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Recently, Hybrid electric vehicles have become significant. Electric vehicle is still in its infancy while grappling with multiple solutions to its problem of range anxiety and heavy weight. It makes HEV the viable and intermediate solution which can facilitate the transition. The battery behaviour is grossly defined by its dependence on variation due to temperature change. Hence, this present work focuses on understanding thermal characterization & pure behaviour of the Li-Ion Phosphate (LiFePO4) P1-HEV battery using the HPPC test. This becomes imperative because of the varying driver demands and ambient temperatures over the use during the day. Thus, the current drawn from battery varies (different C rate) leading to heat generation (I2R heating) within the pack/individual cell. Cyclically, impacting the cell performance and battery cycle life.

In present scenario, tyre industry is more focused on providing maximum extent of NVH comfort to passengers by improvising the tyre design. Noise contribution from the tyres is classified in to three regions, viz., structure-borne (tyre vibrations), air-borne (tread pattern) and cavity noise (air cavity). In general, a Finite Element (FE) model of tyre provides an inherent advantage of analyzing tyre dynamic behavior. In this paper, an attempt was made to develop a three-dimensional FE tyre model and validate the same through experimental approach. The CAD Model of the tyre was generated through 3D image scanning process. Material property extraction of tyre was carried out by Universal Testing Machine (UTM) to generate Finite Element (FE) model. For validation of tyre FE model, Experimental Modal Analysis (EMA) and Noise Transfer Function (NTF) were conducted.

To enhance the crashworthiness of electric vehicles, designing the optimized and safer battery pack is very essential. The deformed battery cell can result in catastrophic events like thermal runaway and thus it becomes crucial to study the mechanical response of battery cell. The goal of the research is to experimentally investigate the effect of mechanical deformation on Lithium-ion battery cell. The paper thoroughly studies the phenomenon of short circuiting at the time of failure. Various experiments are carried on 18650 cylindrical cells (NCA chemistry) under custom designed fume hood. The setup captures the failure modes of battery cell. The loading conditions have been designed considering the very possible physical conditions during crash event. The study has been done for radial compression, semicircular indentation, hemispherical indentation, flat circular indentation and case of three-point bending.

NVH has gained importance in the field of earth moving equipment due to the demand of quieter machines and stringent in-cab as well as exterior noise emission norms. Several parts of the world have adopted strict legislation on noise emission by earth moving equipment, but many countries have not adopted any regulations till date. The aim of this study is to help governing bodies as well as machine manufacturers in adopting simple yet accurate testing method for compactor machine. The study consists of directivity analysis, noise source identification, noise source ranking and 4-point microphone position sound power evaluation method applied to compactors with wide range of engine power ratings. All the tests in 4-point method and directivity analysis were performed under stationary as well as dynamic conditions.

The Electric Vehicles (EV) or Hybrid Electric Vehicle (HEV) has a bunch of electrical/electronic components and its operation give rise to complicated EMI/EMC issues. The Power Electronics Module (PEM), comprising of DC-DC convertor/invertor and Battery Management Unit (BMU), is driving the motor to propel the vehicle. “Battery Pack Module” powers these units through cables. The fast switching of these circuit elements present in the system leads to noise propagation through the cables. These noise signals give rise to various Electromagnetic (EM) related issues in the cable harness of vehicle. It is essential that these cables should not interfere with other electronic components and also does not get effected by external EM disturbances.

Electric Vehicles (EVs), with its inherent advantage of zero tailpipe emissions, are gaining importance because of aggressive push from government not only to reduce air pollution but also to reduce dependency of fossil fuel. EVs and necessary charging infrastructure along with ‘connected’ technology is redefining mobility. Considering the fast growing EV market, it becomes important for an EV Powertrain Architect to design and develop a powertrain solution having low engineering efforts and satisfying business, market and regulatory requirements at a competitive price. This paper presents a compact, flexible, convenient and smart featured simulation tool for an EV Powertrain Architect for estimating the specifications of key powertrain components such as traction battery and electric motor. The proposed tool takes into consideration the end-user as well as the regulatory requirements of range, maximum speed, acceleration and gradeability.

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.

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.

Sound Quality (SQ) of brake and clutch pedal assembly plays an important role in contributing to vehicle interior noise and perception of sound. Quiet operation of brake and clutch units also reflects the vehicle built and material quality. Noise emitted from these sub-assemblies has to meet certain acceptance criteria as per different OEM requirements. Not much work has been carried on this over the years to characterize and quantify the same. An attempt has been made in this paper to study the sound quality of brake and clutch pedal assemblies at component level and validate the same by identifying the parameters affecting SQ. Effect on noise at different environmental conditions was studied with typical operating cycles in a hemi-anechoic chamber. The effect of sensor switches integrated within the clutch and brake pedal on sound quality is analyzed. It is found that the operating characteristics of switches drives the noise and SQ.

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 use of Hybrid Electric Vehicles (HEV) will become imperative to meet the emission challenges. HEV have two power sources-fossil fuels driven I.C. Engine and the battery based drive. Battery technologies have seen a tremendous development, and therefore HEV’s have been benefited. Even as the battery capacities have improved, maintaining and monitoring their health has been a challenge. This research paper uses open-source platform to build a BMS. The flexibility in the implementation of the system has helped in the rapid prototyping of the system. The BMS system was evaluated on a scaled-down electric toy car for its performance and sustainability. The BMS was evaluated for reverse polarity, protection against overcharge, short-circuit, deep discharge and overload on lead acid battery. It also includes temperature monitoring of the batteries. This proposed system is evaluated on the in-house HEV two-wheeler. The initial results are promising.

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.

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.

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.

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.

Autonomous vehicles perform various functions with their own control strategies. Functions like Lane Departure Warning (LDW), Lane Keeping system (LKS) and Forward Collision Warning System (FCWS) requires special test tracks for their verification and validation. These test track requirements change with region to region according to available infrastructure. This paper deals with the design and development of test tracks for different ADAS functions verification and validation of Indian specific scenarios and its simulation in IPG CarMaker. The test track conceptualization has been done through the understanding and study of different international standards and geometry of test tracks for Indian conditions have been developed. IPG CarMaker software tool is used for creation of test track, and same track is used for simulation of above ADAS functions in IPG CarMaker.

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.

The technology development in automobiles is progressing towards providing smarter vehicles with increased efficiency and reduced emission. To cater this need, Electric Vehicles (EV) and Hybrid Electric Vehicles (HEV) are slowly thriving in Indian roads. Conversion of existing IC engine powered vehicle to HEV reduces complication in new vehicle development and also results in vehicles with increased efficiency and reduced emission. In order to convert the Conventional Vehicle to Hybrid Electric Vehicle, drive from electric motor was coupled with existing driveline by modifying mechanical systems suitably. Hybrid vehicle includes systems such as electric motors, inverters, high-voltage batteries and electronic control units, which are mounted in chassis members. Being a major load carrying member, any modifications in chassis system may affect the performance of vehicle, therefore it is necessary to evaluate the modified design of chassis members.

Role of wheel and underbody aerodynamics of vehicle in the formation of drag forces is detrimental to the fuel (energy) consumption during the course of operation at high velocities. This paper deals with the CFD simulation of the flow around the wheels of a bus with different wheel housing arrangements. Based on benchmarking, a model of a bus is selected and analysis is performed. The aerodynamic drag coefficient is obtained and turbulence around wheels is observed using ANSYS Fluent CFD simulation for different combinations of wheel-housing- at the front wheels, at the rear wheels and both in the front and rear wheels. The drag force is recorded and corresponding influence on energy consumption of a bus is evaluated mathematically. A comparison is drawn between energy consumption of bus body without wheel housing and bus body with wheel housing. The result shows a significant reduction in drag coefficient and fuel consumption.

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%.