Mechanical Engineering

In this study, an attempt has been made to design a new type portable thermoelectric solar still (PTSS). In the PTSS, a thermoelectric module is used to improve the temperature difference between evaporating and condensing zones. Also, a heat-pipe cooling device is used to cool down the hot side of the thermoelectric cooler. To evaluate the performance of the PTSS, the equipment was tested under the climatic condition of Semnan (35° 33′ N, 53° 23′ E), Iran. The experiments were carried out in 5 days. The measurement of solar intensity, wind velocity, ambient temperature, water production, and temperature of other components, for example, thermoelectric module, water, walls and heatpipe was done in the same manner for each day. The results showed that ambient temperature and solar radiation have a direct effect on still performance but there is a reduction in water productivity by increasing the wind speed. The results also showed that temperature of thermoelectric device was lower than that of walls which indicated on the higher production of water.► Using a heatpipe instead of heat sink to cool down the TEC module. ► Higher temperature difference can be achieved by using thermoelectric modules. ► ΔT between water-wall and water-TEC was 9 °C and 34 °C respectively. ► The productivity is increased directly with solar radiation and ambient temperature. ► The wind has an inverse effect on productivity.

In recent years, due to scarcity ofdrinking water, scientists have
conducted many studies to find several optimization methods for
solar desalination systems. Solar stills use clean solar energy
without any noise and any pollution. Therefore, they can be the
best alternative for conventional desalination devices. The
intention of this work is the CFD simulation of two-dimensional
laminar natural convection inside a tubular solar still. In this
manner, the governing equations of mass, momentum, energy
and concentration are solved by a finite volume method.
Furthermore, we investigate the effects of trough geometry,
cover radius, water depth, and position of the trough on the
productivity of the tubular solar still. The results are in a good
agreement with the results of previous reported experimental
data. The results showed that the tubular solar still with circular
trough is the best choice to have a maximum productivity.
Moreover, the best height between the trough and the cover was
found at 124.9mm, and the optimum water-depth and optimum
cover-radius are 48mm and 80 mm, respectively.

In this study, fluid flow and energy separation in a micro-scale Ranque-Hilsch Vortex Tube are numerically investigated. The flow is assumed as 2D, steady, compressible ideal gas, and shearstress-transport was found to be a best choice for modeling of turbulence phenomena. The results are in a good agreement with the experimental results reported in the literature. The results show that fluid flow and energy separation inside the micro-scale vortex tube is quite similar to those of traditional ones. Moreover, it was found that non-dimensional forms of cold-temperature difference and refrigerating capacity are only depend on cold mass fraction. In addition, two correlations have been proposed to estimate non-dimensional forms of cold temperature difference and refrigeration capacity in the micro-scale vortex tube.

The main objective of the present paper is to introduce some features of fake/bogus conferences and some viable approaches to differentiate them from the real ones. These fake/bogus conferences introduce themselves as international conferences, which are multidisciplinary and indexed in major scientific digital libraries. Furthermore, most of the fake/bogus conference holders offer publishing the accepted papers in ISI journals and use other techniques in their advertisement e-mails.