the steady state effect of vertical fins is assessed on a photovoltaic/thermal solar air heater having a double pass configuration in which fins are placed in the lower channel perpendicular to the direction ofair flow. air passes through the upper channel of the air heater and before passing in the opposite direction through the lower channel. the effects of design, climatic and operating para...

The reoxidation rate of sponge iron pellets and briquettes and oxidation of pure iron powder with compressibility between 27% and 55% in air and within the temperature range 300-900°C has been investigated. Factors affecting the oxidation rate are presented. These include the effect of temperature, compressibility, and sintering of Fe-powder before and during the oxidation.

a succession of late campanian- early maastrichtian is analyzed from gurpi formation with regard to the calcareous nannofossils. correlation matrix was applied for the first time to the entire nannofossil assemblage to reconstruct environmental conditions. a detailed quantitative calcareous nannofossil analyses is performed on samples in order to further investigate the climate events, and inte...

in this study, shelf life properties of tomato powder under effect of air drying temperature were studied. the qualitative determination was observed that acceptance of color, aroma,flavor, and appearance at 70oc is better, so best temperature was 70oc for producing of tomato powder. tomato powder after drying ,were stored into three kind of packaging including thin cellophane, thick cellophane...

Abstract—In this study, we experiment on precise control outlet temperature of water from the water cooler with hot-gas bypass method based on PI control logic for machine tool. Recently, technical trend for machine tools is focused on enhancement of speed and accuracy. High speedy processing causes thermal and structural deformation of objects from the machine tools. Water cooler has to be app...

The operation of air-cooled chillers accounts for significant energy consumption in local commercial buildings, and low operational efficiency especially under partial load conditions and poor control are part of reasons for such huge energy consumption. Chiller efficiency can be improved by enhancing heat transfer rate in condensers. This paper considers how the chiller performance can be impr...

radiation input from the sun is the source of energy for the earth’s climate system (hartmann, 1994). most of the solar radiation absorbed at the surface, the rest is absorbed by the atmosphere. the global temperature profile of the atmosphere reflects a balance between the radiative, convective, and dynamical heating/cooling of the surface-atmosphere system. understanding of the climate change...

Substantial amounts of dead wood in the intertidal zone of mature mangrove forests are tunnelled by teredinid bivalves. When the tunnels are exposed, animals are able to use tunnels as refuges. In this study, the effect of teredinid tunnelling upon mangrove forest faunal diversity was investigated. Mangrove forests exposed to long emersion times had fewer teredinid tunnels in wood and wood not ...

Cement manufacturing requires cooling down of hot clinker at temperature about 1350o C to lower than 100 o in a system known as cooler. Many plants are unable cool the below 250o C. This challenge led scaling actual cooler test rig size ratio 25:1 suitable for simulation. Computational Fluid Dynamics (CFD) tools (Solid-Works and ANSYS) were used achieve The outlet temperatures obtained from sim...