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Over the past few years, the determination of blow-by has gained importance. The longevity of measuring equipment has come to play a key role in the measuring of the often oil-contaminated gas and its sticky condensate. Measuring instruments such as gas flow counters, methods based on the Karman vortex street, impeller meters, have a reduced longevity and thus are not suitable for the determination of blow-by where high precision and reproducibility are required. An instrument was developed for measuring blow-by based on the orifice measurement principle. Taking into account the demands placed on a measurement system, we show that this instrument best meets the needs while avoiding the weaknesses of the other measurement methods mentioned above.

A Continuously Variable Cam Phaser (CVCP) used in conjunction with the correct control algorithm can help reduce the negative impact on the environment as well as reduce the energy consumed. Cam phasing has the benefit of improving power and emissions while simultaneously improving fuel economy. This paper will discuss the need for having a good control scheme when using a variable cam phaser and the factors that influence its performance. The paper will outline the factors which affect the cam phaser reaction, and hence the control. The paper will also discuss the importance of using feedback control to properly position the CVCP under dynamic conditions.

Because of the heavy demands placed on today's internal combustion engine bearings, there is an increasing need for quantitative data in the study of bearing performance. To this end a “Scuff/Seizure Test” has been developed which measures seizure resistance, a complex function of conformability and compatibility of the bearing system. Conformability may be defined as the system's ability to accommodate minor geometrical inaccuracies of the sliding surfaces whilst compatibility is the ability of two surfaces to be in contact without system failure. Besides the study of bearing materials the test has been applied to investigate the influences of shaft surface texture and preparation routes.

Certain dynamic methods of testing enable the characterization of elastomeric materials for vibration control in terms of engineering data obtained on fullsized vehicle parts. These dynamic methods are discussed along with several of the traditional rubber test methods currently used in specifying rubber. The discussion emphasizes the usefulness and limitations of the various test methods. Comparisons are made with different elastomers and rubber compounds, showing how the more sophisticated dynamic tests can detect behavior differences, whereas the traditional test methods would have indicated equivalencies. Also, data are shown that correlate actual ride evaluation with dynamic test results.

The purpose of this article is to present the reasons which justify the electromagnetic compatibility (EMC) evaluations used for automotive vehicles. It shows practical experiences of field measurements. Current actions in Brazil to prevent future problems are presented.

Operating in an increasingly competitive market, buses and agricultural equipment are facing the changes that passed trucks and commercial vehicles. Those changes are affecting drastically the final cost of the product and consequently its relationship with the costumer. This constant for more competitive prices drives the companies to develop more aggressive strategies of components standardization on a global level, leading to the emergency of global products in regional applications, keeping regional particularity characteristics when operating in the field. In the bus market, it is confirmed that in various media and academic publications there are recurrent complains about driver comfort by several factors related from the ergonomics of the workplace, as well as with operators from agricultural implements.

Fuel economy benefits derived from improved engine crankcase lubricants have been well documented in the last 10 years. These benefits can be gained not only by a reduction in oil viscosity but also by addition of special friction modifier additives. These have been shown to operate by reducing the friction within the boundary regimes of the engine. Work has been carried out which indicates that a secondary but possibly more significant contribution can be made by friction modifiers where the hydrodynamic regime is extended to lower viscosities. As a result it may be possible to formulate finished lubricants with lowered viscosities while remaining free from wear debits. Such optimised lubricants will result in furtner fuel economy improvements.

The Australian Standard - Methods of test for fuel consumption of passenger cars, their derivatives and multipurpose passenger cars, AS2077-1982 - is based on the method of determining petrol consumption accepted by the United States Environmental Protection Agency. In addition to volumetric and gravimetric fuel measurement techniques, the Standard also allows for the carbon balance method to be used to calculate fuel consumption from exhaust gas analysis data for a vehicle simulating city and highway driving conditions on a chassis dynamometer. Comparison of carbon balance fuel consumption results with data from a fuel flow meter fitted to the vehicle during tests, has shown consistent differences. Fuel consumption from the carbon balance method for hot start city cycle tests averaged 7% lower than volumetric results and 4% lower for the highway cycle.

A large number of vehicles are now running on gaseous fuels. Most are using liquefied petroleum gas (LPG), and some are using natural gas (NG). Published studies have listed the advantages and disadvantages of such conversions, but these have had an unexpected degree of understatement and take a very stringent view of the emission advantage, giving the impression that vehicles using gaseous fuels cannot compete with emission control of the clean gasoline-powered vehicles planned for 1975. This conclusion will probably be proved erroneous when all data are available. As compared to clean 1975 gasoline vehicles, gaseous-fueled vehicles will probably be cheaper to run and more reliable. Disadvantages include limited distribution of gaseous fuels, limited fuel-carrying capacity, some regulatory limitations, and a need for more highly developed hardware. Despite these problems, there is a small but important market where conversion will be very profitable for the owner and the community.

Optimal energy management of hybrid electric vehicles has previously been shown to increase fuel economy (FE) by approximately 20% thus reducing dependence on foreign oil, reducing greenhouse gas (GHG) emissions, and reducing Carbon Monoxide (CO) and Mono Nitrogen Oxide (NOx) emissions. This demonstrated FE increase is a critical technology to be implemented in the real world as Hybrid Electric Vehicles (HEVs) rise in production and consumer popularity. This review identifies two research gaps preventing optimal energy management of hybrid electric vehicles from being implemented in the real world: sensor and signal technology and prediction scope and error impacts. Sensor and signal technology is required for the vehicle to understand and respond to its environment; information such as chosen route, speed limit, stop light locations, traffic, and weather needs to be communicated to the vehicle.

The different roles played by small and large eddies in engine combustion were studied. Experiments compared natural gas combustion in a converted, single cylinder Volvo TD 102 engine and in a 125 mm cubical cell. Turbulence is used to enhance flame growth, ideally giving better efficiency and reduced cyclic variation. Both engine and test cell results showed that flame growth rate correlated best with the level of high frequency, small eddy turbulence. The more effective, small eddy turbulence also tended to lower cyclic variations. Large scales and bulk flows convected the flame relative to cool surfaces and were most important to the initial flame kernel.

The effects of injection variability, low velocity fuel injection, and injector orifice size on unburned hydrocarbon emissions were studied in a direct-injection stratified-charge (DISC) engine. The engine incorporated a combustion process similar to the Texaco Controlled Combustion System (TCCS) and was operated with gasoline. The variability in the amount of fuel injected per cycle was found to have a negligible effect on HC emissions. Changing the amount of fuel injected at low velocity at the end of injection impacted the HC emissions by up to 50%. A positive pressure differential between the injection line and the combustion chamber when the injector needle closed resulted in more fuel injected at low velocity and increased HC emissions. High speed single frame photography was used to observe the end of injection. Injectors with smaller orifices had substantially lower HC emissions than the baseline injector.

Servo hydraulic actuators are generally position controlled, and the position feedback must be calibrated by trained technicians using specialized equipment. When servo hydraulic actuators are replaced for any reason, it is important that the calibration of the internal position feedback of the replacement actuator is close to the original. In addition, conventional methods only permit static calibration of the position feedback. The object of this paper is to show a practical method for checking the position calibration using accelerometers as sensors.

Modern vehicles are expected to operate satisfactorily at relatively low ambient temperatures, often without auxillary heating equipment. At these cold temperatures, the lubricant plays a key role in determining how easily the vehicle can be started, and how quickly all vital moving parts are oiled. A lubricant which is too thick under these conditions may result in poor operability, or in some cases catastrophic equipment failure due to oil starvation. Extensive testing has demonstrated the low temperature performance advantages of SAE 0W-30 or 5W-30 engine oils versus more common SAE 10W-30 and 15W-40 viscosities, in both light and heavy duty engines. Automatic transmission fluids with enhanced low temperature properties have shown faster start-up flow and in some cases, more rapid shift times. Hydraulic fluids with improved cold flow performance allow more rapid equipment warm-up and faster response at low temperatures.

The means for ease of alignment maintenance of tandem axles on conventional tractor/trailers has been a requirement largely overlooked or not recognized by common carrier fleet operators and the equipment manufacturers in United States. A review of developments of the past 10 years will provide a more perspective understanding of current maintenance practices and why there is a need for change. Some complacency has existed within the industry and a greater understanding of the ramifications of misaligned trailer axles is needed. Improved maintenance procedures for better control of trailer axle alignment will reduce operating expenses and, from a standpoint of highway safety, will also reduce the potential for accidents.

Air brake adjustment is a critical factor in achieving optimum system performance. Brake chamber stroke must be minimized if maximum brake torque is to be achieved. A significant loss of brake torque occurs over what is considered to be the acceptable brake adjustment range particularly if the brake is hot. A large number of air braked vehicles on the road have brakes out of adjustment or have brakes considered to be in adjustment that are operating at a reduced effectiveness level. Better adjustment maintenance would improve truck safety.

Recent experimental work involving surfaces is described, and it is shown that by measuring the distributions of asperities, it is possible to evaluate the nature and size of contact for various surface loads. The removal of adsorbed gas layers from the surfaces of crystals is shown to affect the friction markedly, while the “ploughing” term in the frictional cooefficient emerges as the important factor in explaining the anisotopy of friction found on some crystalline solids. The effect of microdefects on the strength of glasses and their removal by etching is described. The behavior of glasses is compared with that of hard polymers such as lucite. Finally, the property a surface has as a “free boundary” in stress wave propagation is considered, with particular reference to the fracture behavior of brittle solids in plate form.

The University of Washington EcoCAR2 team (UWEC2) is currently in the process of building a Plug-in Hybrid Electric Vehicle (PHEV) for the EcoCAR2 Challenge. This competition challenges 15 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. In order to be competitive in EcoCAR2, grid electricity is relied on heavily and the use of the Utility Factor method presented in SAE J2841 - Utility Factor Definitions must be used to compare emissions and consumption results with traditional vehicle results. Powertrain simulation in Autonomie was performed to explore many different hybrid architectures. The simulation results were normalized using the Utility Factor method to reach final architecture and component decisions.

Traditional electrode materials for lithium-ion storage cells are typically crystalline layered structures such as metal oxides, and graphitic carbons. These materials power billions of portable electronic devices in today's society. However, large-scale, high-capacity storage devices capable of powering hybrid electric vehicles (HEV″s) or their plug-in versions (PHEV's) have much more demanding requirements with respect to safety, cost, and the power they must deliver. Recently, nanostructured solid state materials, which are comprised of two more compositional or structural phases, have been found to show exciting possibilities to meet these criteria.