outdoor experiments on a once-through single glazed solar air heater with perforated metal absorber plate were conducted to determine the practical effect of absorber plate porosity as well as suction air flow rate on the collector thermal efficiency and its total pressure drop. three aluminum absorber plates were made perforated by drilling circular holes with different diameter/pitch ratios i...

in this study thin layer drying of corn in a convective dryer was investigated at air temperatures of 50, 60 and 70ºc and air flow rates of 1, 1.4 and 1.8 kg min-1. experiments were performed in completely randomized design (crd). the effect of air temperature and flow rate on drying time, drying rate, effective diffusivity coefficient and activation energy were studied. results showed that the...

In the most application of nozzle with gas-liquid two-phase flow, the quality of mixture in exhaust of nozzle is the most important parameter as well as the flow velocity. On the other hand, in some industrial application, such as water injection in forced induction (turbocharged or supercharged) internal combustion engine the spray quality is the main goal of designing. In this case and for im...

Heat transfer from the internal surfaces of a vertical pipe to the adjacent air gives rise to the air flow establishment within the pipe. With the aim of optimizing the convective air flow rate in a vertical pipe, the details of the flow and thermal fields were investigated in the present study. Conservation equations of mass, momentum, and energy were solved numerically using simple implicit f...

in the present study a quasi 2-d numerical model is developed for calculating air concentration distribution in rapid flows. the model solves air continuity equation (convection diffusion equation) in the whole flow domain. this solution is then coupled with calculations of the free surface in which air content in the flow is also considered. to verify the model, its results are compared with a...

a mixed solar dryer with a specific mechanism to vary the tilted angle of collector, is utilized to fulfill all tests. the efficiency of the dryers is low because of various reasons such as heat loss of air in an open flow circuit. getting air back toward the air inlet of dryer can increase the efficiency of dryer and decrease drying process period. a new mechanism considered for dryer which co...

Diesel-operated Load Haul Dumper (LHD) vehicles are commonly used in underground coal mines. Despite their value as utility vehicles, the main drawback of these vehicles is that they generate diesel particulate matter (DPM), a known carcinogenic agent. In this work, an attempt is made to model DPM flows generated by LHDs in an underground coal mine environment for different DPM flow and intake ...

flow regime in dam's bottom outlet is divided in pressurized flow and free surface flow by the gate located for discharge control. down stream tunnel involves high velocity multi component air –water flow studied by mathematical model. in this research work, we used finite volume mixture two phase flow model. because of high reynolds number, standard two equations k-e turbulence model was ...

The shape of the air flow in the interior is heavily influenced by the air distribution system and the way air enters and exits. By numerically simulating flow by computational fluid dynamics, one can determine the flow pattern and temperature distribution and, with the help of the results, provide an optimal design of the air conditioning system. In this study, a chamber was first constructed ...