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Cold cracking is one of the major issues during welding High Strength Low Alloy (HSLA) 950A steel. The aim of the present research work is to optimize preheating temperature, the addition of oxide particles, and heat input using the Taguchi design of experiments for bead on plate, especially on the improved impact strength of weld metal. The experiments are carried out at three levels of mentioned parameters and Charpy impact strength is considered as a response. L27 orthogonal array is selected for experimentation in the present investigation using three parameters. An addition of vanadium oxide (V2O5) has acted as a nucleation site for acicular ferrite and enhanced the cold cracking resistance of investigated steel. The experimental results suggested that the impact strength of weldment is strongly influenced by pre-heating temperature (74.5%) and less influenced by oxide particle concentration (12.7%), and heat input (12.2%). Microstructure at HAZ revealed the presence of a small proportion of acicular ferrite of Widmanstatten morphology and upper bainite near weldment causes the reason for enhancement in cold cracking resistance. Fractographic examination revealed the presence of both ductile and brittle fracture modes, which attributed to higher and lower impact strength of weld joint respectively.

Desiccant wheel dehumidifier is filled with solid desiccants, looks like a honeycomb structure which is open on both ends. Air is allowed to pass through the honeycomb passages, giving moisture to the solid desiccant contained in the wheel. The wheel constantly rotates through two separate air streams. The first air stream, called the process air is dried by the desiccant. The second air stream, called reactivation or regeneration air is heated and dries the desiccant. The combination of desiccant materials such as chloride desiccant and organic desiccant is used here and dehumidification in the composite desiccant wheel has been studied experimentally. In this work, study performance of composite desiccant wheel with different air velocities, regeneration temperatures and at different inlet conditions was conducted and calculated the different performance indices of the desiccant wheel dehumidifier such as Dehumidification Effectiveness and Dehumidification Coefficient of Performance (DCOP).

The explosion of the population is alarming as the demand increases exponentially for resources. The freshwater resources are being exploited, and innovative and economical methods are analyzed experimentally to extract freshwater from various sources. Desalination performed using solar energy is an economical method to obtain fresh water from seawater and brackish water, which are available prolifically in nature. Since the phenomenon of desalination demands solar irradiation, which is an intermittent source of energy, distillation is not feasible in some places where the solar intensity is low. In the solar desalination, the saturation temperature of the saline water is very less at low saturation pressure thereby requiring large latent heat of evaporation. Hence, vacuum pressure could be the most appropriate choice to extract drinkable water in territories where the intensity of solar irradiation is poor. In order to this, the utilization of evacuated tube collectors and vacuum technology in the solar desalination unit has been considered for discussion as it is the most sought-after subject of interest in the current scenario. Methods for implementing the vacuum technology are also introduced with plenty of experimentations. Vacuum technology implemented in the evaporator of desalination system has been supplemented with nano-fluids and phase change materials to accelerate the evaporation process, increase efficiency, and obtain a greater productivity. In this review, the performance of the solar desalination unit under the vacuum effect were discussed in detail. Furthermore, in economic analysis, the cost effectiveness and cost per liter of distillate (CPL) were discussed to estimate the payback period. Finally, this review also suggests the vision to identify the future scope for additional implementations.