is better for preheating. While using this arrangement a better improvement in water temperature.