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2018-04-13
Journal Article
2018-01-9176
Krystian J. Link, Nicholas Pohlman
Windshield deicing performance is a key metric for HVAC system development and optimization within the sphere of commercial vehicle design. The primary physical properties that drive this metric are pressure drops in the HVAC ducting, flow rate of the air through the system, and the transient warm up curve of the HVAC unit. However, many design engineers also have to take underhood packaging into consideration while trying to optimize a new HVAC system design. This study leverages historical deicing simulation methodologies in conjunction with modern computational horsepower so as to optimize the HVAC ductwork in the studied commercial truck at the front end of the design process. By iterating on a design in the computational domain under steady-state and transient flow and thermal conditions, a robust HVAC system design can be created even prior to the prototyping stage of development.
2018-04-13
Journal Article
2018-01-9178
Helena Martini, Peter Gullberg, Lennart Lofdahl
This paper deals with the analysis of cooling airflow for two different front-end designs of a heavy truck. The first design is a cab-over-engine (COE) cab; the second is a Soft Nose (SN) cab, which in this case is basically an elongation of the grille area of the COE cab to obtain a smoother shape of the cab. The SN model used in this investigation was extended 200mm from the COE front. Computational Fluid Dynamics (CFD) was used as the tool for examining the aerodynamic properties of the vehicle models. The configurations were evaluated both with inactive and active heat exchangers, in order to examine the effect of heating the air on the drag co-efficient and also to determine the cooling capacity of the different models. A sub- study was performed where different opening percentages of the grille area was investigated to determine the minimum percentage opening that would be needed to achieve a radiator Top Tank Temperature (TTT) value below a target limit of 100°C.
2018-04-13
Journal Article
2018-01-9175
Surya Narayana Prasa Vegendla, Tanju Sofu, Rohit Saha, Long-Kung Hwang, Mahesh Madurai Kumar
A 3D CFD underhood thermal simulations are performed in two different vehicle platooning configurations; (i) single-lane and (ii) two-lane traffic conditions. The vehicle platooning consists of two identical vehicles, i.e. leading and trailing vehicle. In this work, heat exchangers are modeled by two different heat rejection rate models. In the first model, a constant heat rejection rates are considered as similar to no-traffic vehicle condition. In the other model, a varied heat rejection rates are implemented by considering an aerodynamic influence on fuel consumption rates. In a constant heat rejection rate model, the trailing vehicle thermal performance is significantly dropped in single-lane traffic due to reduced oncoming cold mass air flow velocities from leading vehicle. Also, the similar observations are found in two-lane traffic but at higher vehicle separation distances.
2018-04-13
Journal Article
2018-01-9075
Bin Yan
Abstract: ICE ON/OFF control strategy is critical for fuel economy in the hybrid electric vehicle (HEV). The fuel cumsumption cut off at ICE is at OFF state when the vehicle stops especially at vehicle jams. It significantly profits for more fuel saving. Motor-only drive mode is rarely used in real-time control because of the power system meet the uncertain driver demand. Battery state of charge (SOC) balance also affects ICE ON/OFF control decision. ICE ON/OFF state optimization is still a critical problem that is rarely effectively resolved. Minimum Principle was used in real-time control and has a global optimization in many papers. However, there is no paper to apply this algorithm in ICE ON/OFF control optimization. This paper introduces a novel control method using Minimum Principle to select an appropriate ICE state, which extracts rules from the optimal results applied to real-time control based on predicted route information.
2018-04-13
Journal Article
2018-01-9076
Anne Marie Lewis, Gregory Keoleian, Jarod Kelly
Vehicle lightweighting and advanced powertrains, including hybrid electric systems and high efficiency engines, have the potential to increase fuel economy and decrease life cycle energy and greenhouse gas (GHG) emissions. However, the energy and GHG impact over the entire vehicle life cycle is dependent on the energy and emissions required to produce lightweight materials and fuels. Recent work has used life cycle assessment (LCA) to evaluate diverse vehicles and fuels using a novel design harmonization technique. The current work describes this approach in further detail and provides an example of its application for a moderate lightweighting scenario for an internal combustion vehicle (ICV), hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle (PHEV). This type of apples-to-apples comparison is enabled by functional equivalency metrics, which are defined as part of the design harmonization technique and held constant across all vehicles.
2018-04-03
Technical Paper
2018-01-1184
Toru OHGAKI, Masanori Matsuda, Mitsunori Matsumoto
Compared to conventional hybrid electric vehicles, plug-in hybrid vehicles have a larger-capacity battery and an onboard charger. These devices are mounted in functionally optimal locations, so it is a challenge to provide a thermal management system that achieves a good balance between high cooling performance and low cost. The battery should be operated at required temperature to secure safety and durability at high temperatures, and to suppress drops in output and capacity. However, setting separate cooling systems suited for each device leads to both an increased cost and weight. Therefore, an integrated water cooling system was devised for the battery, charger, and DC-DC converter, and the cooling performance was verified through simulations and tests. A valve installed before the battery in the cooling circuit allows it to be bypassed when coolant temperature rises due the charger or low–speed engine operation, helping to preserve battery life.
2018-04-03
Technical Paper
2018-01-1183
Tharunnarayanan Arthanari, Sathish Kumar S
In today’s automobile industries to improve the fuel economy lots of weight reduced in all the systems of the vehicle, particularly in the engine cooling system. Due to the lighter weight engine cooling systems, the vehicles might face many temperature challenges and sustainability issues. The automotive cooling system has unrealized potential to improve internal combustion engine performance through enhanced coolant temperature control and reduced parasitic losses. The idea of this work is to come up with an optimal engine cooling module design by downsizing the heat exchangers and reducing the coolant flow volumes without compromising the functional requirements. For this study a plug-in hybrid electric vehicle (PHEV) engine internal cooling system is modelled in GT-Suite. The PHEV cooling network comprises of high temperature (HT) loop, low temperature loop (LT) loop and the battery loop.
2018-04-03
Technical Paper
2018-01-1182
Bowen Wen, Sukru Yaren Gelbal, Bilin Aksun Guvenc, Levent Guvenc
SAE Level 4 and Level 5 autonomous vehicles require novel applications of localization, perception, control and artificial intelligence technology in order to offer innovative and disruptive solutions to current mobility problems. This paper concentrates on low speed autonomous shuttles that are transitioning from being tested in limited traffic, dedicated routes to being deployed as SAE Level 4 automated driving vehicles in urban environments like college campuses and outdoor shopping centers within smart cities. The Ohio State University has designated a small segment in an underserved area of campus as an initial autonomous vehicle (AV) pilot test route for the deployment of low speed autonomous shuttles. This paper is on developing solutions to the localization and perception challenges of this planned pilot deployment.
2018-04-03
Technical Paper
2018-01-1113
Chen Huang, Chen wang, Keqiang Li, Long Chen, Yugong Luo, Xiaoqiang Sun
In order to understand the complex nonlinear relationship between the influencing factors and the forces, the vertical sliding (braking and driving), side bias and complicated working conditions were carried out on the KHAT low-speed flat tire test-bed respectively. Furthermore, under the complicated working conditions, the influence of the factors such as tire pressure, vetical load, tire speed, sideslip angle and side rake angle on the lateral force as well as the longitudinal force are analyzed qualitatively. In the light of complex nonlinear relationship, a BP neural network tire mechanics model is established. The model is trained by experimental datas and compared with the "Magic Formula" tire model. The results show that the established BP neural network model can better approximate the test curve, and verify the validity of the model. It provides a reference for the study of tire mechanical properties.
2018-04-03
Technical Paper
2018-01-1114
Sathish Kumar Prasad, Dayalan P, Ramya Balasubramanian
Durability analysis is essential for vehicle validation and is carried out with the inputs of different road conditions. The selection of roads for durability analysis is critical and should represent the actual working conditions for the selected vehicle. Generally, the road conditions are subject to change with respect to time. To overcome the above, road profile data is an essential parameter which helps to represents and categorize roads in terms of ISO road class. The ISO road classes objectively classify the roads with respect to roughness. This classification holds good by categorizing the signals to the respective road classes rather than different test roads. The road profiles are measured using inertial profiler methodology along with vehicle acceleration and displacement responses, also analyzed and categorized with respect to ISO road class.
2018-04-03
Technical Paper
2018-01-1115
Xiaoxue Liu, Liangyao Yu, Sheng Zheng, Jinghu Chang
As the development of intelligent vehicle and intelligent tire, more and more sensors are embedded in tire for critical information collection and transmission, including longitudinal force, vertical force, road adhesive coefficient, tire temperature, tire pressure, etc. Tire parameters are essential for vehicle dynamic control. Due to the close and poor environment inside the tire, it’s hard to change the embedded cell battery. The power limitation of the battery can reduce the real-time data transmission frequency and the safety. A possible solution is to design in-tire energy harvester to convert potential energy to electricity, thus charge the sensors. Based on electromagnetic induction or piezoelectric effect, this paper designs a novel device of in-tire energy harvester, making use of the tire deformation when the tire contacts the road and the caused vibration within the tire.
2018-04-03
Technical Paper
2018-01-1116
Vikas Birajdar, Javad Baqersad, Jennifer Bastiaan, Mohammad Behroozi
With the recent advances in rapid modeling and rapid prototyping, accurate simulation models for tires are very desirable. Selection of a tire slip model depends on the required frequency range and nonlinearity associated with dynamics of vehicle. This paper presents a brief overview of three major slip concepts including ‘Stationary slip’, ‘Physical transient slip’ and ‘Pragmatic transient slip’; tire models use these slip concepts to incorporate tire slip behavior. The review illustrates that there can be no single accurate slip model which could be ideally used for all modes of vehicle dynamics simulations. Currently, a semi-analytical tire model (KU-Tire) for intermediate frequency (up to 100Hz) is under development at Kettering University.
2018-04-03
Technical Paper
2018-01-1117
Jennifer M. Bastiaan
A smart tire prototype is fabricated and physically tested on a ground vehicle. The smart tire prototype includes two in-tire piezoelectric deformation sensors and a rotary encoder. The piezoelectric sensors are located at the tire sidewall and are used to measure sidewall strain; one is oriented longitudinally and the other is oriented radially. The rotary encoder directly measures wheel angular position, along with an angular position index. Data from the piezoelectric sensors and the rotary encoder are processed using a radial basis function neural network. The neural network is employed to estimate the three orthogonal tire forces and the tire aligning moment as developed at the wheel center. The data processing methodology for the in-tire strain and angular position measurements is formulated first using virtual sensor measurements as computed by a tire finite element model.
2018-04-03
Technical Paper
2018-01-1106
Jian Zhu, Huairui Guo
Management always wants to know how many claims a product will have by the end of its warranty. Therefore, one of the common tasks for a reliability or durability engineer is to predict warranty returns. Traditionally, Weibull analysis is used on early warranty data to obtain a Weibull model, and then this Weibull model is used for prediction. In a Weibull model, probability of failure is a function of customer usage. In automobile industry, customer usage is measured either in month in service (MIS) or in mileage. For a given MIS or a mileage, the probability of failure of a product is calculated using the obtained Weibull model and the number of claims can be predicted, given the sales volume is known. However, the above traditional Weibull analysis has some drawbacks. It only uses “customer usage (time)” as a factor to make prediction. Other factors that also contribute to failures are ignored. If a failure is caused by “time” only, then the Weibull prediction works.
2018-04-03
Technical Paper
2018-01-1108
Junkui (Allen) Huang, Shervin Shoai Naini, Richard miller, John R. Wagner, Denise Rizzo, Katherine Sebeck, Scott Shurin
Hybrid electric vehicles offer the advantages of reduced emissions and greater travel range in comparison to conventional and electric ground vehicles. Regardless of propulsion strategy, efficient cooling of electric motors remains an open challenge due to the operating cycles and ambient conditions. The on-board thermal management system must remove the generated heat so that the motors and other vehicle components operate within their designed temperature ranges. In this paper, an integrated thermal structure, or “cradle”, efficiently transfers heat within the motor shell to the end plates for transmission to an external thermal bus will be presented. A radial array of heat pipes function as an efficient thermal connector between the motor and heat connector or thermal bus depending on the configuration. Cooling performance has been evaluated for various driving cycles.
2018-04-03
Technical Paper
2018-01-1110
Dan Negrut, Hammad Mazhar, Radu Serban, Milad Rakhsha
We present an approach in which we use simulation to capture the two-way coupling between the dynamics of a military vehicle and that of a fluid that sloshes in a tank attached to the vehicle. The simulation is carried out in Chrono and builds on support provided by two modules: Chrono::FSI (Fluid-Solid Interaction) and Chrono::Vehicle. The dynamics of the fluid phase is governed by the mass and momentum (Navier-Stokes) equations, which are discretized in space via a Lagrangian approach called Smoothed Particle Hydrodynamics. The vehicle dynamics is the solution of a set of differential algebraic equations of motion. All equations are discretized in time via a half-implicit symplectic Euler method. This solution approach is general -- it allows for fully three dimensional (3D) motion and nonlinear transients. We demonstrate the solution in conjunction with the simulation of a vehicle model that performs a constant radius turn and double lane change maneuver.
2018-04-03
Technical Paper
2018-01-1111
Shervin Shoai Naini, Junkui (Allen) Huang, Richard miller, John R. Wagner, Denise Rizzo, Katherine Sebeck, Scott Shurin
Improved propulsion system cooling remains an important challenge in the transportation industry as heat generating components, embedded in ground vehicles, trend toward higher heat fluxes and power requirements. The further minimization of the thermal management system power consumption necessitates the integration of parallel heat rejection strategies to maintain prescribed temperature limits. When properly designed, the cooling solution will offer lower noise, weight, and total volume while improving system durability, reliability, and power use. This study investigates the integration of high thermal conductive materials, carbon fibers, and heat pipes with conventional liquid cooling to create a hybrid thermal bus to move the thermal energy from the heat source(s) towards the ambient surroundings. The innovative design can transfer heat between the separated heat source(s) and heat sink(s) without sensitivity to gravity.
2018-04-03
Technical Paper
2018-01-1129
Yuhang Tang, Wei Deng, Bin Liu, Tie Gang Hu, Xiangang Wang, Qing Yang, Bo Jiang, Ling Lin, Zhang Song ZHAN, Long Min
ChangAn has upgraded its 1.6L naturally aspirated GDI engine to meet future fuel economy and emission regulation base on its previous 1.6L naturally aspirated GDI engine, the major upgrade include a high 13 Compression ratio(CR),35Mpa direct injection system ,cooled EGR, Thermal management module ,and extensive measures to reduce friction. with this new engine, the vehicle fuel consumption is reduced by 9%, and meet the China6b emission regulation without GPF.
2018-04-03
Technical Paper
2018-01-1128
Kenan Muric, Per Tunestal, Arne Andersson, Lennart Andersson, Kerstin Oom
Selective Non-Catalytic Reduction (SNCR) used to reduce the emissions of nitrogen oxides has been a well-established technology in the power plant industry for a couple of decades. In the compression ignition engine application, the technology has not been applicable due to low exhaust temperatures, which makes the SCR (Selective Catalytic Reduction) system essential for efficient nitrogen oxide (NOx) reduction in order to fulfill the environment legislation. For the Double Compression Expansion Engine (DCEE) the complete expansion cycle is split in two separate cycles, i.e. the engine is a split cycle engine. In the first cylinder the combustion occurs and in the second stage the combustion gas is introduced and further expanded in a low pressure expansion cylinder. The combustion cylinder is connected with the expansion cylinder through a large insulated high pressure tank.
2018-04-03
Technical Paper
2018-01-1131
Tianze Shi, Kangda Chen, Han Hao, Zongwei Liu, Fuquan Zhao
Hybrid electric vehicle (HEV) is regarded as an important technology in solving the energy and environment crisis. In this paper, the HEV technology applied in passenger cars by major automotive OEMs such as Toyota, Honda, GM, Ford, VW, BMW are investigated. The configuration diagrams for each OEM are presented. Based on the architecture analysis, a classification is done according to similar structures and performances. Further, a cost estimation method for HEV is presented based on the preliminary tear-down research done by Environment Protection Agency (EPA). Meanwhile, the logarithmic relation between fuel consumption (FC) improvement and degree of hybridization (DOH) is discovered by investigating 30 different hybrid cars. Combining the cost estimation and relation between FC/DOH, the hybridization cost for cars to meet the FC regulations (FCR) can be calculated.
2018-04-03
Technical Paper
2018-01-1130
Xinyu Ge, Xinyu Li, Ying Wang
Many automakers rolled out new vehicles models which can achieve partial autonomous driving (SAE level 2 automation) or conditional autonomous driving (SAE level 3 automation) in recent years. SAE level 4 autonomous driving vehicles are expected on roads in near future according to automakers development plans. All levels of governing authorities also published related regulations to provide guidelines for the road tests of autonomous vehicles, and these regulations and their amendments will also impact the future application and adoption of autonomous vehicles. According to SAE J3016 standard, SAE level 4 autonomous vehicles do not require end user to take over control when automation control system cannot perform predetermined functions. Any user in a SAE level 4 autonomous vehicle can be regarded as passenger from technical perspective. However whether an autonomous vehicle has an ethical responsibility is still in a discussion.
2018-04-03
Technical Paper
2018-01-1133
Xiao Yu, Zhenyi Yang, Shui Yu, Xuemin huo, David Ting, Ming Zheng, Liguang Li
In this research, a boosted current spark strategy was proposed to improve the combustion stability and controllability of lean burn spark ignition engines. Firstly the boosted current spark system was tested under pressurized and different flow conditions. Results showed that the boosted current maintained the discharge duration and current level in the flow and pressurized conditions, especially when the current level was high. Then methane air mixture was ignited in a combustion chamber to study the effect of the boosted current on flame propagation. The results showed that the boosted current had negligible effect on flame propagation under quiescent conditions. However, significant improvement was observed with the boosted current spark ignition when the combustible mixture was under flow conditions. Lastly the boosted current strategy was used in a spark ignition engine operating under lean conditions.
2018-04-03
Technical Paper
2018-01-1132
Alessandro Cimarello, Valentino Cruccolini, Gabriele Discepoli, Michele Battistoni, Francesco Mariani, Carlo Grimaldi, Massimo Dal Re
It has been proved that Radio Frequency Corona, among other innovative ignition systems, is able to stabilize combustion and to extend the engine operating range in lean conditions, with respect to conventional spark igniters. This paper reports on a sensitivity analysis on the combustion behavior for different values of Corona electric control parameters (supply voltage and discharge duration). Combustion analysis has been carried out on a single cylinder PFI gasoline-fueled optical engine, basing on both indicating measurements and imaging. A high-speed camera has been used to record the natural luminosity of premixed flames and the obtained images have been synchronized with corresponding indicating acquisition data. Imaging tools allowed to observe and measure the early flame development, providing information which are not obtainable by a pressure-based indicating system.
2018-04-03
Technical Paper
2018-01-1135
Prasanna Chinnathambi, Bryce Thelen, Michael naylor, Dave Cook, Elisa Toulson
An auxiliary fueled pre-chamber ignition system can be used in an IC engine to provide lean limit extension with minimal cyclic variability and low emissions. Geometry and distribution of the pre-chamber nozzles forms an important criteria for performance of these systems since they are responsible for transferring and distributing the ignition energy into the main chamber charge. Combustion performance of pre-chamber nozzle tips with a single jet, dual diverging jets and dual converging jets for a methane fueled pre-chamber ignition system is studied in a rapid compression machine. Upon entering the main chamber, the dual diverging jets penetrates the main chamber in opposite directions creating two jet tips, while the dual converging jets, converge into a single location within the main chamber. Both these configurations minimizes jet-wall impingement compared to the single jet.
2018-04-03
Technical Paper
2018-01-1134
Shouvik Dev, Navjot Singh Sandhu, Mark Ives, Shui Yu, Ming Zheng, Jimi Tjong
Close-loop feedback combustion control is essential for improving the internal combustion engines to meet the rigorous fuel efficiency demands and emission legislations. A vital part is the combustion sensing technology that diagnoses in-cylinder combustion information promptly, such as using cylinder pressure sensor and ion current measurement. The promptness and fidelity of the diagnostic are particularly important to the potential success of using intra-cycle control for abnormal cycles such as super knocking and misfiring. Enormous researches have demonstrated the use of ion-current sensing as feedback signal to control the spark ignition gasoline engines, with the spark gap shared for both ignition and ion-current detection. The conventional technique cannot extract the combustion ion-current from the measured signal during the sparking process, since the sparking current overwhelms the combustion ion current.
2018-04-03
Technical Paper
2018-01-1121
Yuhang Gao, Yunkai Gao, Rui Qian, Yanan Xu, Chi Wu
Carbon fiber reinforced plastic (CFRP) composites have gained particular interests due to their high specific modulus, high strength, resistance to environment, lightweight. In the automotive industry, numerous studies have been ongoing to replace the metal component with CFRP for the purpose of weight saving. One of the significant benefits of CFRP laminates is the ability of tailoring fiber orientation and ply thickness to meet the acceptable level of structural performance with little waste of material capability. This study focused on the concurrent optimization of ply orientation and thickness for CFRP laminated engine hood, which was based on the gradient-based discrete material and thickness optimization (DMTO) method. Two manufactural constraints, namely contiguity and intermediate void constraints, were taken into account in the optimization problem to reduce the potential risk of cracking matrix of CFRP.
2018-04-03
Technical Paper
2018-01-1123
Max Sardou
SARDOU SAS has developed highly stressed composites parts for 36 years. SARDOU SAS and QUALITY INDUSTRIAL PRODUCT jointly invented and patented composite “C” springs in 1993. We have designed and tested ultra-performance “C” springs, giving an incredible energy density of 1350 joules per kilogram (compared to 300 for steel springs). This energy density means a potential 78% weight savings! But in the last century, weight savings was not a must and platform personnel were reluctant to use anything else than coil springs. So in 2002, in order to comply with the wishes of platform personnel, we have invented and developed composite coils springs. Composite coils springs are the best choice for McPherson suspensions. We have identified that the weak point, in composite coils springs, is its epoxy matrix. During heavy loading, the matrix undergoes micro cracking. Then, during repeated loadings, micro cracks propagate and merge, transforming the matrix into a fine powder.
2018-04-03
Technical Paper
2018-01-1120
Bin Li, Xiaobo Yang, James Yang
In this paper, based on our previously proposed preliminary out-of-plane tire model, a complete out-of-plane flexible ring tire model is further developed by considering the variation of dimension and parameter value among different slices of the tire model. This tire model is validated via various MSC/ADAMS FTire® virtual cleat tests. Especially, the cleat tests with non-zero tire camber angles and non-symmetric cleat shapes, which can better capture the out-of-plane tire properties, are included. By comparing the predicted results of the proposed tire model with FTire® for various cleat tests, it shows that the complete out-of-plane flexible ring tire model is better at fully representing the actual tire properties for some complicated cleat testing scenarios.
2018-04-03
Technical Paper
2018-01-1122
Haseeb Ali, Ahmad Waqar Tehami
Composites are wonderful materials that have revolutionized the field of engineering because they can provide more versatility when compared to other materials and can be tailored to have maximum strength and stiffness. Experimental investigation was carried out to study the influence of fiber volume fraction, fiber length and percentage of fillers on fracture toughness ,fracture energy and impact energy of glass fiber reinforced composite. Panels with different configurations were made using fiber glass chopped strand mat and unidirectional roving with epoxy resin. Wet Hand Layup method was adopted for fabrication of panels with different fiber volume fractions and filler density while Mold Pouring Technique was used for making panels with different fiber lengths. ASTM D-5045 was consulted for the development of test specimens to conduct flexural testing of these panels.
2018-04-03
Technical Paper
2018-01-1127
Alejandro Aljure, Xavier Tauzia, Alain Maiboom
Diesel engines are being more commonly used for light automotive applications, due to their higher efficiency. However, pollutant emissions can be higher than their gasoline counterparts, being difficult to reduce and control because reducing one pollutant increases another. One way to reduce emissions is by using multiple injection strategies. However, understanding multiple injections is no easy task, so far done by trial and error and experience. Therefore, a numerical 1D model is to be adapted to simulate multiple injection situations in a diesel engine. In a previous paper by the authors, an existing model was adapted with a thermal dilatation model to consider both radial and axial dilatations in the diesel spray. The base model used is that of Ma et al (based on the Eulerian model of Musculus and Kattke for inert diesel jets).
Viewing 1 to 30 of 112266