Fuel economy is becoming one of the key parameter as it not only accounts for the profitability of commercial vehicle owner but also has impact on environment. Fuel economy gets affected from several parameters of engine such as Peak firing pressure, reduction in parasitic losses, improved volumetric efficiency, improved thermal efficiency etc. Compression ratio is one of key design criteria which affects most of the above mentioned parameters, which not only improve fuel efficiency but also results in improvement of emission levels. This paper evaluates the optimization of Compression ratio and study its effect on Engine performance. The parameters investigated in this paper include; combustion bowl volume in Piston and Cylinder head gasket thickness as these are major contributing factors affecting clearance volume and in turn the compression ratio of engine. Based on the calculation results, an optimum Compression Ratio for the engine is selected.
In sheet metal painting for various applications like Tractor, Automobile, most attractive coating is metallic paints and it is widely applied using 3 coats 2 bake or 3 coat 1 bake technology. Both options, results in high energy consumption, higher production throughput time & lower productivity in manufacturing process. During various brainstorming & sustainable initiatives, paint application process was identified for alternative thinking to reduce burden on environment & save energy. Various other industry benchmarking & field performance requirement studies helped us identify the critical to quality parameters. We worked jointly with supplier to develop mono-coat system without compromising the performance & aesthetical properties. This results in achieving better productivity, elimination of two paint layers, substantial reduction in volatile organic content, elimination of one baking cycle and energy saving.
Rocker arm in internal combustion engine is very important part which transfer the cam motion and force to the valve. In heavy commercial vehicles, the engine components are design for an infinite life (considerable higher than other components). Recently industries are working for light weight and optimized cost material. Hence it is required to have an optimized cost effective design of rocker arm without affecting its performance. A rocker arm should meet the stiffness and strength requirement. The objective of this study is to find out the alternate material for rocker arm which can provide the similar strength & stiffness as conventional rocker arm material. To achieve the performance and cost target, alternate material cast iron has been evaluated for rocker arm. Cast iron is lighter than the forged steel rocker arm, also it has a good frictional characteristic. Further bush is eliminated from the rocker arm assembly due to self-lubricant property of the cast iron rocker arm.
The increasing demand for light weighting products due to introduction of various standards and norms for controlling CO2 emissions and to meet the customer requirement of low cost with higher strength and rigidity of product in automotive industry, sheet metal manufacturing technique is adopted for automotive steering yoke for light commercial vehicle. Currently forged yokes are used for higher strength requirement, while sheet metal yokes are being used for small tonnage vehicle. The attempt has been made to improve overall strength and rigidity of the yoke produced by sheet metal operation using SAPH 440 steel with 6.5mm thickness for light commercial vehicle segments. The major challenge identified for this development was developing such a high strength and thickness material with consistency of dimension during forming process and meeting the torsional strength requirement of 500 Nm.
Abstract Electric heavy-duty tractor-trailers (EHDTT) offer an important option to reduce greenhouse gases (GHG) for the transportation sector. However, to increase the range of the EHDTT, this effort investigates critical vehicle design features that demonstrate a gain in overall freight efficiency of the vehicle. Specifically, factors affecting aerodynamics, rolling resistance, and gross vehicle weight are essential to arrive at practical input parameters for a comprehensive numerical model of the EHDTT, developed by the authors in a subsequent paper. For example, drag reduction devices like skirts, deturbulators, vortex generators, covers, and other commercially available apparatuses result in an aggregated coefficient of drag of 0.367. Furthermore, a mixed utilization of single-wide tires and dual tires allows for an optimized trade-off between low rolling resistance tires, traction, and durability.
This procedure provides test performance requirements for service, spring applied parking, and double diaphragm combination air brake actuators with respect to durability, function, and environmental performance when tested in accordance to SAE J1469.
This SAE recommended practice provides procedures and methods for testing service, spring applied parking and combination brake actuators for air disc brake applications. Methods and recommended samples for testing durability, function and environmental performance are listed in 1.1 and 1.2.
This SAE Standard covers specifications and performance requirements for 37° and 45° single and double flares for tube ends intended for use with SAE J512, SAE J513, SAE J514, and ISO 8434-2 connectors. The flares described in this document are intended for use with SAE metallic tube materials. Considerations such as the effects of wall thickness selection for specific working pressures, identifying appropriate length of thread engagements for specific applications with mating connectors and other associated criteria, shall be the responsibility of the user. For applicable nominal reference working pressures for hydraulic tubing, see SAE J1065 and ISO 10763.
In view of the current political debate, it can be assumed that the nitrogen oxide limits for commercial vehicles will be further reduced. This is also demonstrated by the currently voluntary certification of the CARB Optional Low NOX legislation, which requires nitrogen oxide emissions of 0.027 g/kWh. This corresponds to a reduction of 93 % compared to the current EU VI standard. Therefore, the optimization of EAT systems represents an essential research focus for future commercial vehicle applications. One way to optimize the EAT system may be the usage of variable valve actuation. Existing investigations show an exhaust gas temperature increase with intake valve timing adjustment, also known as Miller timing. But the authors conclude that it cannot accelerate the warm up process. With regard to the effects on the exhaust aftertreatment system and the resulting tailpipe emissions, only improved HC and CO oxidation could be identified so far.
In this paper, a numerical and experimental assessment of post injection potential for soot emissions mitigation in an off-road diesel engine is presented, with the aim of supporting hardware selection and engine calibration processes. As a case study, a prototype off-road 3.4 liters 4-cylinder diesel engine developed by Kohler Engines was selected. In order to explore the possibility to comply with Stage V emission standards without a dedicated aftertreatment for NOx, the engine was equipped with a low pressure cooled Exhaust Gas Recirculation (EGR), allowing high EGR rates (above 30%) even at high load. To enable the exploitation of such high EGR rates with acceptable soot penalties, a two-stage turbocharger and an extremely high-pressure fuel injection system (up to 3000 bar) were adopted. Moreover, post injections events were also exploited to further mitigate soot emissions with acceptable Brake Specific Fuel Consumption (BSFC) penalties.
This paper deals with the experimental and numerical investigation of a 2.0 litre single cylinder Heavy Duty Diesel Engine fuelled by natural gas and diesel oil in Dual Fuel mode. Due to the gaseous nature of the main fuel and to the high compression ratio of the diesel engine, reduced emissions can be obtained. An experimental study has been carried out at three different load level (25%, 50% and 75% of full engine load). Basing on experimental data, the authors recreated a 45° mesh sector of the engine cylinder and performed CFD simulations for the cases at 50% and 75% load levels. Numerical simulations were carried out on the 3D code Ansys FORTE. The aim of this work is to study combustion phenomena and, in particular, the interaction between natural gas and diesel oil, respectively represented by methane and n-dodecane. A reduced kinetic scheme for methane auto-ignition was implemented while for n-dodecane two set of reactions were utilised.
Natural gas (NG) is an alternative fuel for spark-ignition engines. In addition to its cleaner combustion, recent breakthroughs in drilling technologies increased its availability and lowered its cost. NG consists of mostly methane, but it also contains heavier hydrocarbons and inert diluents, the levels of which vary substantially with geographical source, time of the year and treatments applied during production or transportation. To investigate the effects of NG composition on engine performance and emissions, a 3D CFD model of a heavy-duty diesel engine retrofitted to NG spark ignition simulated lean-combustion engine operation at low speed and medium load conditions. The work investigated three NG blends with similar lower heating value (i.e., similar energy density) but different Methane Number (MN). The results indicated that a lower MN increased flame propagation speed and thus increased in-cylinder pressure and indicated mean effective pressure.
SAE J1362 presents graphical symbols for use on operator controls and other displays on off-road work machines as defined in SAE J1116 plus mobile cranes but excluding agricultural tractors. Symbols for agricultural tractors are covered by ASABE S304, ISO 3767-1, and ISO 3767-2.
This SAE test method establishes a uniform test procedure for determining the gravimetric (mass based) efficiency and pressure drop performance levels of operator enclosure panel type filters on off-road, self-propelled work machines used in earth moving, and forestry, as defined in SAE J1116 and for agricultural equipment as defined in ANSI/ASAE S390, and equipped with an operator enclosure with a powered fresh air system. ISO/TS 11155-1 may additionally be used, which describes the use of particle sizing devices to measure the fractional (particle size) efficiency of panel type filters for automotive cabin filter applications. Automotive cabin filters are similar to filters described in this procedure, and the ISO/TS 11155-1 test method is therefore directly applicable.
Abstract Three-dimensional patterns representing crosshatched plateau-honed cylinder bores based on two-dimensional Fast Fourier Transform (FFT) of measured surfaces were generated and used to calculate pressure flow, shear-driven flow, and shear stress factors. Later, the flow and shear stress factors obtained by numerical simulations for various surface patterns were used to calculate lubricant film thickness and friction force between piston ring and cylinder bore contact in typical diesel engine conditions using a mixed lubrication model. The effects of various crosshatch honing angles, such as 30°, 45°, and 60°, and texture heights on engine friction losses, wear, and oil consumption were discussed in detail. It is observed from numerical results that lower lubricant film thickness values are generated with higher honing angles, particularly in mixed lubrication regime where lubricant film thickness is close to the roughness level, mainly due to lower resistance to pressure flow.