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Original equipment manufacturers and their customers are demanding more efficient, lighter, smaller, safer, and smarter systems across the entire product line. In the realm of automotive, agricultural, construction, and earth-moving equipment industries, an additional highly desired feature that has been steadily trending is the capability to offer remote and autonomous operation. With the previous requirements in mind, the authors have proposed and validated a new electrohydraulic steering technology that offers energy efficiency improvement, increased productivity, enhanced safety, and adaptability to operating conditions. In this paper, the authors investigate the new steering technology's capacity to support remote operation and demonstrate it on a compact wheel loader, which can be remotely controlled without an operator present behind the steering wheel. This result establishes the new steer-by-wire technology's capability to enable full autonomous operation as well.

NO and soot emissions from Diesel engines are dependent on several parameters related to the engine design and operating conditions. Multidimensional models are increasingly employed to study the effect of these parameters. In this paper, a multidimensional model for flows, sprays and combustion in engines is employed to study the dependence of NO and soot formation and oxidation on injection timing, injection pressure, chamber temperature, EGR and ignition delay, and compare the computed trends with those observed in experimental studies reported in the literature. Computations are carried out in a typical heavy-duty Diesel engine and additional computations in a constant volume chamber are used to clarify the engine results when appropriate. For several parametric changes, the experimentally observed trends are reproduced. However, several limitations are identified. The structure of the computed combusting jet has differences with those suggested from recent experiments.

The renewed interest in electric and hybrid-electric vehicles has been prompted by the drastic rise in oil prices in 2008 and launch of new initiatives by the Federal Government. One of the key issues is to promote the incorporation of electric drivetrain in vehicles at all levels and particularly with emphasis on educational activities to prepare the workforce needed for the near future. Purdue University has been conducting a Grand Prix for over 50 years with Gas-powered Karts. In April 2010, an annual event was initiated to hold an EV Grand Prix where 17 EV Karts participated in the competition. Four of the participating teams comprised of Purdue students in a new graduate course for EV design and fabrication. Using the basic framework of the gas-powered Kart, an electric version was developed as a part of this course. Other participants were also provided with the guidelines and design parameters developed for the course and competition.

The range of applications of heavy duty diesel engines is quite diverse. The development of diesel engines has been characterized by a steady increase in power to weight ratios, with the turbocharger being the key component in achieving this increased performance. The turbocharger, consisting of a radial or axial flow turbine and a radial flow compressor, presents perhaps one of the most challenging tasks facing the turbomachinery designer. This is, to a p a t extent, due to the highly unsteady environment in which the turbocharger operates. The time scales of this unsteadiness range fiom those on the order of exhaust valve frequency to those associated with transient operation during acceleration and deceleration. In order to predict the time-accurate performance of the turbocharger in this environment, a range of dynamic models can be envisioned spanning the range from quasi-steady assumptions to full viscous flow solvers.

The feasibility of controlling the threshing cylinder of a conventional corn combine with electro hydraulic elements controlled by a digital computer was concluded. The laboratory experiments attained the performance index established after consultation with manufacturers and farmers

Farmers are a small group, mostly college educated who run multi-million dollar yearly operations. Recent favorable economics has allowed this sector to look at new technology and determine the best way to invest in it. New considerations in the last few years have led to minimum/alternative tillage and planting, site specific farming decisions and small technology groups of farmers. The authors have put together their thoughts and wants which should be evaluated by future suppliers of technology and farm machinery.

Detailed heat transfer measurements were made in the combustion chamber of a Cummins single cylinder NH-engine in two configurations: cooled metal and ceramic-coated. The first configuration served as the baseline for a study of the effects of insulation and wall temperature on heat transfer. The second configuration had several in-cylinder components coated with 1.25 mm (0.050″) layer of zirconia plasma spray -- in particular, piston top, head firedeck and valves. The engine was operated over a matrix of operating points at four engine speeds and several load levels at each speed. The heat flux was measured by thin film thermocouple probes. The data showed that increasing the wall temperature by insulation reduced the heat flux. This reduction was seen both in the peak heat flux value as well as in the time-averaged heat flux. These trends were seen at all of the engine operating conditions.

This research provides a capacitance based method for monitoring the integrity of tires and other polymeric products during manufacturing and throughout the useful product life. Tire and wheel failures and tire degradation were the reported cause for approximately 19320 vehicle crashes over a two and a half year period according to the U.S. Department of Transportation National Highway Traffic Safety Administration's 2008 survey. Tires are complex composite structures composed of layers of formulated cross-linked rubber, textiles, and steel reinforcement layers. Tire production requires precise manufacturing through chemical and mechanical methods to achieve secure attachment of all layers. Tires are subjected to a variety of harsh environments, experience heavy loads, intense wear, heat, and in many cases lack of maintenance. These conditions make tires extremely susceptible to damage.

A noise source identification technique for the analysis of thermal systems is presented. The proposed method uses transient spectral sound data to assist in determining the source of sound radiation by tracking the variation of the frequency of tones during transient thermal loading (i.e., thermal system warm-up). By considering the temperature dependence of the modulus of elasticity (Young's modulus) it can be shown that structure related tones will decrease in frequency during warm-up. Tones due to propagation of sound in many fluids (i.e., gases and water) will increase in frequency during warm-up due to the temperature dependence of the speed of sound. The analysis method is demonstrated by identifying the source of several noise tones for a pulse combustion furnace.

Increased power and fuel efficiency requirements ofmodern vehicle diesel engines have lead to wide pread use of turbocharging to increase engine power-to-weight ratio. Typically, these systems employ pulse-turbocharging where an increase in exhaust gas transport efficiency is achieved at the expense of creating a highly unsteady flow through the turbine. This imposed unsteadiness is known to have a significant effect on turbine performance. To date, research performed to quantify the effects of exhaust pulsations on the performance of radial turbocharger turbines has been performed in off-engine facilities which simulate the engine manifold conditions. However, to better gauge the applicability of these data, a detailed investigation into the actual on-engine turbocharger operating environment is required. Research at Purdue University is focused on the characterization of the nature of the on-engine turbine operating environment and how it relates to turbocharger performance.

Multidimensional numerical simulations are performed to predict and optimize engine performance of a spark-ignited natural gas engine. The effects of swirl and combustion chamber geometry on in-cylinder turbulence intensity, burning rate and heat transfer are investigated using the KIVA multidimensional engine simulation computer code. The original combustion model in the KIVA code has been replaced by a model which was recently developed to predict natural gas turbulent combustion under engine-like conditions. Measurements from a constant volume combustion chamber and engine test data have been used to calibrate the combustion model. With the numerical results from KIVA code engine thermal efficiencies were predicted by the thermodynamics based WAVE code. The numerical results suggest alternative combustion chamber designs and an optimum swirl range for increasing engine thermal efficiency.

Modern diesel engines typically utilize pulse-turbocharging where an increase in exhaust gas transport efficiency is achieved at the expense of creating a highly unsteady flow through the turbine which may have a detrimental effect on turbine performance. As the turbocharger plays a major role in the performance and emissions of the engine system, the characterization of on-engine turbocharger aerodynamics is critical. Thus, this paper is directed at the investigation of the turbocharger turbine volute inlet flowfield on an in-line, six cylinder, diesel engine. Specifically, Particle Image Velocimetry (PIV), a quantitative non-intrusive whole flowfield measurement technique, is used to perform a detailed study of the on-engine pulsating flowfield at the volute inlet of the twin-entry turbocharger turbine.

The identification of the propulsion noise of turbofan engines plays an important role in the design of low-noise aircraft. The noise generation mechanisms of a typical turbofan engine are very complicated and it is not practical, if not impossible, to identify these noise sources efficiently and accurately using numerical or experimental techniques alone. In addition, a major practical concern for the measurement of acoustic pressure inside the duct of a turbofan is the placement of microphones and their supporting frames which will change the flow conditions under normal operational conditions. The measurement of acoustic pressures on the surface of the duct using surface-mounted microphones eliminates this undesirable effect. In this paper, a generalized acoustical holography (GAH) method that is capable of estimating aeroacoustic sources using surface sound pressure is developed.

Acoustic array techniques are presented as alternatives to intensity measurements for source identification in automotive and industrial environments. With an understanding of the advantages and limitations described here for each of the available methods, a technique which is best suited to the application at hand may be selected. The basic theory of array procedures for Nearfield Acoustical Holography, temporal array techniques, and an Inverse Frequency Response Function technique is given. Implementation for various applications is discussed. Experimental evaluation is provided for tire noise identification.

The turbocharger, consisting of a radial or axial flow turbine and an radial flow compressor presents perhaps one of the most challenging tasks to the turbomachinery designer. Due to the necessity of speed changes in the diesel engine, the turbocharger transits a wide variety of operating points in its normal operation. During an engine speed acceleration or deceleration there will be a lag in the required air delivery to the engine, resulting in increased smoke emission and limiting the power delivered by the engine. In order to investigate the dynamic performance of a turbocharged engine, an essential first step must be the development of an adequate model for transient characteristics of the turbocharger. One of the significant problems that must be overcome for the modeling effort to be successful is a detailed experimental description of the transient performance of the device.

In recent years, Nearfield Acoustical Holography (NAH) has been used to identify stationary vehicle exterior noise sources. However that application has usually been limited to individual components. Since powertrain noise sources are hidden within the engine compartment, it is difficult to use NAH to identify those sources and the associated partial field that combine to create the complete exterior noise field of a motor vehicle. Integrated Nearfield Acoustical Holography (INAH) has been developed to address these concerns: it is described here. The procedure entails sensing the sources inside the engine compartment by using an array of reference microphones, and then calculating the associated partial radiation fields by using NAH. In the second part of this paper, the use of farfield arrays is considered. Several array techniques have previously been applied to identify noise sources on moving vehicles.