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Electric passenger car with floor battery usually have its front boot space empty and the space is used as additional luggage storage. This space can be utilized to capture the wind energy and generate electricity. Based on this, the objective of this work is to perform an aerodynamic analysis of an electric passenger car using wind turbine placed at the front. Initially the aerodynamic analysis of a basic electric car model is performed and further simulated using wind turbines and aerodynamic add-on-devices. The simulation is carried-out using ANSYS Fluent tool. Based on the simulation result, scaled down optimized model is fabricated and tested in wind tunnel for validation. The result shows reduction of drag coefficient by 5.9%.

Any change is vehicle exterior design, affects the aerodynamics characteristic. Generally different types of roof racks are attached on passenger vehicles to carry luggage which affects aerodynamic drag. The objective of this work is to perform aerodynamic analysis of ground vehicle with roof rack to investigate the change in drag coefficient. First, the aerodynamic analysis of a baseline passenger car model is performed with and without generic benchmarked roof rack at 100 kmph. Further analysis is carried out with different new designs of roof racks. Based on simulation result, a scaled down prototype model is fabricated and validated by using a wind tunnel test for optimum suitable case. The modelling of the vehicle is done in CATIA tool and simulation is carried out by using ANSYS Fluent.

Active aerodynamics can be defined as the concept of reducing drag by making real-time changes to certain devices such that it modifies the airflow around a vehicle. Using such devices also have the added advantages of improving ergonomics and performance along with aesthetics. A significant reduction in fuel consumption can also be seen when using such devices. The objective of this work is to reduce drag acting on a passenger car using the concept of active aerodynamics with grill shutters and air dams. First, analysis has been carried out on a baseline passenger car and further simulated using active grill shutters and air dams for vehicle speed ranging from 60 kmph to 120 kmph, with each active device open from 0° to 90°. The optimized model is then validated for a scaled down prototype in a wind tunnel at 80kmph. Vehicle has been modelled using SolidWorks tool and the simulation has been carried out using ANSYS Fluent.

Due to the transformation of the automotive industry from conventional vehicles to electric vehicles, new challenges have emerged concerning Electromagnetic Compatibility. Though the Radiated Emission limits in global regulation are the same for both types of powertrains of vehicles, however, due to the phenomena of conversion of high voltage to low voltage, rapid charging/discharging, and different components involved in electric powertrain, the Radiated Emission from electric vehicles give a strikingly different trend which is challenging to combat. When compared with the conventional Spark Ignition vehicle, many other electronic components of the electric vehicle stay in the mode of Power ON while in the “Ignition ON” steady state. This resulted in us observing a significant shift in the amplitude and frequency throughout the frequency band of Radiated Emission measurement.

An open wheeled open cockpit high speed car with 800 CC MPFI engine was developed validated and run at 105 kmph. The key focus was to build a car with superior aerodynamic characteristics especially in terms of drag. This work discusses in detail about the design and simulation of car using CFD package followed by Wind Tunnel testing. The design of high speed car starts with design of seat according to the ergonomics of the driver followed by the space frame. Based on the space frame designed, the body panels are sketched and CAD model is developed. The CAD model is imported in CFD package for virtual testing and validated through wind tunnel results. For this 1:3 scale model was manufactured using Rapid Prototyping.

A methodology for design and development of radiator cooling fan is developed with an objective to improve underhood thermal management. For this purpose an Axial Fan Design Software has been developed which is based on Arbitrary Vortex Flow theory. The software is useful for obtaining initial blade design for the given basic functional requirements in terms of Airflow, Pressure Rise and Speed which defines the operating point of the fan. CFD analysis of the initial fan design is then carried out to predict the fan performance curve. Computation model resembles a fan set up in a wind tunnel. Further, Parametric Optimization is carried out using CFD to meet the functional requirements. A Rapid Prototype sample of the optimized fan design is manufactured and tested in a fan test rig made as per AMCA 210-99 standard to evaluate the fan performance curve and the power consumption.

Automotive clutches form the most important component in the drive line which acts both as torque transmitter and as a fuse. Testing clutches, in the vehicle assembly, poses certain limitations. In this context the automotive clutch, as a component, needs to be evaluated to determine various performance parameters like wear, load loss, slipping torque, slipping time etc. to meet desired design, performance and durability requirements. It is very important to simulate engine and vehicle conditions in terms of operating environment, speed and load accurately while evaluating above parameters. This creates lot of challenges to design and develop a test rig capable of evaluating complete clutch performance. Very limited options are available for such test rigs worldwide. In India, no manufacturer provides such indigenous test rigs. Developing an indigenous, cost effective clutch test rig was the need of the hour.

The Indian automotive industry is striving towards more safe and durable vehicles. A need was felt to study the effect of changes in axle static loads on fatigue life of the axle components. Also, there was a need to develop generic test method, as there are no test standards or generic methods available in public domain for fatigue testing of commercial vehicle axles. The study was carried out to check direct effect of change in axle loads on various connections on axle, effect of suspension configuration and force distribution, Vehicle dynamics, etc. In this paper, an India specific generic load spectra was evaluated for accelerated laboratory validation. Paper discusses the methodology as; study of heavy commercial vehicle systems, road load data collection on identified test vehicles w.r.t. test matrix finalized, India specific test loads and load spectra development, normalization of axle load spectra w.r.t to static axle weights and arriving at test guidelines.

CNG has recently seen increased penetration within the automotive industry. Due to recent sanctions on diesel fuelled vehicles, manufactures have again shifted their attention to natural gas as a suitable alternative. Turbocharging of SI engines has seen widespread application due to its benefit in terms of engine downsizing and increasing engine performance [1]. This paper discusses the methodology involved in development of a multi cylinder turbocharged natural gas engine from an existing diesel engine. Various parameters such as valve timing, intake volume, runner length, etc. were studied using 1D simulation tool GT power and based on their results an optimized configuration was selected and a proto engine was built. Electronic throttle body was used to give better transient performance and emission control. Turbocharger selection and its location plays a critical role.

The Steering system is one of the most safety critical systems in an automobile. With time the durability, reliability and the fine-tuning of the parameters involved in this subsystem have increased along with the competitiveness of the market. In a competitive market, accelerated testing is the key to shorter development cycles. It is observed that the majority of component manufacturers have a preference on vehicle level testing to achieve their development goals. The vehicle level trials are time consuming and lack the control and repeat-ability of a laboratory environment. This paper describes the development of a steering test rig designed to simulate the disturbances experienced on road within a controlled laboratory environment. The five axis steering rig would allow simulation of individual road wheel displacement along with steering wheel angle input and lateral steering rack displacements. The rig also is designed to be adaptable to a range of vehicle categories.

Engine mount is an integral part of any Internal Combustion engine. It is the medium which isolates the vibrations coming from engine being transferred to the chassis or body. Engine or power plant is the main source of unbalanced vibrations. The major role of an engine mount is to reduce those vibration levels, improve ride comfort and increase the life of an engine and its parts [1]. This work determines the Test methodology development for passenger car engine mounts in the Laboratory by using Multi-axial environment [2]. This explains the details of truly Multi-axial test rig development, Drive file creation and the Durability Testing with the maintained vehicle conditions by simulating field conditions in the laboratory. The Multi-axial test rig developed with incorporation of vehicle’s both Front Drive shafts torques and One Propeller shaft which simulates the Front wheel drives and the rear prop shaft torque.

Last decade has been era of environmental awareness. Various programs have launched for making devices and appliances eco-friendly. This initiative has lead automobile industry toward hybridization and now total electrification of vehicles. As electric motor is being added to automobile as a prime mover, due to high frequency vibrations along with higher torque electric motor needs to be isolated properly & carefully as this vibration can damage other automobile parts. Dynamic response of electric motor is different from response of IC engines, so use of engine mounting design method may not be suitable for designing mounting system for electric motor. First, both 4- point and 3- point mounting system are considered for analytical and experimental investigation of force and displacement transmissibility. Position and orientation of elastomeric mounts plays important role in design of mounting system for electric motor.

With introduction of Bharat Stage VI (BS VI) norms from 1st April 2020, automotive industry will observe one of most stringent Indian emission regulation implementation in line with International standards. The Bharat Stage VI (BS VI) regulation also mandates for Real Driving Emission (RDE) measurement from 1st April 2020 for data collection and subsequently establishment of RDE compliance Factor (CF) by 1st April 2023. Indian RDE test procedure will be largely based on European RDE with minor changes in terms of climatic conditions, traffic pattern, speed limit, topography, and vehicle population. For performing a successful RDE trial one of the most critical part is selection of a route on which all RDE boundary conditions can be met. This technical paper summarizes the outcome of RDE experiments carried out on Light Duty Vehicles (LDV) in the city of Pune, Mumbai, and Bangalore. The collected data was post processed using CO2 based Moving Average Window (MAW) method.

Autonomous Emergency Braking (AEB) systems play a critical role in ensuring vehicle safety by detecting potential rear-end collisions and automatically applying brakes to mitigate or prevent accidents. This paper focuses on establishing a framework for the Verification & Validation (V&V) of Advanced Driver Assistance Systems (ADAS) by testing & verifying the functionality of a RADAR-based AEB ECU. A comprehensive V&V approach was adopted, incorporating both virtual and physical testing. For virtual testing, closed-loop Hardware-in-Loop (HIL) simulation technique was employed. The AEB ECU was interfaced with the real-time hardware via CAN. Data for the relevant target such as the target position, velocity etc. was calculated using an ideal RADAR sensor model running on the real-time hardware. The methodology involved conducting a series of test scenarios, including various driving speeds, obstacle types, and braking distances.

Passive safety regulations specify minimum safety performance requirements of vehicle in terms of protecting its occupants and other road users in accident scenarios. Currently for majority cases, the compliance of vehicle design to passive safety regulations is assessed through physical testing. With increased number of products and more comprehensive passive safety requirements, the complexity of certification is getting challenged due to high cost involved in prototype parts and the market pressures for early product introduction through reduced product development timelines. One of the ways for addressing this challenge is to promote CAE based certification of vehicle designs for regulatory compliance. Since accuracy of CAE predictions have improved over a period of time, such an approach is accepted for few regulations like ECE-R 66/01, AIS069 etc which involves only loadings of the structures.

With the recent development in virtual modelling and vehicle simulation technology, many OEM’s worldwide are using digital road profiles in virtual environment for vehicle durability load prediction and virtual design evaluation. For precise simulation results, it is important to have the tire digital twin which is the realistic representation of tire in the virtual environment. The study comprises of discussion about different types of tire models such as empirical, solid model, rigid ring model and flexural ring models such as Pacejka, MF Swift, CD tire, F tire etc. and also the complexity involved in development of these tire models. Generation of virtual tire model requires highly sophisticated test rigs as well as vehicle level testing with Wheel Force transducers and other vehicle dynamics sensors. The large number of data points generated with testing are converted in standard TYDEX format to be further processed in various software tool for virtual model generation.

The term Industry 4.0 is well known in contemporary automotive landscape. It encompasses a smart integrated framework of IIoT (Internet of Things) and industrial automation with machine learning, artificial intelligence and big data analytics to arrive at optimal solutions to running the processes in a streamlined, efficient and effective manner. Industry 4.0 has assumed critical significance in the contemporary era of people working from remote locations to operate processes in order to build products, thereby ensuring business continuity. Consequently, it follows that if industry 4.0 is applied to automotive homologation activity, it will lead to a standardized evaluation, consistent fidelity of testing, accurate judgement of the product under test with regards to its certification, and most importantly, timed delivery to release in the market. The author hereby elucidates a unified Industry 4.0 Framework for Automotive homologation in India which is the need of the hour.

The paper discusses the methodology for measuring the sound absorption of sound package materials in a different sizes of reverberation chambers. The large reverberation chamber is based on test methods and requirements as per ASTM C423 and ISO 354 standards. Both the test standards are similar and recommend a reverberation chamber volume of at least 125 m3 and 200 m3 respectively for sound absorption measurements from 100 Hz to 5000 Hz. The test sample size requirements are from 5.5 to 6.7 m2 as per ASTM C423 and 10 to 12 m2 as per ISO 354. In the automotive sector passenger car, heavy truck, and commercial vehicle, the parts that are used are much smaller in size than the size prescribed in both the standards. The requirement is to study the critical parameters such as the chamber volume, sample size, reverberation time and cut-off frequency etc. which are affecting the sound absorption property of acoustic material.

Front windscreen wiping test is legal requirement for all motor vehicles as per standards like IS15802:2008 [1], IS15804:2008 [2] in India. This test requires windscreen mock-up/actual vehicle to be tested along with all wiping mechanisms such that minimum percentage areas to be wiped should meet the requirements specified in the IS standard. From manufacturer’s perspective this involves investment of lot of time and cost to arrive at the final design solution in order to meet the wiping requirements. The work scope in this paper is limited to bus category of vehicles. The methodology presented in this paper would enable quick design solutions for bus body builders or manufacturers to meet the wiping requirements specified in IS standard. The methodology presented in this paper was developed to carry out windscreen wiping test through commercially available simulation software.

The windscreen wiping system is mandatory requirement for automotive vehicle as per Central motor vehicle rules (CMVR). The main scope of the standard is to ensure vision zones to be wiped by wiping system to ensure maximum field of vision to the driver. The evaluation of vision zones as per IS 15802:2008 is generally determined by virtual simulation by OEMs. The limitation of virtual simulation is due to actual tolerances in vehicle, due to seat fitment, ergonomic dimensions, seat cushioning effect and wiper non-effective operation which are not taken into consideration very well off. The testing methodology described in the paper is an in-house developed test method based on SAE recommended practices. With the help of 3D H-point machine and a laser based ‘Theodolite’ equipped with horizontal and vertical angle projections from single pivot point is used to develop various vision zones on an actual vehicle windscreen as per technical data.