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Viewing 211 to 240 of 4707
2016-04-05
Journal Article
2016-01-0404
Qianqian Du
Abstract Crashworthiness is one of the most important performances of vehicles, and the front rails are the main crash energy absorption parts during the frontal crashing process. In this paper, the front rail was simplified to a thin-walled beam with a cross section of single-hat which was made of steel and aluminum. And the two boards of it were connected by riveting without rivets. In order to optimize its crashworthiness, the thickness (t), radius (R) and the rivet spacing (d) were selected as three design variables, and its specific energy absorption was the objective while the average impact force was the constraint. Considering the error of manufacturing and measurements, the parameters σs and Et of the steel were selected as the uncertainty variables to improve the design reliability. The algorithm IP-GA and the approximate model-RBF (Radial Basis Function) were applied in this nonlinear uncertainty optimization.
2016-04-05
Technical Paper
2016-01-0406
Akihiko Asami, Tomoyuki Imanishi, Yukio Okazaki, Tomohiro Ono, Kenichi Tetsuka
Abstract High-tensile steel plates and lightweight aluminum are being employed as materials in order to achieve weight savings in automotive subframe. Closed-section structures are also in general use today in order to efficiently increase parts stiffness in comparison to open sections. Aluminum hollow-cast subframe have also been brought into practical use. Hollow-cast subframe are manufactured using sand cores in gravity die casting (GDC) or low-pressure die casting (LPDC) processes. Using these manufacturing methods, it is difficult to reduce product thickness, and the limitations of the methods therefore make the achievement of weight reductions a challenge. The research discussed in this paper developed a lightweight, hollow subframe technology employing high-pressure die casting (HPDC), a method well-suited to reducing wall thickness, as the manufacturing method. Hollow-casting using HPDC was developed as a method of forming water jackets for water-cooled automotive engines.
2016-04-05
Journal Article
2016-01-0407
Da-Zhi Wang, Guang-Jun Cao, Chang Qi, Yong Sun, Shu Yang, Yu Du
Abstract The increasing demand for lightweight design of the whole vehicle has raised critical weight reduction targets for crash components such as front rails without deteriorating their crash performances. To this end the last few years have witnessed a huge growth in vehicle body structures featuring hybrid materials including steel and aluminum alloys. In this work, a type of tapered tailor-welded tube (TTWT) made of steel and aluminum alloy hybrid materials was proposed to maximize the specific energy absorption (SEA) and to minimize the peak crushing force (PCF) in an oblique crash scenario. The hybrid tube was found to be more robust than the single material tubes under oblique impacts using validated finite element (FE) models. Compared with the aluminum alloy tube and the steel tube, the hybrid tube can increase the SEA by 46.3% and 86.7%, respectively, under an impact angle of 30°.
2016-04-05
Technical Paper
2016-01-0652
Ravi Ranjan, Lakshmaiah Brahmasani, Parvej Khan
Abstract This paper reports a study on Charge air cooler effectiveness, Air intake pressure drop, Acceleration Performance and Rise over ambient temperature of a utility vehicle for different layouts of Inter cooler, radiator, condenser and fan module in order to finalize an efficient Power train cooling system layout. The main objective is effective utilization of front end opening area, eliminating inter cooler heat load on the radiator, so that radiator size, fan size and fan motor wattage can be optimized to achieve desired cooling performance requirements with the cooling system (CRFM) module. Effect of the intercooler effectiveness, Intake pressure drop, Vehicle acceleration performance and Rise over ambient temperature are studied and both the advantages and disadvantages of the proposals are discussed to finalize the better position of inter-cooler along with other engine cooling components.
2016-04-05
Technical Paper
2016-01-1473
Orion P. Keifer, Bradley Reckamp, Charles Moody, Anthony Timpanaro
Abstract Evaluation of the severity of low speed motor vehicle crashes has been the subject of significant research for more than 25 years. These crashes typically result in little if any damage to the vehicles involved and therefore the ability to determine the threshold of damage would be very useful in analysis of such cases. One such threshold, which has been used by accident reconstructionists, is the manufacturer’s published bumper rating in compliance with Federal Motor Vehicle Safety Standards (FMVSS) for vehicle bumpers. The rationale is that if there is any damage to the bumper system of the vehicle in question, the impact must have had a severity greater than the rated bumper speed. This paper examines the FMVSS bumper standards upon which the published bumper ratings are reportedly in compliance, historical low speed testing damage results, and engineering considerations of bumper damage in low speed impacts.
2016-04-05
Technical Paper
2016-01-1471
Anthony Timpanaro, Charles Moody, Wesley Richardson, Bradley Reckamp, Orion Keifer
Abstract It is well known that older vehicles’ headlight assemblies degrade with exposure to the elements and can become cloudy or crazed. It is also known that the degradation decreases the amount of useful light projected forward, which can drastically reduce night time or down-road visibility. Testing has been performed to measure the available light projected by old degraded headlamp assemblies and new replacement assemblies, to quantify the decrease in emitted light caused by the degradation. The work has been extended to quantify the improvement in available light when the degraded lenses are treated with commercially available restoration products. Five different vehicle headlamp assemblies representing four different manufacturers were tested measuring the illumination at a given distance with a modified Extech® illuminance meter.
2016-04-05
Technical Paper
2016-01-1510
Chinmoy Pal, Tomosaburo Okabe, Kulothungan Vimalathithan, Jeyabharath Manoharan, Pratapnaidu Vallabhaneni, Munenori Shinada, Kazuto Sato
Abstract Many active safety systems are being developed with the intent of protecting pedestrians namely; pedestrian airbags, active hood, active emergency braking (AEB), etc. Effectiveness of such protection system relies on the efficiency of the sensing systems. The pop-uphood system was developed to help reduce pedestrian head injuries. A pop-up system is expected to make full deployment of the hood before the pedestrian’s head could hit the hood. The system should have the capability to detect most road users ranging from a six year old (6YO) child to a large male. To test the sensing system, an impactor model (PDI-2) was developed. Sensor response varies for vehicles with different front end profile dimensions.
2016-04-05
Technical Paper
2016-01-1508
Gernot Pauer, Michal Kriska, Andreas Hirzer
Abstract Active bonnet safety systems are implemented into vehicles, to fulfill pedestrian head impact requirements despite little available deformation space. For such systems it is necessary to consider a variety of aspects already from the very beginning of the vehicle design process and the functionality of the whole system needs to be continually cross-checked throughout the whole design process. Many of these aspects are already supported by finite element (FE) methods from vehicle manufacturers and in this paper it is shown, how the last missing links within the development process, the optimization of pedestrian detection sensor signals can also be efficiently supported by FE simulation. The modeling and validation of a pressure tube based sensor system and so called “misuse objects” are demonstrated.
2016-04-05
Technical Paper
2016-01-1266
Shinichi Urabe, Kazutaka Kimura, Yuki Kudo, Akinori Sato
Abstract Solar and other green energy technologies are attracting attention as a means of helping to address global warming caused by CO2 and other emission gases. Countries, factories, and individual homes around the world have already introduced photovoltaic energy power sources, a trend that is likely to increase in the future. Electric vehicles powered from photovoltaic energy systems can help decrease the CO2 emmissions caused by vehicles. Unlike vehicles used for solar car racing, it is not easy to equip conventional vehicles with solar modules because the available area for module installation is very small to maintain cabin space, and the body lines of conventional vehicles are also usually slightly rounded. These factors decrease the performance of photovoltaic energy systems and prevent sufficient electric power generation. This research aimed to estimate the effectiveness of a solar module power generating system equipped on a conventional car, the Toyota Prius PHV.
2016-04-05
Technical Paper
2016-01-1332
Fredrik Henriksson, Kerstin Johansen
Abstract In the automotive industry, mass reduction and lightweight design is a continuing trend that does not show signs of declining. When looking at where to reduce weight in a vehicle, the body is a preferential subsystem due to its large contribution to overall mass and the stability of body composition over a specific model range. The automotive industry of today moves toward a greater differentiation in materials that compose a car, which can be seen in the several different multi material vehicle bodies that have been introduced by manufacturers in recent years. But while mixing materials may contribute to a good compromise between weight reduction and vehicle cost, it also proposes a number of challenges that need to be addressed. Among other material factors, the different coefficients of thermal expansions might introduce new stresses during painting and curing.
2016-04-05
Technical Paper
2016-01-1331
Shingo Hanano, Kanehiro Nagata, Yusuke Murase
Abstract The need to add more color variations to the traditional black gloss has increased globally in recent years. The intention is for automobile manufacturers to differentiate their products in terms of appearance design. The most noticeable trend is to add embellishment around the front grill. The same trend can be seen in the areas around vehicle doors. It is most common to use a coating material to emphasize the black gloss. However, in overseas countries it is a challenge to meet the required appearance quality, and under the current circumstances CKD is imported from Japan to meet such requirements. Recently, a new film-transfer technique has been established that can express black gloss as well as any coating material by transferring the roughness of the film surface. It is achieved by crimping the PET film onto the vinyl-chloride surface after the extrusion molding is performed. Moreover, we have successfully localized this technique and reduced the manufacturing cost.
2016-04-05
Technical Paper
2016-01-1330
Lei Shi, Peng Yi, Zhan Zhang
Abstract The body joint stiffness plays an important role in achieving vehicle attribute targets. One of the major drawbacks of joint stiffness evaluation is the lack of a rigorous criterion to assess whether the stiffness is proper for a body structure. This paper presents a general joint stiffness metric based on Hooke's law to better evaluate the stiffness of a body joint. A strategy for target setting of body joint stiffness was developed for vehicle body design. Finally, a vehicle body example was presented to demonstrate the proposed methodology.
2016-04-05
Technical Paper
2016-01-1329
Fulin Wei, Yanhua Shen, Tao Xu
Abstract Off-road dump truck body is exposed to abrasive wear during handling of granular materials. The wear rate of body of dump truck has direct influence on maintenance and replacement during its service process. In this paper the discrete element method (DEM) is used to simulate the granular materials of dump truck. The wear of body floor during one dumping process can be achieved by cosimulation of FEM-DEM. The wear depth variation of body has the stochastic characteristic which can be modeled by Geometric Brownian Motion (GBM). The two parameters in the stochastic differential equation, drift coefficient and diffusion coefficient, can be estimated by the wear depth measuring data. It is possible to quantitatively predict the wear evolution of every grid point of the body floor by solving this stochastic differential equation. The simulation result of the wear model is helpful to optimize design of off-road dump truck body.
2016-04-05
Technical Paper
2016-01-1335
Abhishek Sinha, Kamlesh Yadav, Rajdeep Singh Khurana
Abstract The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. Working on global platform is challenging in order to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and, at the same time, to meet the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper: a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space.
2016-04-05
Journal Article
2016-01-1334
Christopher Flegel, Parth Bhivate, Liang Li, Yash Mathur, Sanket Phalgaonkar, Mark Benton, Prasanth Muralidharan, Johnell Brooks, Srikanth Pilla, Paul Venhovens, David Lewis, Garrett DeBry, Craig Payne
Abstract The Deep Orange framework is an integral part of the graduate automotive engineering education at Clemson University International Center for Automotive Research (CU-ICAR). The initiative was developed to immerse students into the world of an OEM. For the 6th generation of Deep Orange, the goal was to develop an urban utility/activity vehicle for the year 2020. The objective of this paper is to describe the development of a multimaterial lightweight Body-in-White (BiW) structure to support an all-electric powertrain combined with an interior package that maximizes volume to enable a variety of interior configurations and activities for Generation Z users. AutoPacific data were first examined to define personas on the basis of their demographics and psychographics.
2016-04-05
Technical Paper
2016-01-1328
Praneeth Kurisetty, Naveen Sukumar, Umashanker Gupta
Abstract To compete with the current market trends, there is always a need to develop cost effective frame designs to meet the needs of the customer. During the development of new vehicles, the major focus is on weight reduction, so as to improve the load carrying capacity and fuel efficiency. Due to the introduction of new high strength materials, the static strength conditions can be met by the use of thinner frames, but the dynamic behavior of the frame deteriorates. The dynamic behaviors like ride and handling, comfort are affected by the stiffness of the vehicle frame. The stiffness of the frame is majorly defined by its vertical stiffness, lateral stiffness and torsional stiffness. The vertical stiffness of the frame plays major role in isolating road vibrations to frame mounted aggregates. The lateral stiffness plays a very important role in the handling of the vehicle and cornering ability of the vehicle.
2016-04-05
Technical Paper
2016-01-1349
Siddharth Bhupendra Unadkat, Suhas Kangde, Mahalingesh Burkul, Mahesh Badireddy
Abstract In the current scenario, the major thrust is to simulate the customer usage pattern and lab test using virtual simulation methods. Going ahead, prime importance will be to reduce the number of soft tool prototype for all tests which can be predicted in CAE. Automotive door slam test is significantly complex in terms of prediction through simulation. Current work focuses on simulating the slam event and deriving load histories at different mounting locations through dynamic analysis using LSDyna. These extracted load histories are applied to trimmed door Nastran model and modal transient analysis is performed to find the transient stress history. This approach has a significant advantage of less computation time and stress-convergence with Nastran for performing multiple design iterations compared to LSDyna. Good failure correlation is achieved with the test using this approach.
2016-04-05
Technical Paper
2016-01-1351
Simhachalam Bade
Abstract Aluminum alloys are widely used in the transportation because of their high strength-to-weight ratio and outstanding capability in absorbing energy. In this paper, performance of bumper with crash tubes using aluminum alloy AA7003 materials is compared with that of AA6061 and high strength steel (DP800) using numerical methods. Quasi-static test is simulated using the LS-DYNA implicit finite element program. Bumper and crash tubes are included in the finite element model. Symmetric Holes are provided in the crash tubes to initiate crushing. The energy absorbed by bumper and crash tubes are compared. Dynamic simulation is done using LS-Dyna explicit program. True stress-true plastic strain curves at different strain rates from the literature is used in the dynamic simulation of AA7003 material to study the strain rate effects on impact behavior of tubes. The impact mass is represented by RigidWall Planar Moving Force option in LSDYNA.
2016-04-05
Journal Article
2016-01-1338
Syed F. Haider, Zissimos Mourelatos
Abstract Weight reduction is very important in automotive design because of stringent demand on fuel economy. Structural optimization of dynamic systems using finite element (FE) analysis plays an important role in reducing weight while simultaneously delivering a product that meets all functional requirements for durability, crash and NVH. With advancing computer technology, the demand for solving large FE models has grown. Optimization is however costly due to repeated full-order analyses. Reanalysis methods can be used in structural vibrations to reduce the analysis cost from repeated eigenvalue analyses for both deterministic and probabilistic problems. Several reanalysis techniques have been introduced over the years including Parametric Reduced Order Modeling (PROM), Combined Approximations (CA) and the Epsilon algorithm, among others.
2016-04-05
Technical Paper
2016-01-1339
Piyush Bubna, Marc Wiseman
Abstract OEMs are investigating opportunities to reduce vehicle mass, driven by a need to meet upcoming CAFE targets, increase the range and reduce battery size of EVs. A number of lightweight materials including high strength steels, aluminum alloys, plastics and composites are now in production. To facilitate development of corporate R&D and commercialization plans for new materials, it is beneficial to understand the current manufacturing costs for production components, and their impact on piece price at different volumes. This paper investigates design and cost impact of light-weighting with respect to front door and floor assembly of Toyota Corolla and BMW i3. Toyota Corolla has a traditional steel body and is sold in high volumes while BMW i3 has relatively low annual sales and is primarily made of composite, aluminum and plastic parts.
2016-04-05
Technical Paper
2016-01-1365
Siddharth Bhupendra Unadkat, Suhas Kangde, Mahalingesh Burkul, Mahesh Badireddy
Abstract The overall automotive industry is moving toward first time right test which in turn needs first time right analysis. This is due to the enormous pressure of cost, mass, time to market and availability of prototype vehicles for testing. Use of finite element methods enables to upfront predict the system behavior in operating conditions and evaluation of structural strength. In vehicle product development process, hood slam durability evaluation is one of the important tests for body closure structure. Current work showcases an effort made for developing virtual hood slam test. The virtual model consists of BIW, hood, hinge joint, interface like CRFM (cooling-radiator-fan module) and latch mechanism with spring preload. Analysis performed with LSDyna solver. An impact loading is applied by converting potential energy to kinetic energy, mimicking the hood dropping from a specified height on the hood latch.
2016-04-05
Technical Paper
2016-01-1380
S. Khodaygan, Amir Ghasemali, Hamed Afrasiab
Abstract One of the most important characteristics of industrial products, especially mechanical set-ups, is considering the tolerances of production and assembly of these set-ups, which directly influences the products’ operations. In sheet metal structures, due to the high flexibility of the sheets, the errors appeared while assembly will be as highly influential as the errors due to the production tolerance of the sheets. As a result, having a comprehensive model which could analyze the assembly process of these structures and also clarifies the relation between the tolerance of the parts and the ultimate changes of the set-up will be of considerable importance. During the assembly process, the contact effect between the components is inevitable. If such effect is not considered, the contact surfaces will permeate. The purpose of this paper is to present a method to analyze the tolerance of flexible sheet structures, considering the contact effect between surfaces.
2016-04-05
Technical Paper
2016-01-1384
Mengshi Deng, Jian Lan
Abstract 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.
2016-04-05
Technical Paper
2016-01-0022
Kenta Morishima, Shigeru Thomas Oho, Satoshi Shimada
Abstract A virtual power window control system was built in order to look into and demonstrate applications of microcontroller models. A virtual ECU simulated microcontroller hardware operations. The microcontroller program, which was written in binary digital codes, was executed step-by-step as the virtual ECU simulation went on. Thus, production-ready codes of ECUs are of primary interest in this research. The mechanical system of the power window, the DC motor to lift the window glass, the H-bridge MOSFET drivers, and the current sensing circuit to detect window locking are also modeled. This means that the hardware system of the control system was precisely modeled in terms of mechanical and circuit components. By integrating these models into continuous and discrete co-simulation, the power window control system was analyzed in detail from the microscopic command execution of the microcontroller to the macroscopic motion of the window mechanism altogether.
2016-04-05
Technical Paper
2016-01-0256
Hideaki Nagano, Kenji Tomita, Yasuhiro Tanoue, Yuji Kobayashi, Itsuhei Kohri, Shinsuke Kato
Abstract In the winter, windshield glass fogging must be prevented through the intake of outdoor air into a vehicle. However, the corresponding energy loss via the ventilation system cannot be ignored. In the present study, the defogging pattern on the windshield is evaluated and the water vapor transportation in the flow field in the vehicle is analyzed in order to investigate the ventilation load by means of a numerical simulation. Some examined cases involve new outlet positions. Additionally, a new, energy-saving air supply method for defogging, with so-called “double-layer ventilator”, is proposed. In this method, one air jet layer is obtained via a conventional defogging opening in the vicinity of the windshield, supplying an outdoor air intake. The other jet consists of recirculated air that covers the outdoor air, preventing it from mixing with the surrounding air.
2016-04-05
Technical Paper
2016-01-0246
Rupesh Sonu Kakade, Prashant Mer
Abstract Vehicle occupants, unlike building occupants, are exposed to continuously varying, non-uniform solar heat load. Automotive manufacturers use photovoltaic cells based solar sensor to measure intensity and direction of the direct-beam solar radiation. Use of the time of the day and the position - latitude and longitude - of a vehicle is also common to calculate direction of the direct-beam solar radiation. Two angles - azimuth and elevation - are used to completely define the direction of solar radiation with respect to the vehicle coordinate system. Although the use of solar sensor is common in today’s vehicles, the solar heat load on the occupants, because of their exposure to the direct-beam solar radiation remains the area of in-car subjective evaluation and tuning. Since the solar rays travel in parallel paths, application of the ray tracing method to determine solar insolation of the vehicle occupants is possible.
2016-04-05
Technical Paper
2016-01-0240
Ruobing Zhan, Gangfeng Tan, Bo Yang, Zhiwei Zhang, Tie Wang, Cenyi Liu, Xintong Wu, Yanjun Ren, Haobo Xu
Abstract The Organic Rankine Cycle System (ORC) is an effective means to use the solar energy. The system adopts the solar energy on the car roof as the heat source to make the ORC work and drive the thermoelectric air-conditioner. It can improve the entering comfort on the parking condition and the vehicle energy utilization efficiency. In this research, the system comprehensively applied the principle of sunshine concentration, heat collection and photo electricity. Then considering the working condition and performance features of ORC system, the car roof was designed to have a compact structure, through which the efficiency of the solar vehicle system could be improved. Firstly, the research analyzed the heat source temperature and the heat flux impact on the output power of the ORC system. After that, the performance of heat collection was identified according to the given thermoelectric air-condition’s power requirements.
2016-04-05
Technical Paper
2016-01-0216
Ramanand Singh, Remesh Kuzhikkali, Nitesh Shet, Sekarapandian Natarajan, Govind Kizhedath, Murugan Arumugam
Fogging (i.e. condensation of water vapor) in headlamps in severe weather conditions present both a performance and potential safety concern for automotive companies. Conventional headlamps are based on incandescent bulbs. In recent times, LED lighting has increasingly become the norm. However, LED based headlamps are prone to higher levels of fogging because they inherently produce less heat than the conventional incandescent or halogen bulbs. A headlamp design must be able to dispose all the formed condensate/fog in a fixed time even under severe thermal conditions. It is of great importance for the car manufacturer to be able to simulate the risk of condensation early in the design stage with an eye on the overall cost reduction. The combined use of experimental studies and numerical modelling is important to optimize headlamp design and to produce high-performance headlamps.
2016-04-05
Technical Paper
2016-01-0217
Somnath Sen, Mayur Selokar, Diwakar Nisad, Kamal Kishore
Abstract Adequate visibility through the vehicle windshield over the entire driving period is of paramount practical significance. Thin water film (fog) that forms on the windshield mainly during the winter season would reduce and disturb the driver’s visibility. This water film originates from condensing water vapor on inside surface of the windshield due to low outside temperatures. Primary source of this vapor is the passenger’s breath, which condenses on the windshield. Hot and dry air which impinges at certain velocity and angle relative to the windshield helps to remove the thin water film (defogging) and hence improves driver’s visibility. Hence a well-designed demisting device will help to eliminate this fog layer within very short span of time and brings an accepted level of visibility. An attempt is made here to design and develop a demisting device for a commercial vehicle with the help of numerical and analytical approach and later on validated with experimental results.
2016-04-05
Technical Paper
2016-01-0208
Xuzhi Du, Zhigang Yang, Hua Zhou, Qiliang Li, Zheyan Jin
Abstract The effect of jet geometry on flow, heat transfer and defrosting characteristics was numerically investigated for elliptic and rectangular impinging jets on an automobile windshield. Initially, various turbulence models within the commercial computational fluid dynamics (CFD) package FLUENT were employed and validated for a single jet, and the results indicated that the impinging jet heat transfer was more accurately predicted by the SST k -ω turbulence model, which was then utilized for this study. The aspect ratios (AR) of elliptic and rectangular jets were respectively 0.5, 1.0, and 2.0, with jet-to-target spacing h/d=2, 4 and jet-to-jet spacing c/d=4, and all those situations were numerically analyzed with the same air mass flow and jet open area. It was observed that the heat transfer coefficient and defrosting performance of the inclined windshield were significantly affected by the shape of the jet, and the best results were obtained with the elliptic jet arrangements.
Viewing 211 to 240 of 4707