This work focuses on generating wind power by incorporating the kinetic energy of the head wind, during deceleration of heavy vehicle like a train by placing multiple wind turbines on the rooftop of individual coaches. Turbine working on principle action of drag force like the simple Savonius rotor is operated during deceleration of the vehicle. Drag mitigation during zero and constant acceleration motion is achieved by covering the effective turbine cross section with symmetrical airfoil flaps which also guide the wind at the turbine blades during deceleration with the help of mechanisms explained in this study. Theoretical efficiency analysis is performed for specific trains of Indian Railways considering the surplus weight of the mechanism, increased drag and power required to operate the flap mechanism. Feasibility and payback calculations by taking into account the efficiency and estimated construction and maintenance cost of the mechanism, are performed. Investigations regarding the effect of parametric variations in operating velocity, the number of stops, number of coaches and number of trips per day reveal that increasing the values all these parameters help in mitigating the energy production cost. This system will prove more efficient for trains with high operating velocity and high number of stoppages like the metro trains.

Computational analysis has become a very useful tool for a detailed understanding of building physics before actual building constructions and for predicting such system behaviors where massive urbanizations are envisaged. The present study attempts to describe the efficacies of CFD as an "analysis led design" tool, where a computationally modeled cross-ventilation system with asymmetric positions of openings is analyzed to estimate the comfort zones according to the PMV (predicted mean vote) model for evaluating the influence due to roof inclinations, thereby providing opportunities in rectifying any anomalies pertaining to it, prior to the actual construction. A numerical analysis has been carried out to examine the effects of natural ventilation in a wind-driven system using the established extended PMV model (PMV e). The study focuses on thermal comfort and the effect of roof inclination angle over the three different weather conditions in Delhi-winter season (high humidity and low temperature), summer season (low humidity and high temperature) and monsoon season (high humidity and mild temperature). Appropriate roof inclination angles provide a better ventilation rate and air distribution pattern, which significantly affects comfort condition. Study shows that for winter season, the PMV values decrease as the roof inclination angle is increased and the ventilation rate for 30° inclined roof increases about 16% as compared to the flat roof case, while PMV values increase with roof inclination for summer season, signifying zone of discomfort. It also concludes that a moderate roof inclination is beneficial for monsoon season.

The present study deals with the analysis of stochastic transient pressure variations and wall impacts for scaled down models of LNG carriers by using the VOF technique for interface characterization. Numerical simulation of sloshing under sway using multiphase liquid-gas condition has been carried out. Use of VOF method for multiphase numerical simulation is compared with the results of previously performed SPH study and established sloshing experiments. The efficacies of the VOF interface capturing technique is established by comparison with high-resolution images taken during sloshing experiments performed under the same external excitation frequency, amplitude and fill level. The pressure data from experiments when compared with respective simulations involving SPH and VOF methods helps to capture the fluid flow behaviour and intricacies they can handle.

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