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Fan and fan-shroud design is critical for underhood air flow management. The objective of this work is to demonstrate a method to optimize fan-shroud shape in order to maximize cooling air mass flow rates through the heat exchangers using the Adjoint Solver in STAR-CCM+®. Such techniques using Computational Fluid Dynamics (CFD) analysis enable the automotive/transport industry to reduce the number of costly experiments that they perform. This work presents the use of CFD as a simulation tool to investigate and assess the various factors that can affect the vehicle thermal performance. In heavy-duty trucks, the cooling package includes heat exchangers, fan-shroud, and fan. In this work, the STAR-CCM+® solver was selected and a java macro built to run the primal flow and the Adjoint solutions sequentially in an automated fashion.

In order to optimise the dynamic properties of commercial vehicles, a programme system of particular flexibility has been developed. For model formation, the system is largely similar to FE programmes. The vehicle model is built up of individual modules based on the input data. In the case of components for which the data is difficult to ascertain by computer, experimental performance maps can be used. In terms of kinematics and physics, the programme is non-linear. Following an explanation of the theoretical basis, three examples of simulation from the fields of handling and vehicle dynamics are shown and compared with test results.

Loads applied to soil by agricultural machines can increase soil bulk density and reduce crop, production. Over 80% of a field may be trafficked at least once each year when producing corn or soybeans. When most field operations are performed, soil has a moisture content near field capacity and, therefore, is in a compactable condition. Changes in bulk density, cone index, and surface elevation caused by traffic were found to depend upon the tillage system used. Combine wheels depressed the soil surface from 1 to 4 cm. Reductions in growth rate and yield of corn indicate that tillage for seedbed preparation does not remove the effect of wheel tracks made during that tillage. Lighter machines, lower ground pressures, appropriate tillage, and controlled traffic can minimize soil compaction effects on crop production.

Modern agriculture has evolved dramatically over the past half century. To be profitable, farms need to significantly increase their crop yields, and thus there are amplified demands on farming equipment. Equipment duty cycles have been raised in scope and duration, as the required output of the agricultural industry to sustain a growing population has stimulated the need for further advances in effective productivity gains on the farm. The mainstay mechanical assistant to the farmer, the tractor, has also evolved with the changes in modern agriculture to meet the requirements of these newer tasks. Larger, more capable vehicles have been introduced to help farmers efficiently meet these demands. At the same time, the current generation of tractor diesel engine lubricants has facilitated high levels of performance in the agricultural equipment market for many years. This is a testament to the role modern lubricants play in productivity in such a critical industry.

Farmers are a small group, mostly college educated who run multi-million dollar yearly operations. Recent favorable economics has allowed this sector to look at new technology and determine the best way to invest in it. New considerations in the last few years have led to minimum/alternative tillage and planting, site specific farming decisions and small technology groups of farmers. The authors have put together their thoughts and wants which should be evaluated by future suppliers of technology and farm machinery.

A new substantially common tractor cab has been developed to suit a wide range of tractor sizes, powers, and configurations, and to be suitable for use in all areas of the world. The design incorporates advanced truck cab technology to provide for high volume production in an attractively styled package. Computer programs were extensively used to meet structural and mounting objectives of the design.

The paper presents a low-cost method of very fast diagnosis of general technical state of a bus fleet. The engine power is estimated from the no-load acceleration time. A low-cost PC and a very simple interface allow obtaining in a few minutes pertinent information if the vehicle can run or not. If not, more sophisticated tests are necessary.

Studies have been published which address fast filling of Natural Gas Vehicle (NGV) fuel containers. Diggins states that NGV fuel containers cannot be fully filled during a fast fill, and that all-composite fuel containers cannot be filled as full as other types of fuel containers. There are issues in this prior work which may have a significant effect on the author’s conclusions. Fast fill testing conducted by Powertech Labs shows the Lincoln Composites’ fuel container has significantly better fill performance than projected by Diggins. Testing of a dispenser control system by Kountz and Blazek demonstrates all types of fuel containers can be properly filled with proper dispenser control algorithms and performance.

ANSYS Mosaic™ meshing technology automatically conformally connects different types of meshing elements with general polyhedron elements. Poly-Hexcore, the first application of the Mosaic technology, fills the volume region with octree hexahedra, boundary layer with the high-quality layered poly-prism and conformally connect these two meshes with general polyhedron elements. A generic vehicle model - the DrivAer car, developed at the Technical University of Munich (TUM) in cooperation with the Audi AG and the BMW group, is used to validate the Mosaic meshing technology to predict complex aerodynamic phenomenon around the car. The Mosaic meshing technology is parallel scalable on high-performance computing (HPC) platform. For example, on ANSYS HPC (CPU: 2x Intel(R) Xeon(R) Gold 6142 CPU @ 2.60 GHz, RAM: 192 GB (6 GB/core)), approximately 63 million element mesh is 6.5 times faster, when scaled from serial compute core to 32 parallel compute cores.

The design requirements for fastening FRP (Fiberglass Reinforced Plastic/Plywood) panels in shipping containers, truck bodies, and truck trailers are discussed in this paper. A summary of test values for designing connections to structural components, attaching load restraining devices, and results of testing two typical assemblies is included.

Nowadays, a lightweight component design plays a significant role in both cost of a vehicle and fuel economy in competitive heavy duty truck industry. This paper describes the optimization study of an Anti-Roll Bar (ARB) bracket used in a heavy duty truck. ARB system is used to avoid rolling of a vehicle. In order to measure real forces acting on ARB links, calibration study is performed in laboratory conditions. According to this study, measured strains are correlated with theoretical strain-force curve. After the correlation study, fatigue based topology optimization is made on ARB cast iron bracket according to correlated Road Load Data (RLD) which is performed at Proving Ground. Most of the optimization studies in the literature depend on maximum static loading condition. However, many components or structures in the industry subjected to fluctuating loads when they are in service condition.

Due to the growing necessity to reduce time for new products development, or even to evaluate the reliability of them, a rationalization tendency of the tests has been observed in the field through more and more representative bench tests in a shorter time and with smaller costs. In the automotive industry, the amount of simulated parameters is always increasing; therefore it is necessary to collect a great number of sign measurements in suspension systems (accelerations, temperatures, strokes and deformations), using prototype vehicles. In the present paper we will present the measurements made in a representative track, where it was possible to analyze the measured signs. In a second step they were compiled and compacted, and finally applied in a one-axial bench test. This procedure permits to get a correlation between field and laboratory results.

The boundary load of the light truck cab fatigue analysis is the force of the cab mounting system, which cannot be directly measured. In the absence of a physical prototype, the fatigue load of the cab cannot be extracted through virtual iteration. Aiming at the problem of fatigue analysis in the early stage of the car-free cab, the virtual proving ground technology is used to extract fatigue load and do fatigue analysis in this paper. Using the virtual road as the excitation, the simulation analysis of the whole vehicle virtual proving ground is carried out, and the wheel center load and the cab mounting force are obtained. Comparing the simulation load with the signal required on the proving ground, it is found that the extracted virtual load is consistent with the actual vehicle load in the time domain and frequency domain. The retention of pseudo-damage of the six-component load of the wheel center can meet the precision control requirements of the vehicle load decomposition.

A proposal is presented for data condensation of long term signals. The purpose of the condensation is to obtain a short one or two minute dynamic force signal. The short signal can be applied to a finite element model (FEM) in order to compute the dynamic stress trace at any point in the structure. The fatigue damage produced by the short signal creates essentially the same damage per hour as the long signal. The structural component simulated in the study is a lattice dragline boom. Forces acting at the boom point transform into stresses throughout the lattice.

Fatigue tests were performed on five kinds of fillet welded joints on 2.6 mm thick HSLA steel sheets, to evaluate the fatigue life of automotive HSLA chassy frame with different joint geometries under various loading conditions. Specimens were made by CO2 gas arc welding with 1.2 mm diameter wire. During the fatigue tests at stress ratio (R)=−1, dynamic strain was measured using a 3 mm strain gage cemented on the sheet surface nearest to the toe. Data were discussed by nominal stress as well as by local strain.

Cleaner steels, advanced manufacturing techniques and the use of modern design methods have justified an increase of dynamic load ratings for cylindrical and tapered roller bearings as well as ball bearings. With the new load ratings, greater emphasis must be placed on the operating factors that influence the fatigue life of a bearing. These factors include reliability, material, lubrication, alignment and load distribution. A detailed discussion of load rating increases and the life adjustment factors is presented.

The aim of this paper is to demonstrate the methodology to simulate the induced stresses/strains due to thermo-mechanical loading of automobile brake drum.. The brake drum undergoes mechanical load due to applied brake pressure and thermal load due to friction generated between brake pad and brake drum while brake is applied. This coupled thermo-mechanical loading affects the life of the brake drum as the stiffness of the brake drum is reduced. The conventional method of simulating this problem is done using Lagrangian discretization in which the load is applied and inertia effect due to angular velocity is applied to a drum at static condition. In contrast, in this paper Eulerian discretization is adopted for finite element analysis, in which drum brake model is discretized as spatially dependent that facilitates actual rotation of brake drum with simultaneous application of brake load resulting more precise simulation.

Cyclic loading is defined as external loading that varies within the revolution of a bearing and is repeated for every revolution. The cyclicly varying loads may consist of a series of discrete loads that occur in a repeating pattern or a continuously varying force or a combination of these. A simple example of cyclic loading is a single cylinder, double acting piston pump in which the force on the bearings reverses every 180° of a revolution; as a result, the same half of the rotating bearing race passes under the load twice in a single revolution. More complex patterns of cyclic loads occur in rotary engines, fuel injection pumps, nutating engines, etc. The paper presents the theoretical relationships and methods that predict the effect of cyclic loading on the fatigue life of anti-friction bearings. An example problem solved with the aid of a special analysis program illustrates the results from these methods.

Tractors are the self-propelled vehicle which finds its major application in agriculture, haulage and construction equipment. The product development cycle time of a tractor is more as compared to automobiles since it has to undergo rigorous field testing. Bringing more realistic component and system level validation in the test lab will drastically reduce the product development cycle time. Non-availability of standard usage pattern and customer-correlated proving ground pose a bigger challenge for bringing the field conditions to the lab. As a result, the tractor has to be instrumented with sensors and load-time history needs to be acquired as per real world usage pattern. Raw data from the field cannot be used directly for lab testing since the number of load cycles will be very high. Raw data have to be edited based on damage calculation and fatigue sensitivity analysis technique.