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The effects of the aspect ratio of the building due to Wind-Driven Rain (WDR) is considered for the present study. The modelling is carried out using an open-source CFD code namely OpenFOAM®. The simple Foam solver is used for generating velocity field data and the same was used by wind Driven Rain Foam solver to generate the catch ratios and specific catch ratios. The validation is carried out for a standard building with an aspect ratio of 4 by using the contours of the catch ratio. The Aspect Ratio (AR) is the ratio of building height (H) to building width (W). The present study considers AR of 0.5, 1, 2, 3, and 4. The results obtained from the simulations in terms of the response coefficient, streamlines, and other parameters are discussed in detail. [ABSTRACT FROM AUTHOR]

The present work is about the feasibility study of a negative ion generator for flow control. The experimentations were carried out on a jet impingement facility using the smoke visualization method. The results showed a significant effect of the ion wind on the downstream free jet. The significant outcomes were the change in the length of the potential core along with the entrainment width and subsequent flow characteristics analyzed at different Reynolds numbers. [ABSTRACT FROM AUTHOR]

The present study is about the acoustic noise levels and flow visualization for jet flow from a coaxial pipe with a circular cross-section and six flat vanes. Experiments are conducted using a high-pressure settling chamber facility and images are captured through compressible flow visualization technique. The results of noise levels and flow visualization were obtained for nozzle pressure ratios ranging from NPR 2 to NPR 5 and the same are compared between forward and reverse configurations. [ABSTRACT FROM AUTHOR]

In this present work, jet noise level measurements and flow field characteristics of coaxial flat vane Swirlers are investigated out experimentally to calculate the efficiency of the passive control regime. This induces swirl from six flat vanes with vane angles varying from 0֯ to 60֯. Experiments were carried out using high-pressure open jet facility and images are captured through visualization technique. The results of noise levels and flow visualization were obtained for nozzle pressure ratios ranging from NPR 2 to NPR 5 and the same are compared between low and high swirler configurations. [ABSTRACT FROM AUTHOR]

The satellite launch vehicle, GSLV has a cryogenic upper stage, which uses the cryogenic engine. In order to test and qualify the upper stage engine, used in a high-altitude Test Facility is used. The HAT facility is configured with a vacuum chamber, a second throat diffuser, a gas cooler, and an ejector and the diffuser system. Each subsystem has to be analyzed numerically and optimized for its better performance. This report deals with the Ejector system. In the first step, the basic dimensions of the ejector are derived from the one-dimensional gas dynamic equation. This report describes the performance of Ejector (designed by ID), the need for optimization, optimization of the Ejector system using CFD. A 2 – dimensional axis-symmetric geometry with nozzle and mixer system is considered for the analysis. A two – dimensional structured mesh, standard k-ε modeling for turbulence and species transport (not reacting) equations for species transport is considered for the analysis. The effect of varying the Nozzle exit diameter was studied to optimize the ejector for both no-load and full load conditions using CFD fluent software. It is found that the suction pressure at no load and full load for area ratio 4.6 is the lowest and it is matching with the one-dimensional value as per the design document of Cryo- rocket engine HAT facility Based on the result the optional area of 4.6 is arrived for the desired no load and full load pressure. The tangential shear mixing of passive and active fluid is achieved as the area ratio 4.6. It is found that the suction pressure at No load and full load for the distance of 925 mm and it is matching with the one-dimensional value as per the design document of the Cryo-rocket engine HAT facility. In general, no-load pressure parallel the small spacing from mixture throat at the minimum and full load pressure parallel be higher. Based on the above result the spacing of 925 mm is suitable for the no-load and full load pressure requirement. It is found that the suction pressure at No load and Full Load for pressure 25 bar is the lowest and it is matching with the one-dimensional value as per the design document of Cryo-rocket engine HAT facility. The ejector mixer throat is designed for the chocking condition of the desired flow rate. Based on the above, the optimum of the GN2 supply rate of 60 kg/s is best suitable for the desired no load and full load condition. [ABSTRACT FROM AUTHOR]

Weapon technology is one of the most developing technologies in the world, but military guns are still using gun powder (chemical propulsion) to propel the bullets from the gun. The objective of the proposed work is to replace the gun powder with electromagnetic propulsion to achieve the high-velocity impact of the bullet on the target. This proposed research, the electromagnetic gun works based on the principle of the Lorentz force. The Experimental work is done on the gun-rails made up of copper and bullets (projectile) made up of aluminium alloy, the capacitors connected in parallel for providing the flow of high current. [ABSTRACT FROM AUTHOR]

Flow analysis is considered to be the most crucial procedure in aerodynamics. Analysis of flow and its parameters over any object has to be done with considering aerodynamic loading acting over it. In the field of aerodynamics, wind tunnel test setup is used for flow analysis. The wind tunnel test section should always afford a laminar and uniform flow to provide exact results during flow parameter determination. But attaining cent percent laminar flow inside a wind tunnel test section is practically not possible. Hence there is an immense requirement of performing calibration before starting any research experiments in a wind tunnel. It is to be noted that wind tunnel calibration is done with ultimate care to avoid any error in the analysis. Generally a Pitot - static probe is used to calibrate subsonic wind tunnel. But the Pitot - static tube has many limitations like single point data sensing. Hence a new efficient and compact instrument has to be developed for the calibration of wind tunnels. In this paper, a yaw sphere is designed and analyzed to perform the calibration of a subsonic wind tunnel. [ABSTRACT FROM AUTHOR]

This paper includes the study on analysis, fabrication and testing of a lightweight sandwich composite made by balsa wood core and fiber-glass/polyester resin for an UAV wing. The analysis for von mises stress distribution is done using COMSOL software. The materials play an important role in the design of any engineering process and therefore must have the ideal properties required for a particular function. It is more important for the airframe designers as weight is a major criterion in aircraft design. The sandwich structure exhibits high flexural strength which is the primary necessity of a wing to counter bending loads. The balsa wood core structure exhibits better structural strength properties than that of polyurethane foam-based cores. The sandwich composite developed exhibits satisfactory mechanical properties for the required application. [ABSTRACT FROM AUTHOR]

Laminated panels play a vital role during the ballistic projectile impact which causes, a major structural deformation for the body of an aircraft. The important part of the hard laminated panel is to act as protective armour and the panel must be efficient enough to withstand adverse condition during its mission. The current examination has concentrated on the ballistic reaction of K29 and K129 woven Kevlar texture laminates. The experiments were carried out with laminated Kevlar composite plates directly impacted by two rigid projectiles of 7.5mm diameter steel cylindrical bullet and 9 mm hemispherical bullet. These plates were impacted at different velocities range from 150 to 250 m/s. LS-DYNA was used to model and simulate the projectile impact. FE simulation of the impact tests precisely anticipated the back face displacement (BFD) giving the maximum dynamic displacement and dynamic reaction for the conical projectile impacts, while the BFD for the hemispherical shots was low. Significantly, the numerical analysis precisely anticipated the residual velocity for the hemispherical impacts and time taken to at most extreme BFD for the cone shaped shots. Experimental testing and numerical simulation results were compared to analyze the behavior of composite laminates and the results shows good correlation. [ABSTRACT FROM AUTHOR]

As these days increase in light weight composite materials with flexibility and long life but low in cost are highly in demand. These composite materials also need maximum strength and durability. GFRP is one of the best option in industries, because of rapid industrialization and modern development, everybody want robust and smart structure. GFRP is also known as fibreglass, made up of synthetic plastic and extremely fine fibres. And due to its large number of application and bulk properties like stiffness, flexibility, corrosion resistance etc., this composite material is more in demand other than other composite materials and also less expensive than other composite materials. GFRP plays very vital role in aviation industries, nowadays scientists are working on making light weight aircraft with composite materials. There are some of aircraft using GFRP materials are fuselage door, aileron, interior parts of aircraft, spoiler and elevator. Not only in aviation industry GFRP composite materials are also has high demand in industries like automotive, wind energy, defence, marine and construction etc. This research is to investigate the damages on GFRP composite materials due to Aqueous Substance. For this experiment GFRP Laminated Plates has been undergone a period of 30days observation, submerged into ATF(Aviation Turbine Fuel) and Salt Water. After completion of 30days of observation to determining the damages laminated plates were tested under quasi static bending test. The obtained results have been compared with neat GFRP sample bending result. And observed the changes have been made in flexural strength of the composite materials. [ABSTRACT FROM AUTHOR]

Modern day aerodynamics has applications in various domains ranging from design of ballistic shells to ground vehicles exceeding sonic speeds. The conceptual design and analysis of such extreme applications require test beds of the same calibre which are able to comply with the complexity of the working mechanism. Wind tunnel is one such apparatus where scale models of the prototypes can be tested. Alike all apparatus even wind tunnels has to be calibrated on a regular basis which ensures that the readings obtained from the instrument are acceptable and the error margin are within the limitations. Thus there is a need for instruments which can accurately measure the various properties of the wind tunnel, namely the flow angularity, velocity distribution, speed setting etc. Taking into account the various requirements a claw yaw is designed, simulated and tested in a wind tunnel and the results are discussed. [ABSTRACT FROM AUTHOR]

The Aero-Aquatic vehicle or amphibious aircraft, a machine that runs in both air and inside water, it is a breakthrough in the application of aircraft and vehicle which runs underwater. By this, there will be a wide application advantage in defence and civil field, the research purpose is to design an underwater aircraft which could run efficiently in both air and water by using techniques like morphing wing, morphing tail and external ballistic tanks which makes the vehicle counterbalance from all the angles, the inclusion of bionics are there in this research, By taking consideration of sustaining UAV models, manned amphibious vehicles and morphing wing designs. The design was undergone both hydrodynamic and aerodynamic analysis to know the flow characteristic. The complete designing and analysis are done in AUTODESK & CFD-ANSYS to know accurate results. The air-water transition, the adaptive wing structure between air and water which is also known as morphing wing, the different propulsion type, and it also summarized the power source. Furthermore, the application scenario of bionics is summarized. It is challenging to satisfy the structural characteristic of aircraft due to the density of water. This research will answer the question regarding the co-relation between hydrodynamics and aerodynamics. Further research and development (R&D) is required to improve and implement the Aero-Aquatic vehicle. [ABSTRACT FROM AUTHOR]

Prediction of dynamic characteristics of turbomachinery components (such as compressor & turbine rotors) of a gas turbine engine is very important to ensure safe operation. The rotor blades shall be designed such that, their natural frequencies do not coincide with possible excitation sources in the engine in order to avoid resonance. During the design phase, natural frequencies and associated mode shapes need to be predicted through computational methods. After the component is made, it is also essential to measure its dynamic characteristics through experimental modal analysis. In this study, a centrifugal compressor rotor of a small gas turbine engine is considered. Detailed numerical modal analysis was performed using ANSYS FEM software package. By the OROS modal analysis arrangement, the tentative modal analysis was carried out. The analysis was carryout at Propulsion Division, National Aerospace Laboratories. The results derived from the experimental analysis were compared with numerical analysis and were found to be a good agreement. The frequencies of blades have enough separation margin from the possible excitation frequencies. [ABSTRACT FROM AUTHOR]

This paper investigated in recent years the upgradations of existing parts have significantly increased the performance. The Swirling effect of the nozzle when there is a change in the geometrical shape of the nozzle orientations. These nozzles are operated with subsonic Mach number. Since in the subsonic regime, swirl characteristics are signed by the design & orientations of nozzle describes the gas dynamics behaviour in the fluid flow properties. Expansion of the fluid flow describes the static variation using Bernoulli's and continuity equations. The computational domain is created at the nozzle end part. The swirl arrangement geometry is done by the titling the geometrical points of the initial and exit nozzle design domain. This paper provides guidelines and procedures for incorporating these swirl characteristics and curl the nature of the fluid flow. The turbulent model of the computational is usually model with K – Epsilon turbulence model. The streamline, velocity plots and vorticity results of the numerical simulation recorded with the best fit swirling patterns in the nozzle are recorded. [ABSTRACT FROM AUTHOR]

The pressure driven shear flow is passed through the constant diameter was analysed through convergent nozzle act as primary flow of the nozzle. The secondary flow of the nozzle is impinged at the exit of the convergent nozzle. The convergent nozzle is designed with 4 passive tabs of rectangular geometry placed around the internal section of the nozzle with equal distance. The two jet impingements were placed at the exit of the convergent nozzle at 90-degree interval along with nozzle exit diameter of 20mm. The effectiveness of jet impingements at the exit of nozzle numerical work was carried out. The l/d ratio was calculated and it was operated with different pressure ratio and velocity ratio for evaluation of the jet. At the nozzle's exit, the rectangular computational domain was created. For the given velocity ratio, the prediction of the practical basic fluid flow parameters like pressure and velocity was done by computational analysis variation of pressure and velocity is measured. These variations have been inferred by evaluating counters figures and plots. The computational results shows that the flow has been delayed due to the passive tabs at the middle section of the convergent nozzle. The streamline and velocity plots shows that the directional change of the nozzle exhaust is made by the jet impingements and the flow get accelerated too. The formation of the vortices are present and was driven due to the jet impingements. The prediction parameter of the passive tabs makes the flow to get little swirl and makes the momentum of the flow to be higher order increased and curling nature of the flow makes the nozzle to be more stable The pressure driven shear flow is passed through the constant diameter was analysed through convergent nozzle act as primary flow of the nozzle. The secondary flow of the nozzle is impinged at the exit of the convergent nozzle. The convergent nozzle is designed with 4 passive tabs of rectangular geometry placed around the internal section of the nozzle with equal distance. The two jet impingements were placed at the exit of the convergent nozzle at 90-degree interval along with nozzle exit diameter of 20mm. The effectiveness of jet impingements at the exit of nozzle numerical work was carried out. The l/d ratio was calculated and it was operated with different pressure ratio and velocity ratio for evaluation of the jet. At the nozzle's exit, the rectangular computational domain was created. For the given velocity ratio, the prediction of the practical basic fluid flow parameters like pressure and velocity was done by computational analysis variation of pressure and velocity is measured. These variations have been inferred by evaluating counters figures and plots. The computational results shows that the flow has been delayed due to the passive tabs at the middle section of the convergent nozzle. The streamline and velocity plots shows that the directional change of the nozzle exhaust is made by the jet impingements and the flow get accelerated too. The formation of the vortices are present and was driven due to the jet impingements. The prediction parameter of the passive tabs makes the flow to get little swirl and makes the momentum of the flow to be higher order increased and curling nature of the flow makes the nozzle to be more stable than expected. [ABSTRACT FROM AUTHOR]

This paper investigates the mechanical behaviour of untreated High Carbonised High Chromium steel (HCHCR) with cryogenically treated HCHCR concerning its hardness. To enhance the properties like wear resistance, hardness, and toughness, the conventional heat treatment process was used. Nitriding and carburizing are the most widely used heat treatment process for surface treatment, tempering, and hardening. But 100% transformation of austenite at room temperature into martensite doesn't take place in any conventional hardening process. Even after the quenching process, some of the austenite remains in the martensite matrix and is retained as austenite. The austenite remaining in the martensite matrix exerts internal pressure in the structure and controls the expansion properties of the steel. The HCHCR material was quenched with liquid nitrogen and run at a low temperature of -80 ° C to -196 ° C for several hours. It converts austenitic resin to martensite and improves the grain structure of the steel. The results obtained show that retained austenite is converted to martensite, thereby increasing the hardness of the steel. [ABSTRACT FROM AUTHOR]

Sandwich structures have excellent energy absorbing capabilities and can be used in applications where the area of focus is impact protection. The response of foam core sandwich panels with carbon [C3/Foam/C3] and Kevlar [K3/Foam/K3] face sheets subjected to projectile with flat and hemispherical was compared experimentally and numerically. The sandwich specimens with different face sheets were fabricated using Vacuum Assisted Resin Transfer Moulding(VARTM) method. A single-cylinder gas gun was used for accelerating projectiles with 9.00mm diameter with different velocities between 40m/s-120m/s. From the experimental results the damaged area, depth of damage is correlated with the nose shape and velocity. The numerical simulation carried out using LS-DYNA showed good correlation with the experimental results. The results shows a superior impact force carrying capacity for the kevlar face sheet sandwich panel in comparison with the carbon face sheet sandwich panel impacted at the same velocity and projectile shape. [ABSTRACT FROM AUTHOR]

Fourteen airfoils were selected in this research paper to build and optimize a small horizontal axis wind turbine for a low wind speed. By using Q-blade software and CFD simulations for a 0.5 m rotor radius and the tip speed ratio ranged from 3 to 10. In this paper selected airfoil such as E205, E214, E216, NACA2412, NACA4418, SG6040, SG6041, SG6042, SG6043, S1221, S2091, S7012, SD7034 were investigated. As the most suitable geometries, Airfoil E216 and SG6043 cast out by checking numerical simulations to gain more power at low Reynolds number. In this study comparing the drag coefficient, lift coefficient and lift to drag ratio with respect to angle of attack, the airfoil has been revised. A parametric optimization of the blade geometry and develop the new airfoil for small wind turbine rotor. The E216 airfoil is found to be better performance with below solidity of8.25%, while the NACA 2412 produces stronger solidityof 21.6% due to wake effects produced behind the rotor. A wind tunnel test, Q-Blade simulation and CFD analysis were performed on the design and optimized for the proposed small horizontal wind turbine rotor axis in order to apply low wind speed area. [ABSTRACT FROM AUTHOR]