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A boxfish has certain aero/hydrodynamic features in its body shape which makes it more efficient in traveling through the water using less energy. Because of the streamline features of the boxfish, it produces less drag for its movement. So, there is a lot of possibility to design a passenger car by implementing the aerodynamic features on the car shape for improving the energy efficiency. This paper investigates the aerodynamic behavior of a boxfish using both experimental and computational methods. A scaled-up model boxfish was manufactured, and passenger car model was also developed by applied certain aerodynamic features on the car shape and a prototype was manufactured. The models were tested in a wind tunnel condition. The results indicate that the drag coefficient of a boxfish is around 0.24 which is significantly lower than current drag coefficient of a passenger car. The car design inspired by boxfish also energy efficient than a commercially manufactured passenger car. Hence, a boxfish shape can be adapted for achieving low drag and energy efficient motor vehicle design.

In Saudi Arabia, the current production of electric power is mainly relying on crude oil which causes a high percentage of carbon dioxide emissions and no power is generated from any renewable sources. However, recently Saudi Government has announced a development plan ‘The Saudi Vision 2030’ where the target is 20% of the production of power from the renewable sources mainly from solar and wind. Like other countries e.g., China, India, US and UK that produce a significant amount of their electric power from renewable sources. Saudi Arabia has a vast land area where there is a plenty of prospect to install renewable power plants (solar and wind farm) to generate a significant amount of electric power to meet their 2030 target. This paper analyses past 10 years wind data in various location of Saudi Arabia to investigate the feasibility to generate power. This study also recommends the potential locations that are suitable for wind power generation including suggestions of the wind turbine specifications.

Bridge pier are the most widely used hydraulics structures in ocean, offshore and river engineering. As a result, scour around bridge pier, flow prediction and it interaction are widely attracted by the civil, mechanical and marine engineers. The local scour around the piers of the bridge is one of the main causes of the bridge failure. The local scour of river water is a catastrophic effect on the engineering structures. It leaves them under dangerous, maintenance prone conditions and occasionally leads to loss of life. The damage to the hydraulic and civil structure due to local scour is a global problem and has been studied experimentally and numerically by many researchers for several decades. In this paper, local scour around bridge piers as a complex phenomenon has been explained and the problem to countermeasure the local scour effect. In past two decade computer simulations have been developed for bridge pier scouring. They have an advantage of being able to simulate a situation at full scale scenario, and can easily alter the geometry as required. Early CFD simulations were mainly focused on single-phase model which require empirical sediment transport equations to predict sand motion. Multiphase CFD simulation models are a most recent development; they model sediment transport as a granular flow to predict the sand movement and analyse the scour depth. The experimental validation will be undertaken using generic water tunnel. A series of scale models will be developed in the future as per the geometric characteristic of CFD models.

Local scour around bridge piers is one of the main causes of bridge failures. Study of local scour is very significant for the safe design of piers and other civil and marine structures. Despite the subject has been explored for many decades, the numerical developments have been very limited due to the complicated interaction of three-dimensional flow, sediment transport and fluid-particle interaction. In this work, a numerical model based upon the Reynolds Average Navier Stokes Equation (k-e) approach has been used for predicting the three dimensional flow (3D) around a bridge piers (square and cylinder piers), mounted on a flat and fixed bed. The main aim of this paper is the validation of the numerical model, based upon the previous experimental data. The CFD-numerical tool is proficient to qualitatively reproduce the flow characteristic for different pier shape and features around the pier, such as the upstream vortex (horseshoe vortex) and downstream vortex (vortex shedding in the wake). The outcome of this study can be used developing adequate numerical model to simulate the 2D and 3D turbulent flow past the square and circular piers, which are relevant case-studies for the marine and civil structures supported by pillars. The corresponding numerical results are in good agreement with those extracted from available experimental data.

Aerodynamics plays an important role on the external shape of the vehicle and any other additional structures such as deflector attached to it. It has been noted that significant numbers of light truck are manufactured and operated in the Indian subcontinent without any aerodynamic aspect. Therefore, the main objective of this study is to analyze the aerodynamic impact of several deflectors or fairings used in light trucks available in Bangladesh and Pakistan. The study was performed by computer modelling, rapid manufacturing of physical models, wind tunnel testing including computational fluid dynamics (CFD) analysis. Drag forces generated by each model were analyzed and compared. The results show that the deflectors used in most Bangladeshi and Pakistani trucks manufactured locally are not aerodynamically efficient as they can increase the overall aerodynamic drag by up to 22%. By replacing these deflectors with an aerodynamic shaped fairing can reduce the fuel consumption by 12%.