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Electric Vehicle is the need of an hour, as due to excessive usage of IC Engine vehicles has resulted in the depletion of the ozone layer to a significant level and fuel cost is increasing. With new technologies coming into the market, challenges come hand in hand because of Electric Vehicle. In comparison to IC Vehicle, areas of thermal management or the number of components for which thermal management needs to be done is higher and rather complex. As the thermal management system is the second highest energy consuming source after the powertrain of the electric vehicle, an efficient and reliable design is mandatory to ensure better range in an Electric Vehicle. Thermal Management of the Electric Vehicle has been identified as one of the critical parameters for balancing both cabin comfort as well as Battery temperature. One of the major concerns is meeting the Cabin comfort during colder weather with minimum energy consumption.

Model based calibration is extensively used by the automotive OEMs (Original Equipment manufacturers) because of its correlation accuracy with test data and freezing the operating parameters such as injection timings, EGR rates, fuel quantity etc. The prediction of Brake specific Fuel consumption (BSFC), Exhaust and intake temperatures are very close to test data. The prediction of Brake specific NOx is directionally reliable with acceptable tolerance.

Light weighting is an effective strategy in increasing energy efficiency in the automotive industry. In this paper, mass reduction with cost benefit was targeted in an exterior trim panel. Polypropylene copolymer (PPCP) compound was developed for a large exterior trim panel (1400 X 700mm) having an integrated grill mesh. The part had challenging requirements in terms of slow speed impact, structural durability, dimensional stability, aesthetics, thermal ageing resistance, cold impact resistance, scratch resistance and weathering resistance. By having ultra-high flow behavior, optimum tensile strength, modulus, impact strength and thermal properties, the PPCP compound met the requirements for a thin wall exterior trim panel with a thickness of 2.6mm. Structural durability of the design was validated by virtual engineering. Part design and material combinations with better tooling design iterations were analyzed by using mold flow analysis.

This paper discusses design and optimization process for the integration of exhaust manifold with turbocharger for a 3 cylinder diesel engine, simulation activities (CAE and CFD), and validation of manifold while upgrading to meet current BS6 emissions. Exhaust after-treatment system needs to be upgraded from a simple DOC (Diesel Oxidation Catalyst) to a complex DOC+sDPF (Selective catalytic reduction coated on Diesel Particulate Filter) to meet the BS6 emission norms for this engine. To avoid thermal losses and achieve a faster light-off temperature in the catalyst, the exhaust after-treatment (EATS) system needs to be placed close to the engine - exactly at the outlet of the turbocharger. This has given to challenges in packaging the EATS. The turbocharger in case of BS4 is placed near the 2nd cylinder of the engine, but this position will not allow placing the BS6 EATS.

During the vehicle launch (i.e. moving the vehicle from “0” speed), the clutch would be slowly engaged by the Driver or Transmission Control Unit (in Automatic Transmission/Automatic Manual Transmission vehicle) for smooth torque transfer between engine and transmission. The clutch is designed to transfer max engine torque with min heat generation. During the clutch engagement, the difference in flywheel and gearbox input shaft speed is called the clutch slipping phase which then leads to a huge amount of energy being dissipated in terms heat due to friction. As a result, clutch surface temperature increases consistently, when the surface temperature crosses the threshold limit, the clutch wears out quickly or burns spontaneously. Hence it is crucial to predict the energy dissipation and temperature variation in various components of clutch assembly through virtual simulation.

Till recently supercharging was the most accepted technique for boost solution in gasoline engines. Recent advents in turbochargers introduced turbocharging technology into gasoline engines. Turbocharging of gasoline engines has helped in powertrains with higher power density and less overall weight. Along with the advantages in performance, new challenges arise, both in terms of thermal management as well as overall acoustic performance of powertrains. The study focuses mainly on NVH aspects of turbocharging of gasoline engines. Compressor surge is a most common phenomenon in turbochargers. As the operating point on the compressor map moves closer to the surge line, the compressor starts to generate noise. The amplitude and frequency of the noise depends on the proximity of the operating point to the surge line. The severity of noise can be reduced by selecting a turbocharger with enough compressor surge margin.

Aesthetics contribute significantly to the customer’s buying decision of an automobile. This is traditionally achieved through painting. Sustainability and cost challenges have led automakers to look at substituting painting through molded-in color polymers in decorative bezels like pillar appliques. These appliques and bezels have a unique mix of material requirements that include color tone, gloss, stiffness, scratch resistance and weathering. Polycarbonates are an interesting class of polymers that has the potential to meet these challenging requirements. This paper reports the work done in evaluating a polycarbonate compound in piano black shade to meet the functional and aesthetic requirements. The results prove that the material can substitute painting thereby resulting in significant cost savings. This is a ready to mold material used in injection molding process. This modified polycarbonate material has been explored for thin wall appliques and bezels with thickness of 2.7 mm.

The present work discusses the developed simulation model aimed to predict the heat rejection (HR) performance and external pressure drop characteristics of automotive charge air cooler (CAC). Heat rejection and airside pressure drop characteristics of CAC were predicted for the conditions of different charge air mass flow rates and different cooling air velocities. The lack of detailed research on CAC performance prediction has motivated the development of the proposed simulation model. The present 1-D simulation has been developed based on the signal library of AMESIM application tool. Input parameters for this simulation such as core size, tube pitch, tube height, number of tubes, fin density, louver angle, louver pitch, charge air mass flow rate, cooling air velocity, charge air inlet temperature, and ambient temperature. Heat rejection curve and airside pressure drop of CAC were the output of the present simulation.

This paper discusses the methodology setup for grill opening area prediction at the early development phase of the product development lifecycle, using a commercially available 1D simulation tool- AMESIM. Representative under hood has been modeled using Grill, Condenser, Radiator, intercooler, fan, and engine components. Vehicle velocity is used as an input to derive the airflow passing through the grill and other under-hood components based on ram air coefficient, pressure drop through different components (Grill, Heat exchanger, Fan & Engine). This airflow is used to predict the top tank temperature of the radiator. Derived airflow is correlated with airflow obtained from CFD simulation. A balance has been achieved between cooling drag & fan power consumption at different grill opening areas for target top tank temperature. Top tank temperature has been predicted at two different extreme engine heat rejection operating points.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. The engine cooling system plays a vital role in meeting the stringent emission norms and improving the vehicle fuel economy apart from maintaining the operating temperature of engine. The airflow through vehicle subsystems like the grille, bumper, the heat exchangers, the fan and shroud and engine bay are called as front-end flow. Front end flow is crucial factor in engine cooling system as well as in determining the aerodynamic drag of vehicle. The airflow through the engine compartment is determined by the front-end vehicle geometry, the CRFM and CAC package, the engine back restriction and the engine compartment geometry including the inlet and outlet sections. This paper discusses the 1D modelling method for front-end airflow rate prediction and thermal performance by 1D method. The underbody components are stacked using heat stack and simulated in pressure mode.

The Indian automotive industry has migrated from BS IV (Bharat stage IV) to BS VI (Bharat Stage VI) emission norms from 1st April 2020. This two-step migration of the emission regulations from BS IV to BS VI demands significant engineering efforts to design and integrate highly complex exhaust after-treatment system (EATS). In the present work, the methodology used to evaluate the EATS of a high power-density 1.5-liter diesel engine is discussed in detail. The EATS assembly of the engine consists of a diesel oxidation catalyst (DOC), a diesel particulate filter with selective catalytic reduction coating (sDPF), urea dosing module and urea mixer. Typically, all these components that are needed for emission control are integrated into a single canning of shell thickness ~1.5mm. Moreover, the complete EATS is directly mounted onto the engine with suitable mounting brackets on the cylinder block and cylinder head.

Major focus was given on the Comfort, Fuel efficiency & Safety during the development of the passenger cars, which certainly drives the vehicle business of Original Equipment Manufacturer (OEM’s). The air Conditioning in a car, plays an important role in the area of comfort of the passengers and fuel efficiency point of view. Especially Heat Exchanger plays a pivotal role in the air conditioning system. So, it’s a challenge for the OEM’s to select and design the optimal heat exchanger from the supplier, which meets the performance and packaging requirements during the design phase of the product development cycle. The objective of this paper to focus on analytical calculation or framework was developed using an excel tool considering the effect of variable geometry of fin which includes louver pitch, louver angle and louver length in a multi-pass condenser. Further, this theoretical calculation was validated using experimental data and CFD simulation.

In today’s automobile industry where BS6 emission is posing a high challenge for aggregate development, cost control and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and to meet the challenging engineering requirement. Thus, the frugal engineering comes into the picture. This paper shows the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other.

In this paper, mold in color diamond white ASA material has been explored for front bumper grill, fender arch extension, claddings and hinge cover applications. Other than aesthetic requirements, these parts have precise fitment requirement under sun load condition in real world usage profile. Structural durability of the design was validated by virtual engineering. Part design and material combinations with better tooling design iterations were analyzed by using mold flow analysis. Complete product performances were validated for predefined key test metrics such as structural durability, thermal aging, cold impact, scratch resistance, and weathering criteria. This part met required specification. This mold in color ASA material-based parts has various benefits such as environmentally friendly manufacturing by eliminating environmental issues of coating, easily recycled, and faster part production because intended color achieved in one step during molding.

Application of advance composites in place of the various conventional materials such as steel can give significant weight and performance advantages. The application of composites is now finding it’s way in the automotive industry due to the growing requirement of the lightweight solutions and high strength to weight ratio. However, their low mechanical properties have limited their application in automotive structural components. The study presented here is focused on the explicit dynamic analysis of a bumper beam and advance composites are used for the study. Different configurations and designs of the bumper are considered to be able to make a comparative study of the stress and deformation levels. The analysis was done in coherence to the Euro NCAP tests and the offset frontal impact analysis was done. The boundary conditions were aligned with the real time impact conditions for proper prediction of the results.

The spoiler is functional as well as aesthetic part fitted on the vehicles to improve the vehicle aerodynamic performance and better aesthetic appeal. The improvement of aerodynamics performance of the vehicle at higher speeds is achieved by reducing the overall vehicle coefficient of drag. This helps in better handling and improved fuel efficiency of the vehicle thus contributing to development of greener vehicle. In this project, our main focus is to reduce overall vehicle coefficient of drag, Design a light weight spoiler and improve the vehicle aesthetic appearance.

In any industry, early detection and mitigation of a failure in component is vital for feasible design changes or development iterations or saving money. So it becomes pivotal to capture the failure mode in an accelerated way. This theory poses many challenges in devising the methodology to validate the failure mode. In real world, vehicle head lamp is exposed to all possible kinds of harsh environments such as variable daily ambient, rain, dust and engine compartment temperature …etc. This brings rapid thermal stress onto headlamp resulting into warpage cracks. At vehicle level on particular model, this failure is typically observed after 20,000-25,000 kms in a span of 3-4 months of running. Any corrective action to revalidate the design change or improvement will need similar timelines in regular way to test, which is quite high in product development cycle.

Wind noise is becoming important for automotive development due to significant reductions in road and engine noise. This aerodynamic noise is dominant at highway speeds and contributes towards higher frequency noise (>250Hz). In automotive industry accurate prediction and control of noise sources results in improved customer satisfaction. The aerodynamic noise prediction and vehicle component design optimization is generally executed through very expensive wind tunnel testing. Even with the recent advances in the computational power, predicting the flow induced noise sources is still a challenging and computationally expensive problem. A typical case of fluid-solid interaction at higher speeds results into broadband noise and it is inherently an unsteady phenomenon. To capture such a broad range of frequency, Detached Eddy Simulation (DES) has been proven to be the most practical and fairly accurate technique as sighted in literature.

Piston is a critical component of the engine as it exposed to high inertial and thermal loads. With the advent of high performance engines, the requirement of the piston to perform in extreme conditions have become quintessential. Piston scuffing is a common engine problem where there is a significant material loss at the piston and the liner, which could drastically affect the performance and the longevity of the components. This detrimental phenomenon would occur if the piston is not properly designed taking into consideration the thermal and structural intricacies of the engine. A water-cooled gasoline engine which had significant wear pattern on its piston skirt and liner was considered for this study. The engine block was made of aluminum alloy with a cast iron sleeve acting as liner. The piston-liner system was simulated through a commercially available numerical code which could capture the piston's primary and secondary motion.

As automobiles become increasingly quieter, the wiper operation noise becomes more noticeable by the customer. This paper deals with the experimental approach and the methodology to investigate the Friction induced wiping noise. Role of design in a wiper system plays a very imperative task in meeting the performance of wipers but at the same time it does not cater to the NVH issues. Some of the important design parameters which affect the NVH properties of the wiper system are highlighted in this paper. For better understanding of the system some of the best in class vehicles for SUV category were tested and compared with our test vehicle. In this study more importance given to analytical part which is more important to investigate and in depth study of the friction induced noise. For analytical study some techniques such as time frequency domain i.e. Wavelet transforms, frequency domain and time domain where extensively used.