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This paper aims to present a comparative study of a solar dryer with and without multiple phase change materials (PCMs). It also involves designing and fabricating the experimental model of an indirect solar dryer which uses PCMs for thermal energy storage.

A corrugated aluminium sheet is used as an absorber plate. Aluminium pipes of 0.75 inch are welded under the corrugated sheet to store the PCM. Here, multiple PCMs are used – one with a high melting point and the other with a low melting point for the purpose of improving efficiency. A single air pass model in which air moves over the absorber plate is used for the study. Air is heated in an air heater section which also contains thermal energy storage. The energy obtained in the air heater section is first used to heat and melt the PCM.

Thus, heat energy is stored into the PCM and then the heated air moves into the drying chamber in which drying take place. When the sun’s insolation reduces, discharging from the PCM takes place. Thus, it reduces the fluctuation in the energy and provides continuous energy to the system. Glass wool is used as an insulation material. Different parameters for this air heater-dryer have been calculated.

The current study enhances the understanding of solar drying process and the developed model with and without multiple phase change materials can be used for optimising the drying process.

The catastrophic failures of these thick-wall cylinders are mainly due to the presence of inherent cracks in the material. The present study aims to deal with the analysis of stress for a given range of inside pressure. The paper deals with the calculation of radial and tangential stresses for various external pressure-to-internal pressure ratios and external radius to internal radius of the thick-walled cylinder.

The inlet line to the combustion chamber normally has an internal diameter of 150 mm and has a thickness of 25 mm. Normal temperature of the working fluid is about 80°C and the outside temperature is kept as room temperature. The present work deals with the stress analysis of the inlet line with and without internal crack. Also the stress intensity factors are calculated to check with the fracture toughness. Analysis is done both theoretically and by FEM by using the well-known software ANSYS.

Results show that the radial stress is independent of the external radius-to-internal radius ratio, while the tangential stress increases.

In process industries like nuclear or chemical, etc., structures in the form of thick-walled cylinders play a vital role, as its failure can affect humans and the environment. Because of this, the design and analysis of the above cylinders are of much significance.

Due to constant or cyclic operating pressure of pressure vessels and its corresponding pipelines usually in the form of thick-walled cylinders, reliability of the materials and structures used is of critical importance, as its failure can be deadly and possess lethal dangers when the cylinder contains flammable, toxic or reactive working fluid. The major ruling factors for the failure are none other than stress-related defects and presence of cracks.

This paper aims to present a comparative study of the wear properties of ferrous welded materials like EN8, EN9 and mild steel (MS).

The material is cut into specific dimension after hardfacing and is studied for the wear properties of the material. The wear testing is done on a pin-on-disc apparatus. The microhardness of the material is studied using the Vickers microhardness measuring apparatus.

The wear properties of ferrous welded materials like EN8, EN9 and MS are studied. It is found the MS has the least wear when compared to EN8 and EN9. The microhardness of MS is higher than EN8 and EN9, thus making it more wear-resistant than EN8 and EN9. The coefficient of friction in the dry sliding condition is found to be constant throughout the experiment.

Major restriction is the amount of time required for use-wear analysis and replication experiments that are necessary to produce reliable results. These limitations mean that the analysis of total assemblages with the intention of producing specific results, especially of worked materials, is not feasible.

Generally, the complexity and rigour of the analysis depend primarily on the engineering needs and secondarily on the wear situation. It has been the author’s experience that simple and basic wear analyses, conducted in the proper manner, are often adequate in many engineering situations. Integral and fundamental to the wear analysis approach is the treatment of wear and wear behaviour as a system property. As a consequence, wear analysis is not limited to the evaluation of the effects of materials on wear behaviour. Wear analysis often enables the identification of nonmaterial solutions or nonmaterial elements in a solution to wear problems. For example, changes in or recommendations for contact geometry, roughness, tolerance and so on are often the results of a wear analysis.

The value of the work lies in the utility of the results obtained to researchers and users of the EN8, EN9 and EN24 material for their components.

The purpose of this paper is to understand the effect of basin water depth towards the cumulative distillate yield of the traditional and developed single basin double slope solar still (DSSS).

Modified single basin DSSS integrated with solar operated vacuum fan and external water cooled condenser was fabricated using aluminium material. During sunny season, experimental investigations have been performed in both conventional and modified DSSS at a basin water depth of 3, 6, 9 and 12 cm. Production rate and cumulative distillate yield obtained in traditional and developed DSSS at different water depths were compared and best water depth to attain the maximum productivity and cumulative distillate yield was found out.

Results indicated that both traditional and modified double SS produced maximum yield at the minimum water depth of 3 cm. Cumulative distillate yield of the developed SS was 16.39%, 18.86%, 15.22% and 17.07% higher than traditional at water depths of 3, 6, 9 and 12 cm, respectively. Cumulative distillate yield of the developed SS at 3 cm water depth was 73.17% higher than that of the traditional SS at 12 cm depth.

Performance evaluation of DSSS at various water depths by integrating the combined solar operated Vacuum fan and external Condenser.