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In these modern times, the requirement of the energy is not always constant but often periodic. In a hot climatic country like India, a large amount of energy is consumed in cooling application. A heat-exchanger which can store the thermal energy during off-peak hours and use the same energy during peak hours for cooling applications may flatten the periodic energy requirements. Water has a very high value of latent heat of fusion. This latent heat can be utilized to store the thermal energy and use it at a later stage for cooling purposes. The cooling temperature management will be more effective during the phase change process due to the constant fluid temperature. The present study analyzes the heat transfer performance of Ice-Freezing type phase change material (PCM) based heat-exchanger (HEX) during the solidification process. The prediction of solidification time and variation of heat transfer coefficient (HTC) under various configurations is performed. commercialized computational fluid dynamics (CFD) software, Fluent 19 is used to analyze the solidification phenomenon in water. To evaluate the optimum element size, Mesh-independent study is conducted on a single block. Initially, the single block is considered for analyzing the solidification process. The simulations are performed on multiple pipe with varying pitch. The results indicated a drastic change in solidification time as the pitch is decreased. An optimum pitch has to be decided based on the application. The transient variation of the HTC during the solidification process is studied. Initially, during the sensible cooling stage, the HTC decreases at a faster rate. While during the solidification process, the transient variation in HTC is less.

The aim of this research work is to optimize material removal process parameters using CNC turning operation to get the desired value of the surface roughness. With an orthogonal array of L27, the Taguchi approach is used where three levels of each parameter are taken into account, which are cutting speed, feed and nose radius. The experiments were done on EN8D carbon steel and a carbide insert was used for a total run of 27 experiments. Using the surface roughness tester, the roughness values were obtained. Analysis of variance (ANOVA) was executed on Minitab software to recognize the impact of individual machining parameter on surface roughness. Regression equation is prepared from the experimental data and validated by performing random experiment.

Fibers are the main load-carrying member in composites. Hence, it is required to examine the behavior of fiber against different strain rate (SR). In present study, the behavior of natural fiber (NF) and Natural fiber yarn (NFY) is investigated by varying the SR at lower SR: 0.17 × 10−4 s−1 to 1.25 × 10−4 s−1 (crosshead speed (CHS): 0.1 to 0.75 mm/min) and higher SR: 1.25 × 10−4 s−1 to 25.00 × 10−4 s−1 (CHS: 0.75 to 20 mm/min) and measure its effect on tensile strength (TS). Here, the range is proposed for SR of lower SR and higher SR. NF: hemp fiber, sisal fiber and banana fiber and NFY: flax fiber yarn, bamboo fiber yarn and cotton fiber yarn are procured for the tensile testing. The mathematical models: exponential model (EM), linear model (LM), logarithmic model (LOM), polynomial model (PM) and power model (POM) are also proposed to predict the TS at different SR. The paper signifies the outcome as: TS increases gradually at lower SR and decreases gradually at higher SR; PM is advised to use in the prediction of TS at lower SR and higher SR for NF and NFY.

Increased competition in market has forced small and medium scale industries to re-examine their methods of doing business. Corrosion cannot be eliminated completely and considered as major problem in industries. In Last decades industries have implemented corrosion prevention technique in order to sustain the competitive market. pH level of water used by customers based on geographic location and heating cycle affects most on metal parts of water heater. It results in pitting corrosion and reduction of life cycle with increased maintenance cost. Corrosion issues needs to be properly understood with prescribe necessary kind of treatment to ensure a long life span of the water heater. Many factor affects the material such as temperature, presence of moisture, reduced performance due to environmental effect and life of the water heater. Life cycle is improved when both inhibitor and protective coating method such as galvanizing, thermal spraying sacrificial method, impressed current, Zinc paint are used together or when protective coating is used together with cathodic protection. In present work authors have made an attempt to study Industrial economic aspects of corrosion issues in water heater and its prevention techniques analysis. Effect of galvanizing in various environments such as normal water, heated water and salty water is tested on metal parts and it has shown significant reduction in corrosion. Study of various corrosion prevention technique is focused on reduction in corrosion rate there by reducing the rework.

Finite volume method (FVM) has been implemented to envisage the influence of crank angle on pressure variation, turbulent kinetic energy and velocity distribution in two stroke engine. A three dimensional Fluent-Computational Fluid Dynamics (CFD) tool of ANSYS 15.0 was used to reveal these variations for increasing volume scavenging efficiency. Crank angle was varied from 86.25° to 300° for predicting behavior of exhaust gases in scavenging process. Highest volume scavenging efficiency was measured at crank angle of 300°. The results showed that volume scavenging efficiency highly depend on crank angle which will directly affect combustion process. By doing so, one can able to modify the configuration of intake ports and have better exhaust gas-charge out of the cylinder and drawing in a fresh draught of air or fuel/air mixture for the next cycle.