Experimental study on the performance of flat air collector with reticulated endothermic body

Because the flat air collector is simple in structure, reliable in operation, and resistant to cold and frost, it is more suitable for applications such as building heating. This paper presents a flat air collector with a mesh heat sink, and analyzes the effects of air flow, temperature difference between inlet and outlet, and wire mesh density on the heat collection efficiency of the collector. The results show that when the pore density is fixed, the heat collection efficiency increases with the increase of air flow rate, which is 10% higher than that of natural convection when the air flow rate is maximum; when the air flow rate is fixed, the heat collection efficiency increases with the increase of the pore density and the temperature difference between the inlet and outlet, which can be increased by 10% -20%.

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Thermal Evaluation of a Double-Pass Unglazed Solar Air Heater with Perforated Plate and Wire Mesh Layers

Sustainability ◽

10.3390/su12093619 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3619

Author(s):

Afaq Jasim Mahmood

Keyword(s):

Flow Rate ◽

Thermal Efficiency ◽

Air Flow ◽

Wire Mesh ◽

Inlet Temperature ◽

Solar Air Heater ◽

Outlet Temperature ◽

Air Flow Rate ◽

Double Pass ◽

Air Heater

In this study, an experimental outdoor investigation of the thermal efficiency and outlet air temperature was conducted on an unglazed, double-pass, solar air heater with a perforated absorber plate and packing wire mesh layers as a supplemental absorbent area. This was done to observe their effects on the thermal performance of the solar air heater. The double-pass collector was constructed with a bed height of 0.05 m, and a collection area of 1.5 m2. The height of the upper channel was fixed at 0.015 m to improve the thermal efficiency, and the outlet temperature at air flow rates between 0.003 and 0.018 kg/s. The collector was mounted with a slope of 42° facing south, to maximize the intensity of solar irradiance during winter. The effects of the air flow rate, ambient temperature, inlet temperature, outlet temperature, and solar intensity were experimentally investigated. The results showed that thermal efficiency could be improved by increasing the air flow rate, where the highest thermal efficiency achieved was 86% at 0.018 kg/s. However, the temperature difference was increased to a maximum value of 38.6 °C, when the air flow rate was decreased to 0.003 kg/s. Furthermore, the results demonstrated a significant improvement in the thermal efficiency and outlet temperature; and when compared with previous research, the experimental results and the predictions for the outlet temperature using the theoretical model agreed.

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Experimental Study on MPS-HP-II Medium Speed Mills Applied on Unite Using High-Moisture Contained Coal

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.437.388 ◽

2013 ◽

Vol 437 ◽

pp. 388-393

Author(s):

Ke Sun ◽

Shi Qi Jin ◽

Da Chuan Qin

Keyword(s):

Experimental Study ◽

Flow Rate ◽

Power Plants ◽

Air Flow ◽

Load Force ◽

Air Flow Rate ◽

High Moisture ◽

Medium Speed ◽

New Type ◽

Proper Operation

As a new type miller imported from Germany Company Babcock, MPS-HP-II becoming more and more popular because of its outstanding performance in grinding high moisture contained coal. But in daily operation in power plants, the operators encounter with many problems, such as a lack of output, and difficulties in finding proper operation point. In this paper, a we put up with a proper way to calculate the max output of MPS-HP-IImiller, which is demonstrated by experiment. Also we find the optimized working point of MPS-HP-IImiller by analysing the experiment result got by changing the primary air flow rate, separator angel, output and load force.

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