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The prospective generation of Unmanned Aerial Vehicles (UAVs) can attempt to eliminate conventional primary control surfaces, thereby seeking to enhance operational efficiency. This endeavor constitutes an experimental manifestation of morphing principles utilizing Shape Memory Alloy (SMA), specifically Nitinol, to actuate control surfaces through a meticulously orchestrated application of power cycles at diverse frequencies. The integration of Morphing Technology has garnered heightened attention within the aviation industry, owing to its capacity to augment efficiency and performance across a spectrum of flight conditions. The intrinsic appeal of morphing lies in its potential to dynamically alter wing geometry during flight, thereby optimizing fuel efficiency and mitigating environmental impact through diminished carbon emissions resulting from reduced drag. This, in turn, necessitates reduced thrust to achieve similar or same performance levels.

This paper studies the “Experimental testing of spray characteristics of swirler injector without guide vanes in Liquid Propellant Rocket Engines”. The purpose of a fuel injector is to inject and control the flow of the propellants into the combustion chamber. It consists of Tangential ports, a swirls chamber, a converging spin chamber, and a discharge orifice. Kerosene as fuel and liquid oxygen as oxidizer were employed here. To pressurize the propellants, nitrogen gas is used and the pressurized pipeline is controlled with an open/close ball valve and measure the inlet pressure using a pressure gauge. When a propellant comes through the inlet has a tangential velocity and it causes the propellants to swirl inside the swirl chamber at the exit the propellant comes with rotational momentum and forms a liquid film and then the friction between the propellant and air accelerates and disrupts the liquid film and converts into very tiny droplets.

To achieve healthier and sustainable air quality and to protect human life, worldwide emission standards are being tightened for harmful vehicular air pollutants such as CO, hydrocarbon, NOx and particulate matters. Among selective catalytic reduction catalysts for NOx control in automotive after treatment system, Cu-SSZ-13 (Chabazite structure) is one of the most promising SCR catalyst, mainly used in light and heavy duty diesel vehicles. This article focuses on the development of Cu-SSZ-13 with desired properties such crystallinity, morphology, surface area and Cu loading in the catalyst. With the help of sophisticated catalyst characterization tools such as NH3-Temperature Programmed Desorption (TPD), Temperature Programmed Reduction (TPR), BET surface area, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM), novel and highly active formulations of Cu-SSZ-13 are reported here.

With the emphasis of electrification in automotive industry, tremendous efforts are made to develop electric motors with high efficiency and power density, and reduce noise, vibration and harshness (NVH). A multiphysics simulation workflow is used to predict the eccentricity-induced noise for GM’s Bolt EV motor. Both static and dynamic eccentricities are investigated along with axial tilt. Analysis results show that these eccentricities play a critical role in the NVH behavior of the motor assembly. Transient electromagnetic (EM) analysis is performed first by extruding 2D stator and rotor sections to form 3D EM models. Sector model is duplicated to form full 360-degree model. Stator is split into three rotated sections to characterize stator skew, and the skew between two sections of rotor and magnets are also modelled. Sinusoidal current is applied and lumped-sum forces on each stator tooth are computed.

This paper presents an experimental setup and an equivalent FEM simulation methodology to accurately predict the response of Engine Control Module (ECM) assembly mounted on a commercial vehicle subjected to road vibrations. Comprehensive vibration study is carried out. It involved Modal characteristics determination followed by random vibration characterization of the ECM assembly. A hammer impact experiment is first performed in lab to estimate the natural frequencies and mode shapes of ECM assembly. Mounting conditions in test specimen are kept similar to the actual mounting settings on vehicle. Natural frequencies and mode shapes predicted from free vibration experiment are compared with finite element (FE) based modal analysis. The importance of capturing the assembly stiffness more accurately by incorporating pre-stress effects like bolt-pretension and gravity, is emphasized.

Diesel engines are becoming popular because of more fuel efficient and durability. While the CO and HC impurities are significantly lower than in gasoline engines, the design strategies for reduction of Particulate Matter and Nitrogen Oxides remain a major challenge for environment. The work mainly focused on reduction of NOx from diesel engines using SCR technology under Indian driving conditions and furl availability. With BS III/IV fuel available in the country, the catalyst system of choices the Vanadia Tungsten Titania (VWT) system because of its proven resistance to Sulfur poisoning. However, under urban driving conditions on Indian roads, the major obstacle is the low engine out temperatures which are below the normal operating temperature window (200 to 450 °C) of VWT - SCR.

Diesel exhaust is typically at lower temperature compared to gasoline exhaust and would need a catalyst that has activity in low temperature range to be effective. Hence considerable research has been directed to improve low temperature activity of catalysts used in diesel application. One of the aspects that has been widely reported in literature is that small Pt clusters have a positive effect on reducing the CO light off temperature (LOT). To examine this phenomenon closely, the present work was taken up to correlate Pt cluster size with performance. Catalysts were prepared on various supports - Alumina, Siliceous clay, ceria-zirconia, etc with different metal loadings and the calcinations conditions were varied both in time and temperature as well as calcinations atmosphere. The cluster sizes were ascertained using Phillips Tecnai 20 Transmission Electron Microscope.

Vapor management system is critical to manage fuel tank capacity, evaporative emissions and pressure control for hybrid applications. Due to stringent emission norms and other regulations there has been lot of advancements in design and application of vapor control valves that are used in automotive fuel tanks. Continuous exposure of these valves to fuel vapor or fuel in some instances led to swelling of assemblies and poses serious threat to product functionality and maintaining required tolerances. Swelling of plastics in fuel is ideally a case of multi physics, which involves modeling of complex mass transfer phenomena. In this study a simple thermal analogous approach has been used to model swelling behavior by characterizing the basic plastic-fuel soaking through coefficient of hygroscopic swelling. Extensive testing has been performed with multiple plastic-fuel combinations with different shapes at different temperatures.

Small Commercial Vehicle (SCV) is an emerging Commercial Vehicle (CV) segment both in India and throughout the world. Vehicles in this segment have diesel engine of capacity less than 1 l and GVW of less than 3.5 t. Normally for the CV, engines are tested on engine dynamometer for emission test, but SCV are tested on chassis dynamometer as they are classified as N1.1 class vehicles. Hence SCV have to follow same emission regulations as diesel passenger cars. The main challenge is to meet BS-IV NOx and PM emission target together with high torque optimization along with required durability targets. This paper addresses this challenge and reports the work carried out on an Indian SCV with 0.7 l naturally aspirated indirect injection diesel engine.

Technologies for exhaust aftertreatment of diesel engines are driven by emission standards and Selective Catalytic Reduction (SCR) will play a key role in complying with the requirements, particularly for the heavy duty vehicles. Amongst the variety of catalysts for the SCR reaction, the Vanadium-Tungsten-Titanium-Based (VWT) system is preferred over the base metal doped zeolite because of the established advantages of wide temperature window, robust and durable performance and resistance to sulfur exposure. While the basic chemical reactions involved in ammonia-SCR are well known, the challenge lies in identifying the right combination of substrate and wash coat formulation to meet with customer specific requirements. An insight into the relevant materials properties of the substrates as well as the bulk surface properties of the wash coat such as its ammonia storage capacity, V2O5 dispersion and stability are important.

A computer based data acquisition and power control system has been designed and installed for conducting thermal test at 4M thermal vacuum chamber of ISRO Satellite Centre(ISAC), Bangalore, INDIA. The system consists of four main units viz. Temperature Signal Processing Unit(TSPU), Power and Control Unit(PACU), Spacecraft telemetry and thermal vacuum chamber facility data interface unit and Data Processing Unit(DPU). The system has capability of monitoring 512 thermocouple channels, 700 spacecraft telemetry thermal related parameters, facility parameters including chamber Vacuum level, chamber contamination level using Quartz Crystal Monitor data and 128 numbers of heat-flux/temperature control channels. TSPU and PACU are VME based system. DPU is based on Pentium processor with hot redundancy using Redundant Array Of Inexpensive Disks(RAID) to takeover in case of failure of a server. All the subsystem and their peripherals are networked using TCP/IP on Ethernet.

In India, during 1992, two wheelers numbered around 17 millions compared to only 2.8 million passenger cars. Two wheelers are estimated to consume about 60% of the total gasoline annually. Very little information however, is available on the octane number requirement of two stroke engine two wheelers. In this study, octane number requirement (ONR) of 13 makes of two wheeled vehicles constituting the bulk of current production was measured using full boiling range gasolines as well as primary reference fuels. Knock intensity was measured by an instrument which measures and analyzes cylinder head vibrations in the frequency range of 5 to 12 kHz. Among different makes, ONR varied from 51.5 to 101 research octane number (RON) and 48-86 motor octane number (MON). ONR of the 2-stroke engine powered vehicles measured using primary reference fuels was found to be closer to MON of the full boiling range reference fuels.