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The present paper addresses an investigation about the definition of a parameter for quantifying the creep-groan propensity in brake pads. Creep-groan is a self-excited vibration caused by stick-slip phenomenon [1, 2, 3]. For the definition of the creep-groan propensity parameter, extensive experimental work was performed on a laboratory-scale tribometer. The experiments are divided in two main parts: (i) study of correlation between accelerometer signal with physical and operating parameters. (ii) validation of the chosen parameter, which was based on stick-slip tests performed with three different materials, one low-metallic (low-met) and two non-asbestos organic (NAO 1 and 2). From the first study, it was found that both the slip power and mean torque multiplied by torque variation showed a slightly higher correlation with the acceleration signal.

One effect which is present in drum and disc brakes is the temperature. This effect significantly changes the vehicle and semi-trailer combinations performance, mainly in drum brakes that is more susceptible to this factor. High temperatures mean loss of efficiency, higher lining wear, brakes and rolling systems components life reduction and could be caused by many factors, which can be mentioned, overload, error in design and choice of brake system, speeding, over adjustment (dragging) and environment heat exchange. The challenge is to comprehend the relation between different brake configuration and how these configurations affects the temperatures generation on brake system, allowing that this factors can be evaluated during the project design. This paper aims to show a case study for a new brake family to be used in city bus application where the fleets are looking for better, safety, performance and low lining wear reduce the to increase the maintenance time.

In engineering development, simulation methods are frequently used to perform thermal and mechanical stress components analysis. In brake systems, where the components are exposed to mechanical and thermal loads, the numerical analysis is very helpful. Once a numerical model for brake assembly is available, it will be possible to understand the effects of successive brake applications on the temperature distribution in drum brake's friction materials. This is a fundamental aspect to determine, for instance, the thermal stress distribution which is related to the warming and cooling of the brakes. In this work, an analytical solution to calculate stabilized temperature was used to establish a heat flux through a pneumatic S cam drum brake's friction material applied to a numerical model in a finite element analysis.

Strength and durability of commercial vehicle structure is of prime importance to users while quicker time to market and least material cost are demands of competitive world. This requires assessment not just with simplistic loadcases but robust and accurate predictions closely co-relating real proving ground conditions. This paper demonstrates systematic approach of first road load predictions using MBD model, then stress analysis using FE model and finally life prediction using fatigue solver. MBD model was built using flex body, air suspensions with rigid links and tires with FTire characteristics. Same model ran on various virtual proving grounds and load history at various joints were extracted. Then inertia relief stress analysis with unit loads were carried out in Nastran and output stresses were mapped against load history in fatigue solver.

Reliable sealing solutions are extremely important in commercial vehicle industry because sealing failures can cause vehicle breakdown, damage of equipment or even accident, incurring expenses that are substantially higher than the costs of just replacing the damaged seals. Consequently, new seal designs must be experimentally verified and validated before they can be implemented. In this study, Mooney - Rivlin hyper elastic material model is used to simulate the sealing behavior during dynamic conditions. The seal under study is a large diameter lip seal made of Neoprene® rubber (NBR) A finite element model to study the response of the seal under dynamic conditions was developed. The analysis took into account the mating parts dimensions and the lip seal parameters. Three designs were proposed and verified. The seal design is optimized using non-linear FEA and validated. Results include contact pressure, deflection and strain experienced by the seal during actuation.

The search for better energy efficiency is leading the developments in automotive industry, looking for opportunities to reduce losses, optimizing the design and getting better efficiency of every component. This paper will present a non-linear dynamic study of interaction between commercial vehicle and the environment, considering all the influence of their dynamic characteristics in the fuel consumption. The first step is to analyze all variables that influence the dynamic behavior and then construct a mathematical model based on energy and based on forces (Newton). The interaction between the vehicle and its environment and the response of it will be considered as influent aspects and should be included into vehicle dynamic modeling.

The several problems and bottlenecks faced users public transport users in big cities are a common knowledge. Among them agencies responsible for public transport recognize the lack of centralized control, the under and over supply, the lack of information to users and the non-compliance of scheduled trips. In order to work identified problems improving cities like Recife and São Paulo are testing systems named as embedded technology that integrate the use of GPS, cameras, centralized monitoring among others, retarding a deeper coverage compared to systems previously used. The main objectives are the comfort and safety increase of users and the freight logistics improvement. This paper presents the technologies being tested in Brazil through successful models applied in countries as Spain and Colombia, as well as the scope of bids and proposals for improvement of public transport.

In order to achieve the best automotive vehicles, companies seek for innovation and new technologies to improve their vehicles. Lately the embedded electronic has been used to add intelligence to a purely mechanical systems. The reduction of fuel consumption, one of the biggest concerns of automotive engineering, for the last couple of years, depends on many factors. Some those factors are engine type, fuel quality, vehicle load, gearshift pattern, vehicle usage, driver behavior and the cooling system technology. The fan applied in cooling system uses part of engine power to run, influencing the fuel consumption and contributing to the global noise level of vehicle, being directly associated with passenger’s comfortable. One alternative in study is the use of a set of electric fans that can be triggered independently, in order to increase the heat exchange in specific places of radiator, while reducing the noise and run time.

Vehicle durability mission loads are an essential and decisive for a reliable life prediction for the component through any durability evaluation. One option to calculate mission loads are multibody models to represent vehicle’s suspension degrees of freedom (dofs) and its dynamic behavior. Generally, trucks have greater wheelbase and then lower natural frequencies than passengers’ vehicles. Therefore are more suitable to dynamic body excitation and the ordinary consideration of a rigid body shell is not relevant. The proposal of this work is to compare the chassis loads considering rigid and flexible frame mounted over the primary suspension. A pseudo-damage was calculated with chassis loads time history for severity assessment. The chose vehicle for the study is an Iveco 4×2 medium range, 6850mm of wheel base, with gross weight of 17ton and leaf springs primary suspension on both: front and rear axles.

Durability tests of commercial vehicles are performed on road running uphill and downhill as well as on flat roads; these tests take very long time and have high costs. To lower test time and costs, it is proposed to accelerate the durability tests of commercial vehicles power trains by using a Towing Trailer with an electromagnetic (EM) brake, developed in Brazil, simulating uphill. This Trailer was already presented [1], [2] for cooling test simulation at 20 km/h on commercial vehicles up to 250 HP. In the cabin (cab) of the vehicle under test, there are the braking level control and a laptop, which receives wireless and registers the operational parameters of the Towing Trailer. The GPS in the truck cabin (cab) supply information such as time, speed, latitude and longitude allowing the control of the route.

The proposed paper establishes a standard for load control of the air conditioning system and leak detection, for Trucks, Tractors, Harvester, Sprayers and Construction Machines. Also develop tests to measure the performance of air conditioning system in product audits. These processes are focused on mass production and not for repairs. The target, is establish an parameter objectively, for the comfort conditions offered by air conditioning systems, because the field claims, generally are subjective. All test and controls are designed for, ecologic fluid. R-134a In this paper, parameters are shown to directly control, the comfort provided by the air conditioning system of Agricultural Equipment, Construction and Industrial Vehicles, taking measurements of temperature inside the cabin and ambient conditions. Also, we have indirect parameters, for comparison with the internationally established comfort zones by ASHRAE organization for inside a cabin.

Due to the increasingly stringent emissions standards in the world and, on the other hand, the foreseen shortage of fossil fuels, the application of low viscosity engine oils (LVO) is considered one of the most interesting options for counter these threats. In parallel to a fuel consumption fleet test, the aim of this study was to assess the performance of commercial low viscosity oils regarding their degradation and engine wear, since the use of LVO could imply an increase in wear rate. Potential higher engine wear could result in a reduction in the expected engine life cycle, obviously is a non-desired effect. In addition, currently limited data are available regarding “real-world” performance of LVO in a real service fleet.

Advancement in Heavy Duty Diesel Engine Oils has, for approximately two decades, been driven by the ever more stringent emission legislation for NOx and Particulates. Over the last few years, the focus has shifted to reducing CO2 emissions, which created an interest in fuel efficient lubricants. In addition, increased fuel cost and a need to control operational expenses in a weaker economy have further heightened the interest in fuel efficient lubricants. Where the trucking industry was reluctant to move away from the tried and true SAE 15W-40 viscosity grade, there is now a strong interest in pushing the boundaries of lower viscosity to reduce internal friction in the engine and thereby improve fuel efficiency. Consequently, the industry is exploring and introducing lower viscosity grades, such as SAE 10W-30 and even SAE 5W-30.

This paper shows the results of a fuel consumption in-use comparison test where the effect of Low Viscosity Oils (LVO) was evaluated over a sample of 39 urban buses powered by Diesel and CNG engines. The aim of the test was to verify the fuel consumption benefits of LVO in Heavy Duty Vehicles (HDV) found in previous works, which were obtained mainly in engine test bench, when engines are working on “on-Road” conditions. In order to achieve this goal, a sample of 39 urban buses was studied over an Oil Drain Interval or 30.000 km (approximately an 11 month period), measuring daily mileage and fuel consumed to calculate each bus fuel consumption. Mileage was measured by GPS and fuel consumed was measured from refueling system. The sample was divided into two groups; a control group of buses using reference oils (SAE grade viscosities of 15W-40 and 10W-40) and a candidate group using LVO oils (SAE grade viscosities 5W-30).

Off-road BS III CEV (US-TIER III equivalent) emission regulations for diesel engines (i.e. Construction Equipment Vehicles) in India demands a technology upgrade to achieve a large reduction in NOx (>50%) and Particulate Matter (>50%) compared to BS II CEV emission levels. EGR is a widely accepted technology for NOx reduction in off-road engines due to lower initial and operating costs. But EGR has its own inherent deficiency of poor thermal efficiency due to lack of oxygen and further increase in soot adding complexity of meeting PM Emissions. Hence an engine meeting BS III CEV norms without EGR/SCR technologies with low initial investment is most desired solution for Indian off-road segment. This work deals with the development of an off-road diesel engine rating from 56 to 74 kW, focused mainly on in-cylinder optimization with the aid of optimum injection and charging strategies.

This study deals with the development of an internal EGR (Exhaust Gas Recirculation) system for NOx reduction on a six cylinder, turbocharged intercooled, off-road diesel engine based on a modified cam with secondary lift. One dimensional thermodynamic simulation model was developed using a commercially available code. MCC heat release model was refined in the present work by considering wall impingement of the fuel as given by Lakshminarayanan et al. The NOx prediction accuracy was improved to a level of 90% by a generic polynomial fit between air excess ratio and prediction constants. Simulation results of base model were correlating to more than 95% with experimental results for ISO 8178 C1 test cycle. Parametric study of intake and exhaust valve events was conducted with 2IVO (Secondary Intake Valve Opening) and 2EVO (Secondary Exhaust Valve Opening) methods. Combinations of different opening angles and lifts were chosen in both 2IVO and 2EVO methods for the study.

An analysis method to study the potentials of recovering the brake energy from Volvo articulated haulers has been developed. The study has been carried out with purpose to find out how and where possible hybrid solutions can be used. The method is based on the mapping of the peak brake power, brake energy and engine energy. This method was developed using adequate signals collected on haulers at three different customer sites. A conceptual study was also carried out concerning the brake energy to understand the actual amount of brake energy that may be stored in an Energy storage system (ESS). The results indicate that the analysis method developed can map the brake energy generated and also provide an overview of the actual amount of brake energy that can be accumulated in an ESS. Hence, the method may also providing guidelines regarding the selection of an ESS for a particular work site.

High-strength steels are a cost-efficient means of reducing the weight not only of premium-segment cars but also of light, medium and heavy commercial vehicles. Lighter a vehicle, lower its fuel consumption and the lower its CO2 emissions during driving. Depending on part and use, high-strength steels permit weight savings of up to 30 percent. In this way steel makes a key contribution to sustainable mobility. Innovative high-strength steels allow auto components to be made thinner and thus lighter without sacrificing safety. A wide range of application oriented automotive grades have been developed at SAIL. Despite their high strength, these materials are readily formable and can be processed without difficulty at auto stamping plants. The challenge with these materials is that high strength and good formability are usually mutually exclusive. This conflict is resolved with solutions such as special alloying elements.

Tubular stabilizer bar for commercial vehicle is developed using advanced high strength steel material. Tubular section is proposed to replace the existing solid section. The tubular design is validated by component simulation using ANSYS Software. The tubes are then manufactured of the required size. The bend tool is designed to suit the size of the profile stabilizer bar and the prototypes are made using the tube bending machine. The strength of the tubular stabilizer is increased by using robotic induction hardening system. The tubular stabilizer bar is tested for fatigue load using Instron actuators. Higher weight reduction is achieved by replacing the existing solid stabilizer bar with the tubular stabilizer bar.

Light weighting is an increasingly important objective for auto manufacturers. Every gram of weight saved reduces CO2 emissions and thus makes the vehicles eco-friendlier. The reduction in sheet thickness by use of high strength steel is being increasingly adopted as an effective means for weight reduction, because of cost savings. The exhaustive research analysis by ULSAB (Ultra-Light Steel for Auto Body) /ULSAC (Ultra-Light Steel for Auto Concept) has demonstrated that steel is the only material suited to meet the conflicting demands of properties required for the auto applications and offers the possibility of weight saving potential and increased payload. ESSAR steel recognizes the need for stringent product needs for the increasing demands in the new scenario of increasing globalization and design of new generation world platforms.