Refine Your Search

Topic

Search Results

Viewing 1 to 18 of 18
Technical Paper

Strength Analysis and Structural Optimization of Lever of Air Disc Brake

2014-09-28
2014-01-2507
Air disc brake (ADB) is the execution unit of automobile brake, which plays a vital role in traffic safety. Lever is a very important driving as well as stress part of ADB. However, seldom periodical or thesis has given specifications about the lever. In this paper, working principle of the lever is illustrated in detail. Finite element analysis (FEA) of the lever is conducted and some structural problems of the lever are found out. Finally, for the condition that the lever doesn't meet the strength requirement, topography optimization is introduced to improve the shape of lever. Simulation results show that the strength of the lever improved obviously with the optimization, and analysis method as well as optimization method in this paper is feasible.
Technical Paper

Analysis of the Thermal Deformation in an Automotive Exhaust-Based Thermoelectric Generator

2015-04-14
2015-01-0348
The potential for automotive exhaust-based thermoelectric generator (TEG) has been increasing with continuously advances in thermoelectric technology. In this paper, the thermal deformation of the TEG system is studied on the basis of the surface temperature distribution of the heat exchanger. The simulation result shows that thermoelectric modules (TMs) on different positions have different thermal performance which can significantly influence the power generation efficiency of the system. Meanwhile, in terms of the working performance of TMs, the clamping mechanism is considered to have some effects on both the cold side and the hot side of TEG. Following the simulation, bench tests are carried out to confirm the reasonability of the simulation results.
Technical Paper

The Finite Element Analysis and Optimization on a Special Vehicle

2015-04-14
2015-01-0473
According to the resonant pavement crusher's work principle, its front frame mounted with the resonance system must meet the needs of the structural requirements. To satisfy the strength and stiffness requirement and avoid the resonance, the natural frequency of the front frame should be designed away from the crusher's working frequency. In this paper, the author builds a finite element model of the front frame and analyses its modal. According to the modal analysis results, the fourth modal frequency is close to the working frequency of the crusher. So the front frame should be optimized. In the finite element model, the front frame has been divided into a number of components of shell elements. Through optimal Latin hypercube experimental design, the author analyses the different component thickness's relationship of the frequencies of the front frame. The components with higher correlation coefficient have been chosen as the variables of optimization.
Technical Paper

Flow Field Analysis and Structure Optimization of the Suction Nozzle for Road Sweeper

2016-04-05
2016-01-1356
As a key component of airstream system equipped in the road sweeper, the structure of the suction nozzle determines its internal flow field distribution, which affects the dust-sucking efficiency to a great degree. This research is aiming to determine a better suction nozzle structure. Starting with an analysis of the one used in a certain type of road sweeper, the initial model of the suction nozzle is established, and the internal flow field is simulated with typical computational fluid dynamics (CFD) software named FLUENT. Based on the simulation results, the dust-sucking capability of the initial structure is evaluated from the aspects of pressure and velocity distribution. Furthermore, in order to explore the influence of different structural parameters on the flow field distribution within the suction nozzle, models with different cavity heights and shoulder angles are established, and Univariate Method is utilized to analyze the contrast models.
Technical Paper

The Topology Optimization Analysis on Rope-Wheel Glass Lifter

2016-04-05
2016-01-1384
Glass lifter is a key part of automobile door system. Guide rail is the carrier of glass lifter, and it bears various load cases when glass lifer works. Mass, stiffness and natural frequencies are the factors that influence the performance of glass lifter. In order to design a lighter and reasonable glass lifter, topology optimization methods are studied in this paper. In a rope-wheel glass lifter, design domain is determined by the mechanical structure and working conditions. Firstly, the single target continuum structure topology optimization mathematic models of guide rail are built in this paper, and analysis of multi-stiffness topology optimization are carried out accordingly in which volume fraction is set as 0.4, 0.5 and 0.6. These models are based on SIMP (Solid Isotropic Material with Penalization) theory.
Technical Paper

Simultaneous Optimization of Power Train Parameter and Control Strategy in a Plug-In Hybrid Electric Bus

2015-09-29
2015-01-2828
In the Plug-in hybrid electric bus, the power train parameter and control strategy significantly affect the economy and dynamic performance. Thus, the simultaneous optimization of power train parameter and control strategy is designed for the trade-off between the dynamic and economic performance. Depending on the parallel electric auxiliary control strategy in a plug-in hybrid electric bus, a vehicle dynamic simulation model is built with the software AVL Cruise. Aiming at the minimization of equivalent gas consumption and acceleration time from 0 to 50kmph, the gear ratio, final drive ratio, gear shifting strategy and control strategy are chosen as optimal variable, which significantly impact power performance and fuel economy. The driving performance and the driving range with full battery are considered as constraints. Based on the software Isight, multi-objective optimization model is built by adopting non-dominated sorting genetic optimization algorithm (NSGA-II).
Technical Paper

Multidisciplinary Design Optimization of BEV Body Structure

2015-01-14
2015-26-0229
Blade Electric Vehicle (BEV) with a light body plays an important role in saving the energy and reducing the exhaust emission. However, reducing the body weight need to meet the heterogeneous attributes such as structural, safety and NVH (Noise, Vibration and Harshness) performance. With the rapid development of finite element (FE) analysis technology, simulation analysis is widely used for researching the complex engineering design problem. Multidisciplinary Design Optimization (MDO) of a BEV body is a challenging but meaningful task in the automotive lightweight. In present research, the MDO is introduced to optimize a BEV Body-in-White (BIW).
Technical Paper

Research on Acoustic Performance of Automotive Exhaust Thermoelectric Generator

2016-04-05
2016-01-0220
With great development of thermoelectric exhaust heat recovery technology, more and more attention has been paid to optimization of automotive thermoelectric generators (ATEGs). A lot of work has been done on optimization of flow field and thermal analysis. However, investigation on acoustic optimization is rather limited. In this paper, efforts have been paid to study the acoustic performance of a flat-plate TEG, and the feasibility of integration of automotive exhaust thermoelectric generator with muffler was discussed. The internal configuration of heat exchanger looks like “fishbone”. Four factors have been taken into consideration: the spacing of two fins, angle of the fins, the diameter of inlet and outlet of exchanger; and filling sound absorbing material in heat exchanger chamber. Based on these four factors, acoustic analysis was carried out.
Technical Paper

Research on Torsional Characteristic of Separate Frame Construction for a Light Off-Road Vehicle

2015-03-10
2015-01-0014
A key problem of designing a light off-road vehicle with separate frame construction is to improve its torsional characteristic, which has a significant influence on the performance of the vehicle. Inevitably, a certain distortion of the body would be produced by the vibration and impact passing from the road. In present research, an analysis model of light off-road vehicle is established based on the theories and methods of finite element (FEM). The static stiffness of the body is simulated and the deformation of openings on the body, mainly the windows and the doors of the vehicle is studied. On the working conditions of torsion and braking combination, torsion and cornering combination, diagonal dangling, ultimate torsion of unilateral wheels and diagonal wheels, the static strength of separate frame construction is studied as well. The stress concentration regions are obtained according to the results of simulation.
Technical Paper

The Application of Superelement Modeling Method in Vehicle Body Dynamics Simulation

2016-09-27
2016-01-8050
In this paper, we propose a method of dynamics simulation and analysis based on superelement modeling to increase the efficiency of dynamics simulation for vehicle body structure. Using this method, a certain multi-purpose vehicle (MPV) body structure was divided into several subsystems, and the modal parameters and frequency response functions of which were obtained through superelement condensation, residual structure solution, and superelement data restoration. The study shows that compared to the traditional modeling method, the computational time for vehicle body modal analysis can be reduced by 6.9% without reducing accuracy; for the purpose of structural optimization, the computational time can be reduced by 87.7% for frequency response analyses of optimizations; consistency between simulation and testing can be achieved on peak frequency points and general trends for the vibration frequency responses of interior front row floors under accelerating conditions.
Technical Paper

Fuel-Efficient Driving for Motor Vehicles Based on Slope Recognition

2017-03-28
2017-01-0037
The drivers' hysteretic perception to surrounding environment will affect vehicular fuel economy, especially for the heavy-duty vehicles driving under complex conditions and long distance in mountainous areas. Unreasonable acceleration or deceleration on the slope will increase the fuel consumption. Improving the performance of the engine and the transmission system has limited energy saving potential, and most fuel-efficient driving assistant systems don't consider the road conditions. The main purpose of this research is to introduce an economic driving scheme with consideration of the prestored slope information in which the vehicle speed in mountainous slopes is reasonably planned to guide the driver's behavior for reduction of the fuel consumption. Economic driving optimization algorithm with low space dimension and fast computation speed is established to plan accurate and real-time economic driving scheme.
Technical Paper

The Research of the Adaptive Front Lighting System Based on GIS and GPS

2017-03-28
2017-01-0041
Automotive Front Lighting System(AFS) can receive the steering signal and the vehicular speed signal to adjust the position of headlamps automatically. AFS will provide drivers more information of front road to protect drivers safe when driving at night. AFS works when there is a steering signal input. However, drivers often need the front road's information before they turn the steering wheel when vehicles are going to go through a sharp corner, AFS will not work in such a situation. This paper studied how to optimize the working time of AFS based on GIS (Geographic Information System) and GPS(Geographic Information System) to solve the problem. This paper analyzed the process of the vehicle is about to go through a corner. Low beams and high beams were discussed respectively.
Technical Paper

The Effect Factors and Location Planning Method Study of a Novel Car-Sharing Network

2017-03-28
2017-01-0249
With the development of the Internet for vehicles, the Car-sharing has been developed rapidly in recent years. This paper focuses on the network programming and distribution for Car-sharing, which helps to clarify the characteristics and basic law of Car-sharing network development, as well as the main approaches to construct it. Firstly, by analyzing the effect factors and expanding ways of Car-sharing network, characteristics of the development of Car-sharing industry and its network, as well as main Car-sharing users and services, the influence factors of Car-sharing demand and the main demand points in a city are summarized. Secondly, in order to better evaluate the network programming and distribution for Car-sharing, this paper proposes an optimization decision method of the car-sharing network planning by evaluating the possible alternatives in a same scale. The assessment index of Car-sharing network planning is constructed.
Technical Paper

Fuzzy Control of Semi-active Air Suspension for Cab Based on Genetic Algorithms

2008-10-07
2008-01-2681
Semi-active suspension has been widely applied in commercial vehicle suspension in order to get good riding comfortableness. Fuzzy logic control (FLC) has been widely applied in the field of kinetic control because control rule of FLC is easy to understand. But the gain of fuzzy rules and adjustment of membership functions usually depend on experts' experiences and repeated experiments, thus the fuzzy rules and membership functions has strong subjectivity, also are easily affected by environment of experiments, so the main problem of fuzzy logic controller design is selection and optimization of fuzzy rules and membership functions. Genetic Algorithms (GA) is the algorithm that searches the optimal solution through simulating natural evolutionary process and is one of the evolution algorithms which have most extensive impact.
Journal Article

Cracking Failure Analysis and Optimization on Exhaust Manifold of Engine with CFD-FEA Coupling

2014-04-01
2014-01-1710
For fracture cracks that occurred in the tight coupling exhaust manifold durability test of a four-cylinder gasoline engine with EGR channel, causes and solutions for fracture failure were found with the help of CFD and FEA numerical simulations. Wall temperature and heat transfer coefficient of the exhaust manifold inside wall were first accurately obtained through the thermal-fluid coupling analysis, then thermal modal and thermoplastic analysis were acquired by using the finite element method, on account of the bolt pretightening force and the contact relationship between flange face and cylinder head. Results showed that the first-order natural frequency did not meet the design requirements, which was the main reason of fatigue fracture. However, when the first-order natural frequency was rising, the delta equivalent plastic strain was increasing quickly as well.
Journal Article

Simulation of Organic Rankine Cycle Power Generation with Exhaust Heat Recovery from a 15 liter Diesel Engine

2015-04-14
2015-01-0339
The performance of an organic Rankine cycle (ORC) that recovers heat from the exhaust of a heavy-duty diesel engine was simulated. The work was an extension of a prior study that simulated the performance of an experimental ORC system developed and tested at Oak Ridge National laboratory (ORNL). The experimental data were used to set model parameters and validate the results of that simulation. For the current study the model was adapted to consider a 15 liter turbocharged engine versus the original 1.9 liter light-duty automotive turbodiesel studied by ORNL. Exhaust flow rate and temperature data for the heavy-duty engine were obtained from Southwest Research Institute (SwRI) for a range of steady-state engine speeds and loads without EGR. Because of the considerably higher exhaust gas flow rates of the heavy-duty engine, relative to the engine tested by ORNL, a different heat exchanger type was considered in order to keep exhaust pressure drop within practical bounds.
Journal Article

Research on Driving Posture Comfort Based on Relation between Drivers' Joint Angles and Joint Torques

2014-04-01
2014-01-0460
Driving comfort is one of the most important indexes for automobile comfort. Driving posture comfort is closely related to the drivers' joint angles and joint torques. In present research, a new method is proposed to identify the most comfortable driving posture based on studying the relation between drivers' joint angles and joint torques. In order to truly reflect a driving situation, the accurate human driving model of 50 percent of the size of Chinese male is established according to the human body database of RAMSIS firstly. Biomechanical model based on accurate human driving model is also developed to analyze and obtain dynamic equations of human driving model by employing Kane method. The joint torque-angle curves of drivers' upper and lower limbs during holding wheel or pedal operation can be obtained through dynamic simulation in the MATLAB. Through curve-fitting analysis, the minimum joint torque of a driver' limb and the optimal joint angel can be found.
Journal Article

Investigation of Deposits in Urea-SCR System Based on Vehicle Road Test

2017-03-14
2017-01-9275
In vehicles with urea-SCR system, normal operation of the urea-SCR system and engine will be influenced if there are deposits appearing on exhaust pipe wall. In this paper, a commercial vehicle is employed to study the influence factors of deposits through the vehicle road test. The results show that, urea injection rate, temperature and flow field have impacts on the formation of deposits. When decreasing the urea injection rate of calibration status by 20%, the deposit yield would reduce by 32%. If the ambient temperature decreased from 36 °C to 26 °C, the deposit yield would increase by 95%. After optimizing the exhaust pipe downstream of the urea injector by removing the step surface, only a few flow marks of urea droplets are observed on the pipe wall, and no lumps of deposits existing.
X