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This paper discusses the aerodynamic flow characteristic of car with various rear shape car body. 80 to 90% of total aerodynamic drag will occurs from base pressure which is created by pressure difference of front and rear side of car. Increasing of pressure difference mainly occurs due to rear end shape of car while it is moving. The proper shape of car, which give less drag and better stability and handling of vehicle by creating streamline flow over the vehicle. For this study, we choose passenger cars with various rear shape such as Hatchback car, Sedan car, Square back car and Fastback car. The experimental work was done in open circuit subsonic wind tunnel with the subscale model 1:10 of all rear shape model at various velocities. The aerodynamic coefficients of drag, lift and pressure (Cd, Cl, and Cp) of car models are plotted to understand the effects of flow condition form the experimental work. The experimental results revels that the sedan car and fast back car are having better aerodynamic performance compare to other car model. And also suggest that researcher will choose better option is hatchback or square back car model for further modification of rear end body to getting better aerodynamic performance.

According to the Global Aviation Development, The Unmanned Aerial Vehicles plays a vital role in leading the aviation industry. Designing an unmanned aerial vehicle with low Reynolds number and long endurance are the challenging task to achieve efficient flight. This investigation concentrated on the wing performance parameters that are influences the stability of solar power unmanned aerial vehicles. In general solar powered unmanned aerial vehicles can be operated in low altitude with very minimum velocity. Supporting to improve the flying qualities of solar powered unmanned aerial vehicles, ONERA M6 wing designed and validated in aerodynamic aspects. In this present work solar powered unmanned aerial vehicle is designed to be operated in the transonic region with swept wing configuration and often adhering to the phenomenon of Whitcomb Area rule. Satisfying the conditions of flight profile, the boundaries are far-field 3-dimensional, transonic, turbulent, and in viscid, flow simulations over the ONERA M6 wing about the respective angle of attack. Computational Fluid Dynamics Results have been validated for various flow conditions and which are best suits for operating the solar powered unmanned aerial vehicle in transonic region. Observation from the results and an optimization can be made in the autonomous wing body for conventional operation.

Single crystal of 4-(Dimethylamino)pyridinium p-toluenesulfonate (4DMPT) has been successfully grown by solution growth method and its structural characterization has carried out by X-ray diffraction methods. Single crystal XRD study shows that the grown crystal crystallized in the monoclinic system with unit cell dimensions a = 8.986 (6) A˚, b = 17.591 (5) A˚, c = 9.784 (8) A˚, β = 112.296˚(3), V = 1448.18 (17) A3 and Z = 4. The quantum chemical calculations have been carried out at HF and DFT (B3LYP/ CAMB3LYP/ M06–2X) with 6–311++G(d,p) levels to reach the optimized geometry, charge distributions and HOMO-LUMO nature. A good correlation is shown between computed and experimental structural parameters such as bond lengths and bond angles. The load dependent hardness values of the crystal have been analyzed. The optical spectrum revealed the ultra violet cut-off wavelength at 284 nm. The third order nonlinear optical responses have been studied by Z-Scan technique. The calculated value of third order non-linear refractive index (n2), third order non-linear absorption coefficient (β) and third order non-linear optical susceptibility (χ(3)) is 8.18 × 10 − 8 c m 2 / W , 0.20 × 10 − 4 cm / W and 12.88 × 10 − 6 esu, respectively.

In this paper, investigations on the crystal structure, vibrational, physical properties on charge transfer single crystals of 4-dimethylaminopyridinium bromide. Its structural parameters, vibrational, mechanical and optical properties have been studied by SCXRD, FT-IR, FT-Raman, Vickers microhardness test and Ultraviolet–Visible spectral analysis. The computational investigations were carried out to determine the molecular geometries, vibrational modes, HOMO-LUMO analysis, population analysis, MEP, thermodynamics and macroscopic NLO response of the compound. The theoretical and experimental molecular geometrical parameters and vibrational assignments have been in good agreement. Mulliken charge distribution of the present compound was studied systematically. The chemical hardness, electro-negativity and chemical potential of the molecule have been computed by HOMO - LUMO plot. FMO analysis indicates the electron delocalization on the title compound and also its low value of energy gap indicates electron transfer. NLO parameters were calculated by HF and DFT methods. The calculated hyperpolarizability values showed that the compound is a good candidate for NLO applications.

Development in the area of autonomous motion planning has enabled the utilization of fully autonomous Unmanned Aerial Vehicles (UAV). This would enable unmanned vehicles to take shorter paths and avoid collisions in obstacle rich environment. The approach is analysed on a sampling based algorithm, rapidly-exploring PYTHON software. This article proposes an algorithm called ‘Haversine theory’ building on the basic algorithm, providing an alternative to probabilistic location, thereby avoiding local collision. The approach is a benchmarking for kinematic car, dynamic car and a quadrotor and the results show improvements in length of the motion plans and the time of computing.

Increasing awareness on environmental protection is being noticed by aviation industries to develop aircraft with light weight and minimal environmental impact; for this purpose, environmental impact (EI) of aircraft to be determined. This article presents life cycle assessment (LCA) of turbine blade used in aircraft engine system. LCA can provide detailed information about chosen material or component from its manufacturing to disposal phase. Environmental impact (EI) of various entities is being analysed using LCA package. LCA has been mainly focused on the environmental impact of the life cycle phases of components. The assessment results showed that plating has highest impact followed by raw material. The conduct of the study enables the determination of environmental impacts over the life cycle of aircraft components.