Refine Your Search

Topic

Author

Search Results

Technical Paper

Thermodynamic Analysis of Turbocharger for a High Power Density Diesel Engine

2019-01-09
2019-26-0051
Passenger cars claim their presence in market by its pick up, top speed and maximum power of the engine. The study described in this paper is focused on improving the low-end performance of a 4-cylinder 1.6 L diesel engine while meeting the targeted maximum power. To meet the cause turbocharger works as an important element of the engine. A comparative study between regulated two stage turbocharger (R2S) and variable geometry turbocharger (VGT) shows that on a 4-cylinder engine VGT is superior by providing higher boost at 1000 engine rpm full load, than R2S, while in 3-cylinder (same displacement) the opposite effect can be seen. After simulations and iterations, it was confirmed that the in 4-cylinder the exhaust pulse cancellation were leading to a lesser exhaust energy at the turbine inlet. This pulse interaction leads to higher residual gas content which affects the low-end performance.
Technical Paper

Determination of Principal Variables for Prediction of Fuel Economy using Principal Component Analysis

2019-01-09
2019-26-0359
The complexity of Urban driving conditions and the human behavior introduces undesired variabilities while establishing Fuel economy for a vehicle. These variabilities pose a great challenge while trying to determine that single figure for assessment of vehicle’s fuel efficiency on an urban driving cycle. This becomes even more challenging when two or more vehicles are simultaneously evaluated with respect to a reference vehicle. The attempt to fit a generalized linear model, between Fuel Economy as predicted variable and components of a driving cycle as predictor variables produced oxymoronic and counter-institutive results. This is primarily due to existence of multi-collinearity among the predictor variables. The context of the study is to consider the event of driving on a cycle as a random sampling experiment. The outcome of a driving cycle is summarized into a list of predictor variables or components.
Journal Article

A Simulation Approach for Identification and Design Optimization to Prevent Headrest Rattle

2019-01-09
2019-26-0190
Squeak and rattle concerns account for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are a major quality concern for automotive OEM’s. Seat is one of the major contributors of squeak and rattle issues observed in customer verbatim. Seat head rest rod and bezel are designed concentric to each other with a gap that allows free movement and a locking pin to position at different levels. Due to the design gap and weight of the head rest there is always tendency for relative displacement leading to rattle issues. Seat headrest, is close to the customer ear and any rattles at headrest will create annoying driving experience. Also, the contradictory requirements between efforts and rattle makes the scenario more difficult to fine tune the bezel specifications. The root cause for head rest rattle issues can also be related to free play between bezel and seat frame, free play between bezel and cap, looseness between locking pin and headrest rod etc.
Technical Paper

Optimization of Oil Separation Unit for Two Stage Turbocharged Engine

2018-07-09
2018-28-0066
In addition to performance target, recent stringent emission legislation and reduction in oil consumption are the major driving force for engine design and development. In this reference importance of crankcase ventilation has increased immensely and the manufacturers are bound to develop most efficient system with high oil trap efficiency. In crankcase ventilation system, the blow-by gases from the crankcase are routed to the intake manifold through Oil separator system. The oil separator task is to retain the oil part from the blow by gas and send it back to sump. Developing an oil separator for the engine studied here was very challenging considering double stage turbocharger which produces very fine mist of oil and is difficult to separate. The study shows that oil mist coming in blow by is of size 0.3 micron and lesser than it. The major contribution of these fine mists was from turbocharger.
Technical Paper

Comparative Studies of Different VGT Designs on Performance and Smoke of CRDe Engine

2018-07-09
2018-28-0074
Diesel engines have occupied a significant position in passenger car applications in the present automotive sector. Turbochargers find a very prominent role in diesel engines of all applications in order to achieve desired power and better fuel economy. Gaining higher torque at lower engine speeds with low smoke levels is a very tough task with fixed geometry turbochargers due to availability of lower air mass resulting in higher smoke emissions. Variable geometry turbochargers are capable of providing better torque at lower speeds and reduced smoke emissions on Common Rail Diesel engines. The Variable Geometry Turbocharger types used in this study are straight profile nozzle vanes (sample A) and curved profile nozzle vanes (sample B). The curved profile vanes as seen in sample B results in reduced variation of circumferential pressure distortions.
Technical Paper

A Disciplined Approach to Minimize Rattle Issues in Automotive Glove Box Assembly

2018-06-13
2018-01-1481
Nowadays, perception of automotive quality plays a crucial role in customer decision of vehicle purchase. Hence, automotive OEM’s are now working on the philosophy of “Quality Sound”. Out of all the Noise, Vibration & Harshness (NVH) issues identified in a vehicle, the ranking of Buzz, Squeak & Rattle (BSR) stands high and glove box rattle is one of the issues that is continuously observed in all customer verbatim. Specific issues like lid rattle and latch rattle are predominant and gets worse over mileage accumulation. Also minimizing BSR issues in glove box is difficult due to complex latch mechanism. While deciding the bump stop specifications more weightage is given to efforts. The bump stop is selected in a way as not to increase the glove box opening and closing efforts, but the selected bump stops will not provide enough preload to glove box lid leading to rattle issues.
Technical Paper

Vehicle Interior Space Optimization through Occupant Seating Layout Apportioning

2017-07-10
2017-28-1923
Digital human models (DHM) have greatly enhanced design for the automotive environment. The major advantage of the DHMs today is their ability to quickly test a broad range of the population within specific design parameters. The need to create expensive prototypes and run time consuming clinics can be significantly reduced. However, while the anthropometric databases within these models are comprehensive, the ability to position the manikin’s posture is limited and needs lot of optimization. This study enhances the occupant postures and their seating positions, in all instances the occupant was instructed to adjust to the vehicle parameters so they were in their most comfortable position. While all the Occupants are accommodated to their respective positions which finally can be stacked up for space assessments. This paper aims at simulating those scenarios for different percentiles / population which will further aid in decision making for critical parameters.
Technical Paper

Low Rolling Resistance Tires and Their Impact on Electric Vehicles

2017-07-10
2017-28-1941
This paper details the methodology used to show the importance of Low rolling resistance tires in Electric Vehicles. Fuel efficiency and range is paramount with most of the electric vehicle buyers. Although many people are now becoming aware of low rolling resistance tires but its development started way back in 1990’s. It is always challenging to achieve low rolling resistance in smaller tires of size 12 inch or 13 inch along meeting the other critical vehicle parameters such as ride and handling, NVH, durability and many more. The reduction in rolling resistance can also affect the traction properties of tires. In case of very low rolling resistance tires the traction will be very less but it can badly affect the other vehicle parameters. Selection of tires further depend upon the RWUP (Real World Usage Profile). It means the vehicle is targeted for which region and what is the condition of roads there.
Technical Paper

Assessment of Cabin Leakage on Thermal Comfort and Fuel Efficiency of an SUV

2016-04-05
2016-01-0259
The main function of an air conditioning system in a vehicle is to provide the thermal comfort to the occupant at minimum possible energy consumption in all environmental conditions. To ensure the best possible thermal comfort, air conditioning system is optimized on various parameters like heat load, air flow distribution, glass area, trim quality, insulations and cabin leak rate. A minimum cabin leakage is regulatory requirements to ensure the air quality of cabin. Anything above the minimum cabin leak rate ultimately turn into reduced thermal comfort and additional energy consumption. The additional energy consumption to maintain the required thermal comfort in the cabin due to cabin leakage affects the fuel efficiency severely. In the present study, the effect of cabin leakage on fuel efficiency and thermal comfort is studied in details by varying the cabin leakage through mechanical means. The experiments are carried out in normal environmental condition and road condition.
Technical Paper

Cost and Weight Efficient Differential Housing for Off-Road Vehicles

2016-02-01
2016-28-0133
Differential in Gear Box play vital role in Tractors for assisting it in turning and also to take straight path. Light weight machine always have advantage in terms of fuel economy and performance. Weight optimized rotating part have additional benefits of saving power loss, against stationary dead weight. Differential Housing is such a part, which rotates during the vehicle motion and torque transmission. [1] This paper describes a method by which weight of the Differential Housing is optimized. In this particular body of work, additional constraints of avoiding any change in existing cold forged parts like Bevel Gear & Pinion. This also have additional benefit of enhanced flow of Oil inside Differential Housing for better lubrication of Bevel Gears and Pinion. This resulted in weight saving of Differential Housing and finally fuel economy of Tractor.
Technical Paper

New Simulation Methodology for Improved Visual Interaction between Physical Test and CAE in Seat Anchorage Test

2016-02-01
2016-28-0226
For effective occupant protection, automotive vehicle structure needs to be developed for seat anchorage test to prevent the failure of seat anchorages during high speed impacts. Seat anchorages (SA) certification test is mandatory for M & N category vehicles in India. Conventional way of testing automotive vehicle structures for seat anchorage test is using deceleration sled with the help of bungee ropes. Deceleration pulse generated from the physical test is used as a loading input in the current CAE process. With the current CAE method, final deformation of the vehicle structure looks similar to physical test, however, the vehicle visual interactions differ significantly during the deformation event. In the current study, a modified loading methodology is proposed to match both the final deformation as well as vehicle visual interactions. Loading and boundary conditions of physical test were understood in detail with the help of simple free body diagrams.
Technical Paper

Optimizing OSRVM Package for Maximizing In-vehicle Visibility

2015-09-29
2015-01-2837
Overall in-vehicle visibility is considered as a key safety parameter essentially mandated due to the increasing traffic scenario as seen in developing countries. Driver side bottom corner visibility is one such parameter primarily defined by A-pillar bottom and outside rear-view mirror (OSRVM). While defining the OSRVM package requirements such as size, position and regulatory aspects, it is also vital to consider other influencing parameters such as position of pillars, waist-line height, and Instrument panel which affect the in-vehicle visibility. This study explains the various package considerations, methods to optimize OSRVM position, shape and housing design in order to maximize the in-vehicle visibility considering the road and traffic conditions. A detailed study on in-vehicle visibility impacted by OSRVM packaging explained and had been verified for the results.
Technical Paper

Optimization of Vehicle Electrical Energy Consumption

2015-09-29
2015-01-2882
This paper focuses on optimizing the electrical energy consumption of vehicle. By introduction three concepts. 1) Innovative speed control logic for radiator fan motor according to vehicle speed and air flow through radiator. 2) Introducing regeneration of energy from radiator fan motor while free running and deceleration of vehicle. 3) Using BLDC motors (generation mode and motoring mode) in radiator and blower motors. About 50 % of total electrical energy consumption of vehicle is contributed by radiator fan motor and blower motor (proven data by performing alternator charge balance test during NEDC cycle). By introducing above three concepts, 50 % electrical energy consumption can be reduced to 25 - 30 %, which gives more than 3.5 % fuel economy improvement and more than 10 gmCO2 reduction per kilometer. Further reduction in conducted emission at motor level, soft starting for radiator fan and blower motor and elimination of high inrush current.
Journal Article

An Experimental Study of Turbocharged Hydrogen Fuelled Internal Combustion Engine

2015-01-14
2015-26-0051
Hydrogen is considered as one of the potential alternate fuel and when compared to other alternate fuels like CNG, LPG, Ethanol etc., it has unique properties due to absence of carbon. In the current work, Hydrogen engine of 2.5 L, four cylinder, spark ignited Turbocharged-Intercooled engine is developed for Mini Bus application. Multi-point fuel injection system is used for injecting the hydrogen in the intake manifold. Initially, boost simulation is performed to select the optimum compression ratio and turbocharger. The literature review has shown that in-order to get the minimum NOx emissions Hydrogen engines must be operated between equivalence ratios ranging from 0.5 to 0.6. In the present study, full throttle performance is conducted mainly with the above equivalence ratio range with minimum advance for Maximum Brake Torque (MBT) ignition timing. At each operating point, the performance, emissions and combustion parameters are recorded and analyzed in detail.
Technical Paper

Computational and Experimental Investigations to Improve Performance, Emissions and Fuel Efficiency of a Single Cylinder Diesel Engine

2015-01-14
2015-26-0099
From International Energy Statistics (IES) survey, China, US and India are top three countries in emitting CO2 emissions. Further, worldwide national governments are focused to control CO2 emissions at source by stringent regulatory limits. OEMs and Research laboratories are working on several technology options such as advanced fuel injection system, optimizing in cylinder combustion system, thermal management and reduced engine friction to meet this legal requirements. In this paper, research work focused on improving combustion system through selection optimum bowl geometry and increasing volumetric efficiency through valve timings, profile and intake system using both 1D and 3D-CFD numerical approach. The main objective of this approach to utilize fossil fuel to its maximum potential in a single cylinder Naturally Aspirated (NA) water cooled engine with CRDI.
Technical Paper

High Performance EGR Cooler Selection and its Fouling Behavior for a HSDI Diesel Engine

2015-01-14
2015-26-0087
Selection of EGR system is very complex for a particular engine application. The performance of the EGR system depends highly on the Cooler Heat Transfer Efficiency. Cooler effectiveness drops over a period of operation due to soot deposition, HC condensation, and fuel quality. This phenomenon is called as Cooler Fouling. Fouling cannot be avoided completely but the level of performance drop over time has to be studied and minimized. The minimum pressure drop and the highest efficiency in fouled condition is the target for selection of a cooler. In this study, various parameter combinations like tube shape and profile, tube length, number of tubes, tube diameter, and pitch of corrugations, which influence the cooler performance were tested. A better understanding of each of its effect on cooler effectiveness and fouling behavior was obtained. The tube shape was changed from rectangular to circular, also from smooth surface to corrugate.
Technical Paper

Design For Affordability -Composite Running Board

2015-01-14
2015-26-0070
Light weighting is the Current trends in automotive to achieve better fuel economy which helps for meeting fuel economy standards & to offset the higher fuel prices. Thus there is a need to develop composite running board which is light weight & structurally sound enough to meet the performance. The present paper provides a composite running board assembly for an automobile. The running board assembly includes a board, an insert body and a plurality of brackets. Upon stepping of a passenger on the board, the board transfers load on the insert body which subsequently transfers the load to the plurality of brackets thus facilitating even distribution of the load on the automobile body. This paper also put lights on the use of improved TRIZ application - an approach to inventive problem solving for designing highly affordable & light weight running board. The cost & weight reduction achieved with innovative design is about 40 % & 35 % comparing to existing cost & weight.
Technical Paper

Diagnosis and Elimination of Disc Brake Groan in a Utility Vehicle

2014-04-01
2014-01-0043
Brake groan noise is resolved without any major change in the design of brake system and vehicle sub-system components in the development phase of a utility vehicle. The groan noise is observed during the end of the stopping of the vehicle under moderate braking. The concerned NVH issue is perceived as unacceptable noise in the passenger compartment. Groan induced vibration is subjectively felt on steering and seat frame. A typical process is established to successfully reproduce the groan which helped in precisely evaluating the effect of modifications proposed. The temperature range of the disc which has the highest probability to produce the groan noise is found out experimentally. The transfer path analysis is carried out to find the path contributions from suspension. Acoustic transfer functions from considered paths are measured with the suspension removed from vehicle.
Technical Paper

Interior Lighting Harmony

2013-11-27
2013-01-2820
Automotive exterior lighting systems has several regulatory requirements & most of the manufactures have defined internal standards to achieve desired expectations based on vehicle category. Unavailability of such requirements for interior light illuminating systems has motivated the authors to generate test specifications & measurement methodology. There has been growing interest in automotive vehicle interior lighting for both functional and aesthetic requirements. The purpose of this study is to evaluate the Interior light illuminating devices in terms of “Light harmony”. The lighting harmony is “Maintain the color combination and light intensity level within users comfort zone”. In this study the lighting harmony is measured by means of two methods; one is Subjective evaluation & other is Objective evaluation.
Technical Paper

Development & Customization of Test Cases for Start-stop Functionality to Achieve On-road Robustness

2013-11-27
2013-01-2875
The Micro-hybrid technology otherwise called as stop start system offers a significant improvement in fuel economy particularly in urban driving conditions, where more often the engine idles unnecessarily at traffic signals/jams. Micro-hybrid technology stops the engine at traffic signals/jams and starts the engine automatically on clearance of traffic signals/jams leading to reduced fuel consumption and emissions. This is achieved by monitoring several vehicle and engine parameters through appropriate sensing elements. In this study, the system architecture and functional definitions of start/stop system is defined. Equivalence class, boundary value and decision-table testing are used to generate test cases. On generation of test cases, their relevance on on-road robustness and scope for optimization towards time/efforts are analyzed. In the process, a matrix of different conditions and criteria are formulated. Under these conditions, the system behavior is evaluated.
X