In this article, turbulent flow heat transfer in the air gap between rotor and stator of a generator under nonhomogeneous heat flux is studied experimentally. The rotor consists of four symmetrical triangular grooves. The stator surface is smooth and does not include any grooves. The relative heat flux between the rotor and the stator is 1 to 3. Temperature and heat flux are measured locally at...

This paper presents the exergy analysis of a desalination unit using humidification-dehumidification process. Here, this unit is considered as a thermal system with three main components, which are the heating unit by using a solar collector, the evaporator or the humidifier, and the condenser or the dehumidifier. In these components the exergy is a measure of the quality or grade of energy and...

Energy and exergy concepts come from thermodynamics laws and are applicable to all fields of science and engineering. This study considers numerical simulations of combustion of hydrogen with air in a constant pressure environment and exergy terms according to first and second laws analysis using homemade code. Chemical kinetic model includes 20 reactions and 9 species.  At the first stage of p...

In the coming decades, global warming and increase in temperature, in different regions of the world, may change indoor and outdoor thermal comfort conditions and human health. The aim of this research was to study the effects of global warming on thermal comfort conditions in indoor ambiences in Iran. To study the increase in temperature, model for assessment of greenhouse-gas induced climate ...

rhabditidae is a family of free-living nematodes. free living nematodes due to their active movement and resistance to chlorination, do not remove in conventional water treatment processes thus can be entered to distribution systems and cause adverse health effects. ultraviolet radiation (uv) can be used as a method of inactivating for these organisms. this cross sectional study was done to inv...

The effect of soil warming on CO2 and CH4 flux from a spruce–fir forest soil was evaluated at the Howland Integrated Forest Study site in Maine, USA from 1993 to 1995. Elevated soil temperatures (~5 °C) were maintained during the snow-free season (May – November) in replicated 15 3 15-m plots using electric cables buried 1–2 cm below the soil surface; replicated unheated plots served as the con...

This paper presents the results of a numerical study on the heat transfer performance and the removal process of fluid particles under the influence of magnetohydrodynamic mixed convection in a horizontal channel with an open cavity. The bottom wall of the cavity is heated at a constant temperature (Th) while the top wall of the channel is maintained at a relatively low temperature (Tc). Air wi...

The effect of vertical air temperature gradient on overall and local thermal comfort at different overall thermal sensations and room air temperatures (at 0.6m height) was investigated in a room served by displacement ventilation system. Sixty tropically acclimatized subjects performed sedentary office work for a period of 3 h during each session of the experiment. Nominal vertical air temperat...

abstract     evapotranspiration and plant water absorption reduce when exposed to water stress and this reduction results in an increase in leaf temperature. to determine the effect of water stress on leaf temperature and timing of irrigation using leaf temperature, a research was conducted on the research and education greenhouse production center of islamic azad university, isfahan branch (kh...

Effect of air cushion layer right before impact of a rigid body onto water surface has been investigated in this paper. The study is mainly focused on evaluation of cushioning pressure and the resulting free surface elevation. The air flow is assumed to be an irrotational flow which is governed by Laplace equation. The air problem and the resulting response of the water free surface are suppose...