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Technical Paper

Implications of Future Scrap Car Handling for Design of Cars

1996-04-01
91A124
In this paper the socio-economic and technical problems of the handling of car wrecks are discussed. The recovery of metals as a goal for shredder operations will increasingly be supplemented with the recovery of other materials such as polymers. In order to deal economically and technically with polymer materials, it is necessary to know in advance which type of wreck handling will be used. Also optimization of shredder operations allow less freedom to incorporate a variety of materials when compared with selective dismantling or disassemble of cars. It is argued that various technical solutions have to be accompanied by increased cooperation along the firms that are connected to the handling of car wrecks. Cooperation between the scrap context and designers is essential, in order to optimize dismantling practices according to criteria of environmentally preferred solutions.
Technical Paper

Fe Model Adjustment of a Composite Material Car-Body By Means of Experimental Modal Analysis on the Prototype

1996-04-01
91A095
A procedure adopted to verify and update the finite elements model of an electric powered car-body manufactured from composite materials is described. Experimental results, obtained from modal testing of the prototype, are used in order to identify and correct discrepancies in the FE model. The availability of a highly reliable FE model allows to simulate structural modifications by computer, optimizing the use of composites and reducing in the same time at minimum prototypes construction. The approach followed suggests a possible remarkable reduction in product development costs and duration. The work has been performed within a larger program for the development of thermoplastic composite materials, with particular attention to transportation market.
Technical Paper

Package Tray Optimization Using Experimental and Analytical Techniques

1999-05-17
1999-01-1686
The area in the neighborhood of the package tray can be a significant path for road noise and exhaust noise. Air extraction routes and loudspeakers add to the difficulty of effective system design. A variety of designs were prototyped and their transmission loss measured in a standard SAE J1400 sound transmission loss suite. The performance of the various designs was compared to an untrimmed piece of sheet metal with embedded air extraction holes. The addition of trim added from 1 dB to 14 dB to the transmission loss. Statistical energy analysis (SEA) models of a variety of package tray systems will also be shown. Both of these techniques can provide design guidance at an early stage of vehicle program development.
Technical Paper

A Nomograph Approach to Optimized Design of a Compact Spur Gear Set

1999-05-17
1999-01-1717
Computer Aided Design and Optimization are two important directions of present research activity in spur gears. A review of literature indicates that the methods available, are iterative and rather tedious. In present work the non-linear optimization problem with the minimum centre distance as an objective function has been addressed. A new design space in terms of module and pinion number of teeth has been defined. Empirical relations to obtain Feasible Optimal Centre Distance based on input torque and gear ratio for 20° pressure angle for 20 gear materials, obtained by regression analysis, have been reported. A simple nomograph has been developed which gives pinion number of teeth and standard module.
Technical Paper

Vibration Weldability Study for Painted Plastics

1999-05-10
1999-01-1628
Weldability study has been performed on Polypropylene (PP) and PC/ABS samples to investigate how the paint layer along the weld joint affects the vibration weldability. The plastic used for this study were PP representing semicrystalline thermoplastics and PC/ABS representing amorphous thermoplastics. Both resins were molded to generate sample plaques for the study. Design of Experiment (DOE) studies were initially conducted with unpainted plaques and then repeated with the painted plaques for comparison. Optimal welding parameters were determined through DOE and the maximum weld strength under optimized welding conditions were determined and compared. Following each DOE, a regression analysis, using the weld strength as a response, was performed.
Technical Paper

Considerations About Chaotic Dynamics of Exhaust Tube and its Design Optimization in Respect to its Dynamic Properties

1999-05-17
1999-01-1657
Vibration of an exhaust tube with a non-linear fixing construction is analyzed. Numerical and laser holography investigation methods are used for the determination of vibration processes happening nearby the cylinder fixing areas. Obviously, the analyzed non-linear system can produce complex reactions even to harmonic excitations. The knowledge about such zones of “wrong” dynamic behavior may help to eliminate and reduce higher noise levels and extend the lifetime of the construction.
Technical Paper

Intake/ Exhaust Noise Reduction with Rig Test Optimization – Case Studies

1999-05-17
1999-01-1660
The study employed the rig test method for the intake/exhaust noise investigation by using shaker. This article describes two case studies including 1.2 liter minivan and a 250 c.c. motorcycle. For the minivan case, it was verified that along with the reduction of 5∼8 dB(A) of intake noise the interior noise was also improved using the rig test optimization result. For the motorcycle case, It was found that there was very good correlation of the exhaust noise measured among the engine dynamometer, road test and rig test after the temperature effect was compensated. Hence, the study chose the rig test as a development tool to get prompt NVH evaluation results on the different exhaust pipe lengths and keep the development time schedule. From the results, it is concluded that the simple and cheap rig test evaluation technique is vital and a very effective tool to achieve the vehicle NVH development goal.
Technical Paper

Development of a Simple Numerical Method of the Exhaust System to Find Optimized Design Values

1999-05-17
1999-01-1666
During numerical analysis of an exhaust system, the use of shell elements gives accurate results. However, it requires a lot of modeling and calculation time and a big computer system. In this paper, bar elements have been utilized for the numerical analysis of the exhaust system. It shows that the adoption of bar elements providing appropriate results can reduce modeling efforts and computing costs since less than 200 bar elements are enough during the numerical analysis of the exhaust system. To find the equivalent bar properties of curved pipe, the strain energy concept is utilized. The bellows of the exhaust system is simplified with modification of stiffness of bar elements. The developed model can be utilized to find possible hanger position with the analysis of vibration mode. The prediction of endurance performance is another benefit of the developed numerical model with bar elements.
Technical Paper

Numerical Optimization of Ring-Pack Behavior

1999-05-03
1999-01-1521
The ring-pack behavior in a modern gasoline engine represent complicated phenomena. The process of ring pack design consists of two stages: understanding the physical behavior and design synthesis on the systematic manner. Computer models give an inside on the physical processes associated with the ring-pack behavior. Mathematical optimization techniques provide the tools for design synthesis on the systematic way based on an optimal criteria. The mathematical optimization technique was developed and applied to ring pack design synthesis. When applied to the existing engine ring-pack designs, the optimized results indicated the potential for significant reduction in blow-by through the ring-pack by optimizing ring pack geometry. The optimization results were compared with the original ring pack designs for two gasoline engines for a wide range of operating conditions.
Technical Paper

Shoebox Converter Design for Thinwall Ceramic Substrates

1999-05-03
1999-01-1542
Shoebox catalytic converter design to securely mount thinwall substrates with uniform mounting mat Gap Bulk Density (GBD) around the substrate is developed and validated. Computational Fluid Dynamic (CFD) analysis, using heat transfer predictions with and without chemical reaction, allows to carefully select the mounting mat material for the targeted shell skin temperature. CFD analysis enables to design the converter inlet and outlet cones to obtain uniform exhaust gas flow to achieve maximum converter performance and reduce mat erosion. Finite Element Analysis (FEA) is used to design and optimize manufacturing tool geometry and control process. FEA gives insight to simulate the canning process using displacement control to identify and optimize the closing speed and load to achieve uniform mat Gap Bulk Density between the shell and the substrate.
Technical Paper

Improvement of Performance and Exhaust Emissions in a Converted Dual-Fuel Natural Gas Engine

2000-06-19
2000-01-1866
To improve performance and exhaust emissions of a converted dual-fuel natural-gas engine, the effects of basic parameters were experimentally investigated. The results show that diesel fuel operation is favorable at very low loads and that a small amount of pilot fuel with a moderate injection rate is effective for suppressing knock at high loads. As for the charge air throttling, there is an optimal combination of charge amount and equivalence ratio to obtain high thermal efficiency and reduced emissions. An optimal strategy for fueling is demonstrated based on the results. Adequate control of pilot fuel amount, injection timing and throttle opening area gives diesel-equivalent thermal efficiency with very low smoke emission over a wide range of loads.
Technical Paper

Performance Development of the First European Heavy Duty Diesel Engine Equipped with Full Electronic High Injection Pressure Common Rail System

2000-06-19
2000-01-1821
Over the last few years, Renault VI has gained an important knowledge in low emissions combustion optimization using the high injection pressure Common Rail system. A completely new six cylinder in-line DCI 11 engine has been designed with this full electronic injection system for EURO3 truck applications. The engine performance has been optimized to reach low fuel consumption and low emissions, while keeping customer utilization in mind. After a short view on the general features of the new engine, the highly flexible injection system is presented as well as its potential to control fuel injection timing, fuel quantity and pressure with multiple injections, independently of engine speed and load. The development process is described, covering the swirl design with two inlet ports per cylinder, the injector and combustion bowl geometry match and the injection data optimization.
Technical Paper

Graphitic Foam Thermal Management Materials for Electronic Packaging

2000-04-02
2000-01-1576
The goal of this program is to utilize the recently developed high conductivity carbon foam for thermal management in electronics (heat exchangers and heat sinks). The technique used to fabricate the foam produces mesophase pitch-based graphitic foam with extremely high thermal conductivity and an open-celled structure. The thermal properties of the foam have been increased by 79% from 106 to 187 W/m·K at a density of 0.56 g/cm3 through process optimization. It has been demonstrated that when the high-thermal-conductivity graphitic foam is utilized as the core material for the heat exchanger, the effective heat transfer can be increased by at least an order of magnitude compared to traditional designs. A once-through-foam core/aluminum-plated heat exchanger has been fabricated for testing in electronic modules for power inverters.
Technical Paper

Fundamental Physics Behind New Suspension Concept for Automobiles

2000-05-01
2000-01-1647
The Transverse Leaf suspension with Superior Roll Axis is a new suspension concept for automobiles. It enables the load transfer during a turn to be more evenly redistributed between the two wheels on the same axle thus optimizing its tires lateral force capabilities. The TLSRA concept is made up of a single transverse leaf spring linking the middle of the sprung mass to the outer end of 2 transverse suspension arms per axle. Those transverse arms are mounted close to the middle of the sprung mass with their attachment points located above the mass centroïd. Each wheel assembly is mounted directly onto the free end of its respective suspension arm. Because body roll is now counteracting vertical load transfer during transient and permanent operating conditions, this suspension enables designers to keep spring stiffness low without compromising road handling.
Technical Paper

Utilizing a Genetic Algorithm to Optimize Vehicle Simulation Trajectories: Determining Initial Velocity of a Vehicle in Yaw

2000-05-01
2000-01-1616
A method was developed for determining the unknown initial velocity of vehicles in yaw based upon evidence of the vehicle’s trajectory. The problem is formulated as an optimization problem by minimizing the error between a simulation trajectory and the known vehicle trajectory as per tire marks. A search simulation is coded in Matlab. An objective function is formulated based upon the error between the search simulation’ trajectories and the trajectory prescribed by the tire mark evidence. Initial conditions and step driver inputs are the design variables. A genetic algorithm routine coded in Matlab, GAOT (Genetic Algorithm Optimization Toolbox), is implemented to determine the solution vector that results in a simulation trajectory that minimizes the objective function. Target simulations are created using EDVSM (Engineering Dynamics Vehicle Simulation Model). The optimization algorithm is implemented and errors in the resultant velocities are reported.
Technical Paper

The Use of Chemiluminescence for the Ranking of Lubricants in Terms of Oxidation Stability

2000-06-19
2000-01-1812
In this study, a chemiluminescence apparatus (CL), ATLAS CL–400, was employed to measure the oxidation induction time (OIT) of various types of lubricants. Results of OIT obtained for base oils and industrial oils were compared to that obtained from standardized methods requiring larger expenditures of sample and/or analysis time. Some exploratory tests were also run on engine oils having increased expected performance. The technique was found to be very good for the ranking of lubricants since the relative oxidation stability of the products studied has been successfully evaluated by chemiluminescence (CL). This method was shown to be a good tool for oil formulation optimization.
Technical Paper

New Electronically-Controlled Trolling System for Marine Gear

1999-09-28
1999-01-3262
A marine gear is a reversible reduction gear provided in an inboard engine typically used as a propulsion unit for fishing boats. One of its functions is to provide “trolling speed” to make the boat go very slow. Some devices to attain the trolling speed is already available, in which hydraulic oil pressure for clutch coupling is mechanically controlled to achieve the boat's slow speed. However, conventional device is not satisfactory in view of performance and operational handiness. The new control system reported here resolves such problem by utilizing a solenoid to achieve optimal control over the hydraulic oil pressure. It assures easy handling, and provides the most desirable performance for a fishing boat to go dead slow. The system has an additional function to deal with another concern about a marine gear, that is, the rattling noise of the driving gear which often occurs while the engine is running in the low speed range.
Technical Paper

Increase of Flow Rate of Super - Mini Sac Nozzle and its Application for General Use Small Engine

1999-09-28
1999-01-3263
Reacent strict emisssion regulation requires inprovement in the contradictory turget, that is to say, more engine power per displacement and less pollutants. This target could be realized ZEXEL by increasing the allowable injection quantity in the nozzle with a smaller sac volume, and increasing the flow rate of nozzle hole without enlarging the nozzle orifice size. Sac volume of the super-mini sac nozzle is dereased to 0.17mm3, from 0.23-0.31 mm3 which is the minimum level of the conventional mini sac nozzle. Increase in injection flow rate was obtained by means of the “Extrude Horn” treatment which makes round and smooth both inner surface of the sac and the entrance edge of the orifice. The trade-off between NOx, HC emissions and the combustion noise was improved by optimizing the injection rate in low speed and low load range.
Technical Paper

Research on the Performance of a Waterjet Propulsor for Personal Watercrafts

1999-09-28
1999-01-3264
A waterjet propulsor has come to be used more popularly for high speed watercrafts such as personal watercrafts. The most difficult problem for designing the waterjet system is that a tradeoff is required to properly determine the best parameters for the waterjet pump and subsequently the best overall propulsion system. This paper presents the design method and performance improvement of the waterjet propulsor used for personal watercrafts. The authors have clarified the performance of the individual component in the waterjet propulsor and improved the component efficiency empirically, and established the method to estimate the thrust and power characteristics of the propulsor on board from the component test results and other design parameters, which enables the optimization of the waterjet system.
Technical Paper

A Study of Direct Fuel Injection Two-Stroke Engine for High Specific Power Output and High Engine Speed

1999-09-28
1999-01-3288
High specific power output two-stroke engine for snowmobile use was converted to a Direct Fuel Injection (DFI) engine, in order to achieve lower HC emission by avoiding fuel short circuiting and to obtain higher specific power output by increasing induction air and optimizing A/F. High pressure single fluid fuel system was chosen because of extremely high fuel delivery rate. The fuel injector and its location were investigated and optimized for better mixture formation and lower HC emission. 140kW/L level specific power output, maximum engine speed of 9000 rpm, and 1/2 the level of HC emissions were obtained.
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