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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.

Connected vehicle services have come a long way from the early days of telematics, both in terms of breadth of the class of vehicles, and in terms of richness or complexity of the data being handled for Enhancing Customer Experience. The Connectivity Control unit (CCU) is a gateway device for the vehicle to the outside world. While it enables transmission of vehicle data along with the location information. CCU is currently validated in the vehicle to check functionality. It has cost, time drawbacks and prevents effective testing of many scenarios. Bench level validation will not be able to complete functionality validation. There is subset of validation tools or semi-automated solutions are available in the market, but they are not fully functional, and critically cannot perform end to end validation. Automated Test setup for CCU in lab simulating the entire field data of the vehicle with modifiable characteristics.

In the era of fierce competition, launching a defect free product on time would be the key to success. In a modern automobile, the transmission system is designed with utmost care in order to transfer the maximum power from engine to driveline smoothly and efficiently. Optimized design of all the transmission components is necessary in order to meet the power requirement with the least possible weight. This optimization may require gear designs with different internal diameters. The assembly of these gears may not be possible on a solid transmission shaft. To facilitate assembling while retaining optimum design of transmission parts, a separate bush is designed to overcome this limitation. Some bushes may require a flange to restrict any free play of the mounted gear in its axial direction. During complete system level testing of one newly developed manual transmission, bush failure was observed.

There is a higher demand for quieter tractors in the agri-industry, as the continued exposure to noise levels have disastrous effects on operator’s health. To meet the world-wide regulatory norms and to be the global market leader, its mandatory to develop the comfortable tractor which meets homologation requirements and customer expectations. Typically, Operator Ear Level (OEL) noise has been evaluated in the test, after First Proto has been made. This approach increases cost associated with product development due to late changes of modifications and testing trails causing delay in time-to-market aspect. Hence, there is a need to develop the methodology for Predicting tractor OEL noise in virtual environment and propose changes at early stage of product development. At first, full vehicle comprising of skid, sheet metals and Intake-exhaust systems modelled has been built using Finite Element (FE) Preprocessor.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. Even if there is a slight reduction in product cost and time has a high significant impact on business. Engineers are under tremendous pressure to develop competitive and give better product concern resolution at the earliest. To arrest the failure of this thermostat vent, an innovative approach was used to relocate de-aeration restrictor on the hose to the thermostat root. Thus, resolving the product concern by increasing the strength of the vent at root and providing good business impact on cost savings. Physical testing has provided an effective way to smoothen product development for concern resolution. This Paper highlights approach on an attempt to field failure simulation with existing and modified design with lab test results.

This paper explains the methodology to design a high power-density diesel engine capable of 180 bar peak firing pressure yet achieving the lowest level of mechanical friction. The base engine architecture consists of an 8 mm crank-offset which is an optimized value to have the lowest piston side forces. The honing specification is changed from a standard plateau honing to an improved torque plate slide honing with optimized surface finish values. The cumulative tangential force of the piston rings is reduced to an extreme value of 28.5 N. A rectangular special coated top ring and a low-friction architecture oil ring are used to reduce the friction without increasing the blow-by and oil consumption. A special low-friction coating is applied on the piston skirt in addition to the optimized skirt profile to have reduced contact pressure. The piston pin is coated with diamond-like carbon (DLC) coating to have the lowest friction.

The ever-increasing customer expectations put a lot of pressure on car manufacturers to constantly reduce the noise, vibration, and harshness (NVH) levels. This paper presents the holistic approach used to achieve best-in-class NVH levels in a modern high-power density 1.5 lit 4-cylinder diesel engine. In order to define the NVH targets for the engine, global benchmark engines were analysed with similar cubic capacity, power density, number of cylinders and charging system. Moreover, a benchmark diesel engine (considered as best-in-class in NVH) was measured in a semi-anechoic chamber to define the engine-level NVH targets of the new engine. The architecture selection and design of all the critical components were done giving due consideration to NVH behaviour while keeping a check on the weight and cost.

Child injury performance evaluation is becoming critical part of almost all legal and consumer ratings-based vehicle safety evaluation protocols. Most of New CAR Assessment Programs (NCAP) now have separate ratings exclusively to evaluate child restraint system effectiveness and child dummy performance under various crash testing modes. OEM’s have need and challenge to maximize injury performance. Sled tests are conventionally used for tuning restraints like seat belts and airbags for driver and co-driver under various frontal type test conditions. However, second row seats are used for CRS/ Child injury performance evaluations. In the present study an attempt is made to simulate child injury performance of P3 dummy positioned on second row seat on defined child seat for 64 kmph frontal Offset deformable barrier type test conforming to Global NCAP. Sled pulses are carefully tuned to capture key injury patterns. Thence restraint parameters are tuned to improve child dummy injuries

Structural durability of different components and systems for a Utility Vehicle is critical to design, due to severe customer usage in rural zones and off road driving conditions. Physical validation of new component designs is time consuming, costly and iterative. Also, this process does not ensure an optimized structure. Through virtual validation it is possible in the initial phase of design to validate the structure and optimize the design. The core of a virtual validation process is to obtain accurate correlation which can replace developmental laboratory testing. Hence, only a confirmatory test can be carried out. This enables design optimization based on simulations. This paper presents the systematic approach used for optimization of SUV rear bumper and bumper mounting structure. Dynamic correlation is obtained for bumper structure subjected to the vibration levels as mapped from the proving ground test. The objective of new bumper development is for value engineering.

Reducing the vibrations in the powertrain is one of the prime necessities in today's automobiles from NVH and strength perspectives. The necessity of 4×4 powertrain is increasing for better control on normal road and off-road vehicles. This leads to bulky powertrains. The vehicle speeds are increasing, that requires engines to run at higher speeds. Also to save on material costs and improve on fuel economy there is a need for optimizing the mass of the engine/vehicle. The reduced stiffness and higher speeds lead to increased noise and vibrations. One more challenge a powertrain design engineer has to face during design of its transmission housings is the bending / torsional mode vibrations of powertrain assembly. This aggravates other concerns such as shift lever vibrations, shift lever rattle, rise in in-cab noise, generation of boom noise at certain speeds, etc. Hence, reducing vibrations becomes an important and difficult aspect in design of an automobile.

This paper describes application of Design of Experiments (DOE) technique and optimization for mass reduction of a Sports utility vehicle (SUV) body in white (BIW). Thickness of the body panels is taken as design variable for the study. The BIW global torsion, bending and front end modes are key indicators of the stiffness and mass of the structure. By considering the global modes the structural strength of the vehicle also gets accounted, since the vehicle is subjected to bending and twisting moments during proving ground test. The DOE is setup in a virtual environment and the results for different configurations are obtained through simulations. The results obtained from the DOE exercise are used to check the sensitivity of the panels. The panels are selected for mass reduction based on the analysis of the results. This final configuration is further evaluated for determining the stiffness and strength of the BIW.

The ECE R-14, AIS015 safety standard specifies the requirements of the safety belt anchorages namely, minimum numbers, their locations, static strength to reduce the possibility of their failure during accidental crashes for effective occupant restraint and the test procedures. This standard applies to the anchorages of safety belts for adult occupants of forward facing or rearward facing seats in vehicles of categories M and N. ECE R14 ensures the passenger safety during sudden acceleration/retardation and accidents. Early simulations revealed some structural short falls that demanded cabin improvements in order to fulfill regulation requirements for the seal belt anchorage test. This paper describes the innovative design modifications done to meet the seat belt anchorage test. Good correlation with the test is achieved in terms of deformations. These simulation methods helped in reducing the number of intermediate physical tests during the design process.

Globally the customers are demanding more powerful yet silent vehicles to enhance their daily commuting and goods transportation needs. The current trend in the design is to enhance the engine power without major change in the physical configurations of the engine systems. Increasing the power and torque of the powertrain will have an undesirable and adverse effect on NVH levels. In this research work, a light weight rear wheel drive vehicle was investigated from torsional vibration perspective. The vehicle is powered by a two cylinder engine with turbo charger. The power and torque of the vehicle was increased approximately two times with the help of turbocharger which resulted in increasing the powertrain torsional vibration. This increased vibration was further amplified through inevitable driveline resonances which causes severe vibration at the passenger seat location and steering. Also, the noise levels are above the comfortable zone.

Over the ages of automotive history, expectations of the customers increases vastly starting from driving comfort, better fuel economy and a safe vehicle. Requirement of good vehicle drivability from customers are increasing without any compromise of fuel economy and vehicle features. To enhance the product, it is a must for every OEM’s to have better drivability to fulfill the needs of the customer. This paper explains Objective Drivability Evaluation done on compact SUV vehicle and comparison with subjective drivability. Vehicle manufacturer usually evaluate drivability based on the subjective assessments of experienced test drivers with a sequence of certain maneuvers. In this study, we have used the objective drivability assessment tool AVL drive to obtain the vehicle drivability rating. The vehicle inputs from the accelerometer sensor which captures the longitudinal acceleration and CAN bus signals such as engine speed, vehicle speed, accelerator pedal, are fed into the software.

Twist beam is a type of suspension system that is based on an H or C shaped member typically used as a rear suspension system in small and medium sized cars. The front of the H member is connected to the body through rubber bushings and the rear portion carries the stub axle assembly. Suspension systems are usually subjected to multi-axial loads in service viz. vertical, longitudinal and lateral in the descending order of magnitude. Lab tests primarily include the roll durability of the twist beam wherein both the trailing arms are in out of phase and a lateral load test. Other tests involve testing the twist beam at the vehicle level either in multi-channel road simulators or driving the vehicle on the test tracks. This is highly time consuming and requires a full vehicle and longer product development time. Limited information is available in the fatigue life comparison of multi-axial loading vs pure roll or lateral load tests.

This paper deals with setting of Inspection parameters for selected automotive transmission parts in various bench tests. This paper we are discuss about critical dimension's measured for particular type of test. It is not possible to measure all the dimensions of a component for doing a particular test. This is due to time constraints set by program delivery deadlines. From above statement it can be deduced that it is almost impossible to measure all dimensions of a component. A bench level test may consist of two major tests. They are maximum load test and gear shift durability test. The maximum load test deals with gear box durability test and torque carrying capacity of gearbox. Parameters to be measured for some of above parts will be identified. More importantly it will also identify see reasons for that parameter to be measured.

Gear shift quality and feel determines the performance of the transmission. It is dependent on the synchronizer, shift system, gear shifter etc in a transmission. In this study the impact of the transmission shifter on the gear shift feel is detailed. More focus is paid towards the feel in terms of NVH characteristics. The rear wheel drive transmission shifter can be bifurcated into direct and indirect shift type. Indirect shifter are of two types, the rod type shifter and the cable shifter. The rod type shifter is analyzed in detail. All the shifters are connected to the gear shift top lever which is the customer interface for gear shifting. The design of the top lever is critical in getting the optimal feel of shifting and the mounting of the shifter is critical to improve its NVH characteristics. Different design iteration of the top lever are studied to illustrate the impact of the weight and stiffness on the vibration.

Accurate quantification of structure borne noise is a challenging task for NVH engineers. The structural excitation sources of vibration and noise such as powertrain and suspension are connected to the passenger compartment by means of elastomer mounts and spring elements. The indirect force estimation methods such as complex dynamic stiffness method and matrix inversion method are being used to overcome the limitations of direct measurement. In many practical applications, the data pertaining to load dependent dynamic stiffness of the connections especially related to mounts is not available throughout the frequency range of interest which limits the application of complex dynamic stiffness method. The matrix inversion method mainly suffers from the drawback that it needs operational data not contaminated by the effect of other forces which are not considered for calculation.