Air-Conditioning (AC) systems are responsible for a considerable portion of the energy consumption in buildings located in high cooling load requiring regions of Iran. In addition, the heat flow through the buildingschr('39') external walls plays a major role in cooling load estimations for the countrychr('39')s hot regions. Therefore, application of insulation materials in external walls has g...

The fracture mechanics examines the development and expansion of cracks in solids and how they affect the deformation of materials. The stress intensity factors at the tip of the crack and the critical stress intensity factors or fracture toughness of materials are considered in the relevant criteria. There are three main modes of applying forces to a crack including the tensile mode, shear mod...

A new model for cooling flows in X-ray clusters, capable of naturally explaining salient features observed, is proposed. The only requirement is that a significant relativistic component, in the form of cosmic rays (CR), be present in the intra-cluster medium and significantly frozen to the thermal gas. Such an addition qualitatively alters the conventional isobaric thermal instability criterio...

Occurrence of Hysteresis like behavior of resistance of Sb 2 Te 3 film in heating-cooling cycle. Abstract Experimental observations of a peculiar behavior observed on heating and cooling Sb 2 Te 3 films at different heating and cooling rate are detailed. The film regained its original resistance, forming a closed loop, on the completion of the heating-cooling cycle which was reproducible for id...

We simulate the effects of viscous dissipation of waves that are generated by AGN activity in clusters of galaxies. We demonstrate that the amount of viscous heating associated with the dissipation of these waves can offset radiative cooling rates in cooling flow clusters of galaxies. This heating mechanism leads to spatially distributed and approximately symmetrical dissipation. The heating wa...

We simulate the effects of viscous dissipation of waves that are generated by AGN activity in clusters of galaxies. We demonstrate that the amount of viscous heating associated with the dissipation of these waves can offset radiative cooling rates in cooling flow clusters of galaxies. This heating mechanism leads to spatially distributed and approximately symmetrical dissipation. The heating wa...

in islamic republic of iran, the heating and cooling of buildings account for approximately 40% of total energy use. from the entire energy loss taking place in a building, one third of that energy loss occurs through the windows. many of today’s existing buildings are not energy efficient, and consume more energy than is needed in order to make the working and living environments comfortable. ...

In this study, the effect off adding SiO2 nanoparticles on the viscosity of base fluid is investigated experimentally. Base fluids are chosen among common heat transfer fluids such as ethylene glycol, transformer oil and water. In addition different volume percentages of ethylene glycol in water are used as ethylene glycol-water solution. In every base fluid different volume fractions of SiO2 n...