Nanofluid is a new class of heat Transfer fluids engineered by dispersing metallic or non-metallic nanoparticles with a typical size of less than 100 nm in the conventional heat Transfer fluids. This article aims to investigate the overall and convection heat Transfer coefficient and Nusselt number of Al2o3-water nanofluid flowing in a horizontal double pipe heat exchanger under turbulent flow (14000 £Re£ 26500) conditions. Al2o3 nanoparticles with diameter of 20 nm dispersed in Deionized water with volume concentrations of 0.1% £ j £ 0.3% vol. are used as the test fluid. The results show that the overall and convection heat Transfer coefficient and Nusselt number of nanofluid were approximately 15% -21% greater than that of pure fluid. Additionally, the heat Transfer coefficient and Nusselt number increase with an increase in flow rate, Reynolds number, nanoparticle concentration and nanofluid temperature. Finally, the new correlations were proposed for predicting the Nusselt number of the nanofluids, especially. Employing particles of nanometer dimension suspended in solution as nanofluid shows considerable increase in the nanofluid thermal conductivity and heat Transfer coefficient which result in increasing heat Transfer and decreasing operational cost.

Improving the efficiency of Energy consumption in the industrial sector and its sub-sections is important since it can have multifaceted positive effects. First, it reduces production cost at the macro level. Second it helps decrease the volume of needed subsidies. And third, it helps reduce the final cost for industrial products. The three mentioned outcomes of more efficient Energy consumption in turn help enhance the added value of these sectors, increase competitiveness, enhance product quality, reduce import of some key and basic goods and make it possible to increase export of artificially-made products. The present study examines the effects of cutting Energy subsidies on Energy intensity in Iran’s industries. The seasonal time series data approach has been used together with Cobb-Douglas cost function to study the period covering years 2006-2013. The findings showed a negative correlation existed between Energy intensity and Energy prices. Also we found that with technological advancement over time comes a decrease in Energy intensity. Then the Energy prices liberalization scenario was studied for the period covering 2010-2013, assuming a steady rise in nominal prices in the studied period. The findings illustrate that following Energy prices liberalization, Energy intensity is decreased. Indeed, the highest decrease in Energy intensity happens during the first year of liberalization. However, from the second year onwards, the steep decrease in Energy intensity slows.

In this article, the nonlinear vibrations of a simply supported beam with a locally attached bistable nonlinear Energy sink (NES) have been studied. This study focuses on the effects of internal resonance on the dynamic behavior of beams and how vibrations can be controlled by a nonlinear Energy sink (NES). Bistable nonlinear Energy sinks are increasingly utilized due to their higher efficiency compared to monostable nonlinear Energy sinks. A key area of interest in such problems is the forced internal resonances, where the Energy Transferred from the beam to the nonlinear Energy sink is substantial. To address this, the system's equations of motion were derived and made dimensionless, followed by discretization using Galerkin’s method. The method of multiple scales (MMS) was then applied to investigate the 3:1 primary internal resonance. The findings indicate that the frequency response curves are highly sensitive to slight changes in nonlinear Energy sink parameters, particularly damping. However, the nonlinear Energy sink's softening behavior in the frequency domain, as opposed to the beam's behavior, means that physical limitations due to nonlinear Energy sink mass displacement can adversely impact its efficiency. Additionally, the use of NES in beams can significantly improve dynamic stability and extend the service life of structures. The findings of this study can contribute to more optimal design and effective utilization of NES in engineering applications.

The aim is to study nonlinear wave dynamics in solar spicules and jets. The life of jets in the context of Alfven wave dynamics is focused. Here, further insight into the solar atmospheric effects together with initial conditions on the dynamics of Alfven waves along with the characteristic parameters of the spicule or jet itself are provided. Results are based on the theory of magnetohydrodynamics. the location of shock formation by the interplay of the internal and external plasma-beta conditions together with the initial steady flow speeds which are rooted in the initiation location of the solar jet are illustrated. It was known that the plasma-beta of a solar jet affects the shock formation time of torsional Alfven waves. However, its efficiency is shown to be dependent on the external plasma beta conditions. The shock formation time for plasma-beta conditions over unity is directly proportional to the plasma-beta, similar to plasma-beta conditions equal to or below unity. In the case where the plasma-beta inside the magnetic structure is small, the shock formation time is accelerated by increasing the external plasma-beta. In photospheric conditions, as for coronal conditions, the time of shock formation is inversely proportional to the external plasma-beta. When the internal plasma-beta is fixed, for various steady flow speeds, the external plasma-beta accelerates the formation of shocks. These results help us to better understand the role of Alfven waves in solar jets in the Transfer of Energy to the solar system.