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Solar air heater represents one of the substantial thermal systems that is utilized for collecting the heat of the solar radiation to be used for space air heating and farming products drying. This study aims to investigate the thermal performance of the solar air heater (SAH) with a multiple air pass using different arrangements of the corrugated absorber plate with a metal mesh and phase change material (PCM) as a thermal storage system experimentally. The test rig of SAH was consisted of an external insulated container, absorber corrugated plate, double glass sheets, air fan, and measuring devices. A black-coated corrugated Aluminum sheet of 900 mm in length, 500 mm in width, and thickness of 1 mm was installed inside the SAH container as absorber plate and supplied with 20 kg of Paraffin wax as PCM for thermal storage. Four cases of the SAH with a corrugated absorber plate at different arrangements are evaluated experimentally in April 2022 under Baghdad city climatic conditions to investigate optimal thermal performance of the SAH. Double pass and triple pass air flow SAH are examined in the first and second cases respectively. While a triple pass with a metal mesh and PCM assisted absorber plate are tested in the third and fourth cases respectively. The results revealed that the enhancement in the SAH outlet air temperature for case 4 was 21% compared with other test cases during low solar radiation hours. A relatively low air flowrate of 0.0095 kg/s has reflected a higher outlet air temperature by about 12 % compared with the other air flowrates 0.012 and 0.0134 kg/s considered in this work. Higher thermal efficiency for the solar air heater was 74, 73, 71.6, and 70% for cases 3, 2, 1, and 4 respectively at peak solar radiation hours, while at low solar radiation period, case 4 reflected a higher efficiency by about 15% compared with other test cases. [ABSTRACT FROM AUTHOR]

In this study, the results of evaluating various mesh types used to reinforce ferrocement panels are discussed. The study's primary goal was to choose the most appropriate mesh for further work after examining the effects of various mesh types used as reinforcement in thin mortar specimens. Mesh with a 1.58 mm diameter includes welded mesh, galvanised woven mesh, and expanded metal mesh. The apertures have measurements of 10x10, 15x15, and 20x35 millimetres. Mesh with a 1.58 mm diameter includes welded mesh, galvanised woven mesh, and expanded metal mesh. The apertures have measurements of 20x35mm, 10x10mm, and 15x15mm. Wire mesh was used in three levels to reinforce panels that were 560x150x35mm in dimension. The walls were made using mortar utilising a 1:2 blend ratio and a 0.40 water to cement ratio. After a time of curing, the Using a four-point loading method, four specimens were tested on a universal testing machine. [ABSTRACT FROM AUTHOR]

The paper is about intensification and energy saving in the separation processes of liquid mixtures. Authors consider the implementation of thermal rectification in heat-mass exchange apparatuses using internal condensers. A new contact device with inclined plates and internal pipes was developed. The research aimed to determine the hydraulic resistance of the designed contact device under various heat-and-mass transfer apparatus operating regimes. Two series of experiments in the heat-mass exchange apparatus with developed contact devices were conducted with and without the advanced contact surface in the form of a mesh metal grid. The dependences of pressure drop for wet/dry contact devices with inclined plates and internal pipes at different wetting rates were plotted. The presented dependencies make it possible to consider changes in the physicochemical properties of working fluids at various pressures and temperatures. [ABSTRACT FROM AUTHOR]

This paper presents the theoretical parametric analysis of double flow solar air heater having expanded metal mesh as artificial roughness on the absorber plate. The effect of the fraction of mass flow rate (r) in the upper and lower flow channels of a double flow roughened solar air heater having expanded metal Expended surface applied on the absorber plate is the most efficient method to improve thermal performance of solar air heaters. In the present work, an analytical approach has been made to investigate the thermal performance of a solar air heater having expended surfaces for enhancement in the coefficient of heat transfer. The objective of this paper is to analyze the thermal performance parameters against varying mass flow rates. The results obtained shows that the thermal efficiency increases with the increase in surface area within limit. The collector efficiency factor, thermal efficiency, change in temperature and useful heat gain at same mass flow rate (0.055kg/sec.) are increased by 7%, 4%, 4% and 30 W/m2 respectively. [ABSTRACT FROM AUTHOR]

This paper explains the evaluation of erosion profiles in metal mesh supported SCR plate catalyst structures in which the glass fibers concentration in the catalyst material is considered as prime factor for erosion resistance and mechanical strength. The samples are prepared and tested at the specified and constant conditions like velocity as 30m/s, sand flow rate as 2g/min, average particle diameter 300 µm and all these samples were tested at different angles at impact preferably 15°,30°,45°,60°,75°,and 90° as per ASTM G76 standards. Say, if 5% glass fibers are present in catalyst material, then erosion resistance increases, but the density of glass fibers is very less because each glass fiber is approximately 20 microns in diameter and weight of individual is negligible. The composition in which 2% fiber is present has slightly higher erosion comparatively, but 3% glass fibers or more foreign inclusion like excessive binders can be eliminated that contributes much for the conversion of NOx. So 2% -3% glass fibers are preferred and optimized based on NOx conversion and erosion resistance property. [ABSTRACT FROM AUTHOR]