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This paper presents a numerical study of air filters used for an off-highway vehicle by using commercial CFD code FLUENT v 6.1. For the primary filter, the flow is obtained by the use of Reynolds stress model and stochastic Lagrangian model is used to study the gas solid flow. The separation efficiency for dust particles of sizes 50 and 100 microns is found to be 94.4 %. For the secondary air filter, filter portion is modeled as equivalent porous medium. The pressure drops obtained by the analysis agrees very well with the experimental results. The convective scheme is found to have little effect on the prediction of pressure drop through the secondary filter.

Design of an efficient cooling system for new generation engines has become a critical task, which requires to be handled optimally at the design stage itself. This approach helps in minimizing the optimization trials, saving time and cost for finalization of patterns and castings. Study of water jacket core in the engine cylinder head and block is of complex nature. Shape, size and location of transfer holes play a vital role in judging the eddies formation and hot spots. It is required to eliminate the hot spots, thus improving cooling efficiency and durability of the component. Use of CFD technique is found to be an effective design tool while dealing with such kind of complex flow problems. In this paper, effective utilization of FIRE CFD code is described for water jacket design of a modular two-cylinder diesel engine being developed from scratch.

The heavy commercial vehicles are equipped with under-run protection devices (UPD) to enhance safety of occupants in small vehicles in the event of under-run. These UPD are popularly classified as RUPD (rear under-run protection devices), SUPD (side under-run protection devices), FUPD (front under-run protection devices). These devices primarily work to improve safety of smaller vehicles by changing its interaction with heavy vehicles thereby resulting in change in small vehicle structural engagement for energy absorption. Without UPD, smaller vehicle passenger compartment is likely to interact with stiff commercial vehicle chassis frame structures. However with UPD, the smaller vehicle front-end structure gets involved in the crash which helps in controlled energy absorption and safe-guards the passenger compartment.

As a means of lowering greenhouse gas emissions, increasing economic growth, and reducing the dependency on imported oil, the Department of Energy and Brookhaven National Laboratory (DOE/BNL) is promoting the substitution of liquefied natural gas (LNG) in heavy-vehicles that are currently being fueled by diesel. Heavy vehicles are defined as Class 7 & 8 trucks (> 118,000 pounds GVW), and transit buses that have a fuel usage greater than 10,000 gallons per year and driving range of more than 300 miles. The key in making LNG market-competitive with all types of diesel fuels is in improving energy efficiency and reducing costs of LNG technologies through systems integration. This paper integrates together the three LNG technologies of: (1) production from landfills and remote well sites; (2) cryogenic fuel delivery systems; and (3) state-of-the-art storage tank and refueling facilities, with market end-use strategies.

A dedicated closed-loop propane fuel system has been developed for the General Motors Medium Duty truck with a 7.4 liter engine. The fuel metering system consists of a closed-loop controlled regulator and mixer. Regulator output pressure is controlled by a pulse-width modulated vacuum signal from the mixer for off-idle operation. Idle fuel is provided by an electronically controlled, fuel metering solenoid valve. Additionally, original equipment manufacturer (OEM) fail-safe performance of the Electronic Throttle Control system has also been achieved. This fuel system is an example of how an open loop regulator-mixer system can be enhanced with electronic controls to achieve significant improvements in emission signature, driveability, and customer satisfaction.

Early experience with precision farming technology suggests that some hardware and software may follow a rapid S curve adoption path, but that the use of integrated precision farming systems may take longer to develop and be subject to false starts and periods of stagnation. Yield monitors appear to be following a classic S curve adoption path. Precision farming adoption is like that of hybrid corn because changes in organizations will be required to use it effectively. It is like motorized mechanization because it is coming on the market in an immature form and lends itself to farmer tinkering.

Bubbles in working fluids have much influence on the performance of fluid power systems. One of the authors has developed a novel device for bubble elimination capable of eliminating bubbles and decreasing dissolved gases using swirl flow. In this paper, performance of bubble removal in oil flow is studied through numerical analysis of the swirl flow in the device. This paper also documents a reduction of oil temperature rise and removal of entrained air from the working fluid in the hydraulic circuit by use of the device. It has been confirmed that the device is effective keeping the oil temperature low in the fluid power system.

Cavitation is a common and usually undesirable phenomenon in hydraulic systems. Understanding the basics of cavitation phenomenon as well as detecting existing cavitation are important in order to prevent cavitation in hydraulic systems. In this paper past studies of orifice cavitation are discussed and also new studies of orifice and valve cavitation with hydraulic oils are presented. Cavitation behaviour of different kinds of orifices and a poppet valve have been studied. Studies were done with different cavitation numbers. Rough design guidelines for reducing and preventing cavitation in orifices and valves are presented.

Precision agriculture technologies and systems will significantly change food and fiber production as we move into the next century. Engineers have and will continue to contribute to this field through development of equipment and sensors, application of technologies such as remote sensing and computer modeling, creation and evaluation of precision agriculture systems, and management of technology development and implementation activities. Realization of the potential benefits of precision agriculture -- including both improvements in production efficiency and achievement of water, air, and soil environmental quality goals -- will require a partnership between engineering and other disciplines in both industry and the public sector.

The problem of fuel consumption decrease in agricultural machinery may be addressed in several ways. One is to equip mobile agricultural machines (tractors, harvesters, sprayers, fertilizer spreaders, etc.) with on-board computers (BC) capable to measure the fuel flow rate, in particular, which will allow to decrease fuel consumption by these machines due to timely control of the technical conditions of the engine and optimization of the machine operation modes from the point of view of fuel consumption. The article describes a family of diaphragm chamber fuel flow transducers (FFT) for on-board computers of mobile agricultural machines, gives their technical characteristics and laboratory and field test results, and recommendations on connecting them to engines of various power specifications.

Design analysts, who work with finite element shape optimization, face a daunting task of handling cylindrical parts like a pusher for a crimp. The shape vectors generated by any of the existing methods/tools cannot constrain nodes to move in a circular path. Since the pusher is not a complete cylinder and the loading is only along axial direction, shape optimization was performed after flattening out the cylindrical pusher. The existing shape optimization tools could now be applied to the flat plate. A numerical interpolation method, based on ‘Autodv’, has been used to generate shape vectors. Both weight and stresses have been brought down and the final design was verified with solid finite element analysis.

Valve blocks are the key parts in hydraulic systems. A feature-based product model is the foundation of the CAD/CAM system for valve blocks--VBCADAM. This paper mainly analyses the design procedure of valve blocks, the application of feature-based design and modeling, object-oriented approach in the development of VBCADAM, such as feature definition and classification, the frame description of features, structure of product model and also the application of the product model in VBCADAM.

Heavy-duty vehicles account for approximately 30 percent of the oxides of nitrogen (NOx) and 65 percent of the particulate matter (PM) emissions from the entire California on-road fleet, despite the fact that these vehicles comprise only 2 percent of the same. To meet legislative mandates to reduce excess smoke emissions from in-use heavy-duty diesel-powered vehicles, the Air Resources Board (ARB or Board) adopted, in December 1997, amendments to the regulations governing the operation and enforcement of the Heavy-Duty Vehicle Inspection Program (HDVIP or the “roadside” program) and the Periodic Smoke Inspection Program (PSIP or the “fleet” program). The initial roadside program was adopted in November 1990 in response to Senate Bill (SB) 1997 (stat. 1988, ch. 1544, Presley), and enforced from 1991 to 1993. It was suspended in October 1993, when the Board redirected staff to investigate reformulated fuels issues.

Lasershotsm peening, a surface treatment for metals, is known to induce compressive stresses of over 0.040 in. This provides a damage tolerant component more resistant to various forms of stress related failures than more traditional forms which induce residual compressive stress. This process developed in the 1970's has now moved from a laboratory curiosity to an affordable process for industry. We have developed a unique solid state laser technology employing ND:glass slabs and phase conjugation that enables this process to move into high throughput.

Many existing electronic controls used in hydraulic systems utilize a microcontroller with associated electronic drive buffer and multiple closed loop feedback paths. One of the common feedback paths is through sensing the electrical current supplied to the solenoid for the proportional valve. Use of pulse-width-modulation (PWM) is typically utilized to minimize power dissipation in the electronic drive buffer and to facilitate integration with the microcontroller.

A distributed sensor is created to sense the rate of change in deflection of beam-like structures such as crane booms. This sensor will be useful in electrohydraulic compensation of boom deflections. The sensor is made of an array of strain-sensitive segments such as strain gages or piezoelectric film. In this example, segments of piezoelectric film convert strains on the surface of a vibrating beam into electrical outputs. These outputs are connected to low impedance signal conditioners. The output of the signal conditioners are then interpolated with a weighting vector that incorporates Lagrange polynomials, specified boundary conditions, and the desired location(s) of measurement. A simple linear combiner circuit combines the electrical outputs into the deflection velocity at the desired points.

Most fertilizer application systems are not capable of variable rate adjustments “on-the-fly”. To change the application rate, the farmer must dismount the tractor and change the gear ratio mechanically (i.e. via gears, chains, etc.). Air seeder manufacturers have come up with their own unique solutions to address this problem, usually involving electrohydraulics. At present there are older seeding units that perform adequately, but do not have the variable rate option. A retrofit is therefore very desirable for these units. In this paper, the feasibility of a simple hydraulic proportional valve and variable speed motor circuit is employed to replace the gears and chains. The unit is integrated with a microcontroller to provide compensation to the nonlinear properties of a proportional valve, and in turn provide a very accurate feedrate. In addition, direct user input from the cab of the tractor is possible, allowing on-the-go rate changes.

In mobile hydraulics pilot valves control pumps, motors and main stages. An influencing factor regarding the use of these valves is compact dimensions, which are realised in combining solenoids with the control pressure stage. Applied electrical power together with the corresponding pressure level will be explained in this presentation by showing two types of Proportional Pressure Reducing Valves (PPRV's). One will be a PPRV for various operating pressure levels and the other a High-Flow PPRV (HFPPRV) for high volume flows. Descriptions of function, design solutions, features and manufacturing techniques will follow as well as application of integrated electronics and simulation of solenoids.

There is a critical need for improved processes and systems mobility product life cycles and application of these improvements to vehicles on a global basis. As products expand to reach global markets, the need for globally harmonized test procedures, specifications and standards increase dramatically. According to Keith Termaat, Ford Motor Company, “as competitve and regulatory forces become increasingly global - worldwide standards development and deployment are essential for corporate survival.” The critical issue facing all Standards Developing Organizations (SDOs) will be facilitating this transformation quickly and efficiently and in a manner that will allow the automotive industry to expand into the global marketplace.

This paper will cover the importance of certification to individuals in the fluid power industry as well as the importance to industry in general. Fluid power is a world player in power transmission yet it is not a part of our school system curriculum. As an aid to remedy this the Fluid Power Society has developed a certification program with review training to establish several “benchmarks” that are recognized by industry nationally and internationally. The procedures for establishing fluid power certification have been approved by the American National Standards Institute and the Federal Government Department of Occupational titles has approved all the job descriptions.