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.
Hydraulic power train assembly of an agricultural tractor is meant to controls the position and draft of the implement depending upon the type of crop, farming stage, implement type and soil conditions. These variations induce extreme range of loads on the hydraulic system, thus making it challenging to design these components. Hydraulic connecting rod is critical component of hydraulic power train assembly. Standards like IS12224, IS4468 governs the design of hydraulic power train components which regulates the test method for hydraulic power and lift capacity of the tractor. In this paper, a virtual simulation process has been established to design a hydraulic connecting rod to meet the requirements. The hydraulic connecting rod basically functions as a short load transferring link, which is subjected to the operating hydraulic pressure of the hydraulic lifting mechanism. The current circular connecting rod is higher in weight and cost.
Future emission limits for off-highway application engines need advanced power train solutions to meet stringent emissions legislation, whilst meeting customer requirements and minimizing engineering costs. Development of diesel engines for off-highway application for different power segments need different intake port design solutions to optimise in-cylinder flow structure for efficient combustion. With adaptation of low pressure mechanical fuel injection system, intake port development becomes an important stage for reduction of emission formation at the source and improvement in fuel economy. In this paper, intake port design and development process is elaborated for two different power ratings of 75 hp and 120 hp of off-highway engine. 2-valve and 4-valve configurations are deployed for the same cylinder bore size.
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.
This SAE standard includes hydraulic backhoes which have no more than 190 degrees of rotational swing and are mounted on wheeled tractors and crawler tractors. Illustrations used are not intended to include all existing commercial machines or to be exact descriptions of any particular machine. The illustrations have been chosen to describe the principles to be used in applying this standard.
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 SAE Standard applies to mobile, construction-type lifting cranes of the cantilever boom type (Figure 1). Questions and comments regarding application or interpretation of the provisions in this test method should be referred to the originating SAE Committee.
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.
A raise of efficiency is the strongest selling point concerning the total cost of ownership (TCO), especially for commercial vehicles (CV). Accompanied by legislations, with contradictive development demands, satisfying solutions have to be found. The analysis of energy losses in modern engines shows three influencing parameters. Wall heat transfer (WHT) losses are awarded with the highest optimization potential. Critical for the occurrence of these losses is the WHT, which can be described by representing coefficients. To reduce WHT accompanying losses a decrease of energy transfer between combustion gas and combustion chamber wall is necessary. A measurement of heat fluxes is necessary to determine the WHT relations of the combustion chamber in an engine. As this has not been done for a Heavy-Duty (HD) engine, with peak pressures up to 250 bar, an increased in-cylinder turbulence and high exhaust gas recirculation (EGR)-rates before, it is presented in the following.
The recuperated split cycle engine is a fundamentally new class of internal combustion engine that offers a step change in thermal efficiency over conventional Otto and Diesel cycle engines. In a split cycle engine, the compression and combustion strokes are performed in different cylinders. Intensive cooling of the compression stroke by the injection of liquid nitrogen directly into the chamber enables the recovery of waste heat from the exhaust between the compression and combustion cylinders. Brake efficiencies of over 50% have been reported without compression cooling, rising to 60% where the compression stroke is cooled by the injection of liquid nitrogen. The technology targets the heavy duty, long-haul sector where electrification is ineffective. In this paper, results from an experimental program conducted on a single cylinder research engine, representing the combustor cylinder of a recuperated split cycle engine are reported.
Flexible, reliable and consistent combustion models are necessary for the improvement of the next generation spark-ignition engines. Different approaches have been proposed and widely applied in the past. However, the complexity of the process involving ignition, laminar flame propagation and transition to turbulent combustion need further investigations. Purpose of this paper is to compare two different approaches describing turbulent flame propagation. The first is the one-equation flame wrinkling model by Weller, while the second is the Coherent Flamelet Model (CFM). Ignition is described by a simplified deposition model while the correlation from Herweg and Maly is used for the transition from the laminar to turbulent flame propagation. Validation of the proposed models was performed with experimental data of a natural-gas, heavy duty engine running at different operating conditions.
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.
In partially premixed combustion engines high octane number fuels are injected into the cylinder during the late part of the compression cycle, giving the fuel and oxidizer enough time to mix into a desirable stratified mixture. If ignited by auto-ignition such a gas composition can react in a combustion mode dominated by ignition wave propagation. 3D-CFD modeling of such a combustion mode is challenging as the rate of fuel consumption can be dependent on both mixing history and turbulence acting on the reaction wave. This paper presents a large eddy simulation (LES) study of the effects of stratification in scalar concentration (enthalpy and reactant mass fraction) due to large scale turbulence on the propagation of reaction waves in PPC combustion engines. The studied case is a closed cycle simulation of a single cylinder of a Scania D13 engine running PRF81 (81% iso-octane and 19% n-heptane).