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Pass-by/exterior noise of earth moving machines (EMM) and forestry machines is becoming a focus at early product development stages. ISO 6395 (2) or EC/2000/14 (1) standards defines exterior noise test procedure for EMM. However, these standards do not provide insights for diagnosing any noise issues which may arise. The analysis challenges are posed by the moving machine and acoustic sources with respect to the stationary hemisphere target microphone on the ground and changing operating condition of sources as function of time. There is need to develop a seamless methodology to identify acoustic sources, quantify respective source strengths and rank partial contributions from each source to the total target microphone response in order to overcome the aforementioned challenges.

To improve overall customer experience, it is imperative to minimize the noise levels inside agricultural equipment cab. Up-front prediction of acoustic performance in product development is critical to implement the noise control strategies optimally. This paper discusses the methodology used for virtual modeling of a cab on agricultural equipment for prediction of interior noise. The Statistical Energy Analysis (SEA) approach is suitable to predict high frequency interior noise and sound quality parameters such as articulation index and loudness. The cab SEA model is developed using a commercial software. The structural and acoustic excitations are measured through physical testing in various operating conditions. The interior noise levels predicted by the virtual model are compared with the operator ear noise levels measured in the test unit. The resultant SPL spectrum from SEA correlates well with the test.

The demands on improving the noise, vibration and harshness of the golf mowing machines are growing rapidly. Low frequency vibrations at the human touchpoints are one of the important factors leading to the discomfort of operators on these machines. In the present work, low frequency vibrations experienced by the operator of the golf mowing machine are reduced using finite element analysis (FEA) and validated by a physical test. Initially, testing observed high vibration at the command arm, where some of the operating controls are placed. FEA was carried out on a frame level assembly and the design was iterated to affect these vibration levels. The golf mowing machine considered in this work is powered by a gasoline engine, which is the source of excitation in the current scenario. The operational forces of the engine were measured by using blocked-force transfer path analysis at its mounts. The modal frequency response analysis used these calculated forces as an input excitation.

An experimental study is performed to investigate the effects of charge motion control on in-cylinder fuel-air mixture preparation and combustion inside a direct-injection spark-ignition engine with optical access to the cylinder. High-pressure production injector is used with fuel pressures of 5 and 10 MPa. Three different geometries of charge motion control (CMC) device are considered; two are expected to enhance the swirl motion inside the engine cylinder whereas the third one is expected to enhance the tumble motion. Experiments are performed at 1500 rpm engine speed with the variation in fuel injection timing, fuel pressure and the number of injections. It is found that swirl-type CMC devices significantly enhance the fuel-air mixing inside the engine cylinder with slower spray tip penetration than that of the baseline case without CMC device. Combustion images show that the flame growth is faster with CMC device compared to the similar case without CMC device.

A separator is a membrane that prevents the physical contact between the positive and negative electrodes while enabling ionic transport. The integrity of the separator is vital to the performance and reliability of a battery. This paper presents finite element stress analysis for the separator in a lithium-ion battery using a macro-scale battery cell model. In this model, the porous electrodes were treated as homogenized media and represented with the effective properties estimated using the rule of mixtures. To compute the deformation due to lithium (Li) intercalation & deintercalation and temperature variation, the Li concentration distribution and temperature change due to electrochemical reactions must be known. These parameters were computed using a multi-physics model in COMSOL and mapped to the macro-scale model in ANSYS. Numerical simulations were conducted to identify the locations and magnitudes of the maximum strain and stress of the separator in the pouch cell.

Light-weight 3-D models offer improved communication and visualization for advertising, marketing, service technicians, suppliers and other business partners. These models also may be a ready source of geometry and a window into a company's intellectual property for miscreants seeking to pirate designs and to produce counterfeit or will-fit parts. What approaches and tools are available to help protect a company's intellectual property while enabling it and its business partners to benefit from widespread distribution of 3-D animations and models? How should they be applied to effectively protect intellectual property? This paper provides a general survey of techniques available for protecting intellectual property in 3-D models when sending these files outside of a company and into broad distribution.

Ethanol and other high heat of vaporization (HoV) fuels result in substantial cooling of the fresh charge, especially in direct injection (DI) engines. The effect of charge cooling combined with the inherent high chemical octane of ethanol make it a very knock resistant fuel. Currently, the knock resistance of a fuel is characterized by the Research Octane Number (RON) and the Motor Octane Number (MON). However, the RON and MON tests use carburetion for fuel metering and thus likely do not replicate the effect of charge cooling for DI engines. The operating conditions of the RON and MON tests also do not replicate the very retarded combustion phasing encountered with modern boosted DI engines operating at low-speed high-load. In this study, the knock resistance of a matrix of ethanol-gasoline blends was determined in a state-of-the-art single cylinder engine equipped with three separate fuel systems: upstream, pre-vaporized fuel injection (UFI); port fuel injection (PFI); and DI.

A numerical modeling and design methodology for wear occurring in bodies that experience oscillatory contact is proposed. The methodology builds upon a widely used iterative wear prediction procedure. Two techniques are incorporated into the methodology to minimize the simulation computational costs. In the first technique, an extrapolation scheme that optimizes the use of resources while maintaining simulation stability is implemented. The second technique involves the parallel implementation of the wear prediction methodology. The methodology is used to predict the wear on an oscillatory pin joint and the predicted results are validated against those from actual experiments.

All modern automotive automatic transmissions require the use of a torque converter to allow for the transmission of torque from the engine to the drivetrain. Although they are commonly used throughout the automotive industry, there is little understanding of the internal flows within the torque converter. An experimental study has been conducted to reveal the internal flow characteristics within a production torque converter using Laser Doppler Velocimetry (LDV) under the operating conditions. LDV measurements were conducted on the planes between impeller blades, and the gap between the impeller and turbine blades. The study showed that the internal flow is highly complex and the difference in rotor speeds between the impeller and turbine compound the flow effects. Transmission oil flows in the planes at the impeller exit and gap region were affected by the turbine blade as it passed.

Many engineering systems create unwanted noise that can be reduced by the careful application of engineering noise controls. When this noise travels down tubes and pipes, a tuned resonator can be used to muffle noise escaping from the tube. The classical examples are automobile exhaust and ventilation system noise. In these cases where a narrow frequency band of noise exists, a traditional engineering control consists of adding a tuned Helmholtz resonator to reduce unwanted tonal noise by reflecting it back to the source (Temkin, 1981). As long as the frequency of the unwanted noise falls within the tuned resonator frequency range, the device is effective. However, if the frequency of the unwanted sound changes to a frequency that does not match the tuned resonator frequency, the device is no longer effective. Conventional resonators have fixed tuning and cannot effectively muffle tonal noise with time-varying frequency.

A transformation of agriculture reached commercial reality at the beginning of this century as automated steering of agricultural machine systems increased the productivity and convenience in crop production systems. Following guidance, additional technologies have resulted in increasing optimized machine productivity. Today, integrated worksite solutions through machine and information management continues to transform agriculture. This is the precursor to autonomous worksite solutions that lead to the optimization of the worksite ecosystem. This paper will review the progress from the perspective of the customer value provided by increasing automated systems and the industry execution of autonomous driving technologies and will enable the pathways to autonomous worksites.

This work presents a method for simultaneously capturing visible and infrared images along with pressure data in an optical Diesel engine based on the International 4.5L VT275 engine. This paper seeks to illustrate the merits of each imaging technique for visualizing both in-cylinder fuel spray and combustion. The engine was operated under a part load, high simulated exhaust gas recirculation operating condition. Experiments examining fuel spray were conducted in nitrogen. Overlays of simultaneously acquired infrared and visible images are presented to illustrate the differences in imaging between the two techniques. It is seen that the infrared images spatially describe the fuel spray, especially fuel vapors, and the fuel mixing process better than the high-speed visible images.

Diesel injection equipment is required to be more accurate and higher in pressure to meet the increasingly strict emission, fuel consumption regulations and higher engine performance. It also needs to achieve a number of requirements such as robustness against diversified market fuels, easy installation to engine, etc.

New models are being developed to represent the geometry and movements of people in seated postures. The positions and motions of the torso skeletal structures for different amounts of lumbar curvature have been studied and represented in side view, two dimensional computer models of the average man, small woman, and large man. Some further developments for the average man include: 1. two dimensional, articulated drafting template, 2. three dimensional computer model of the skeletal system with soft tissue thicknesses added to represent the external body contours on the back of the torso, and 3. model of forces and moments between body segments based on seated posture, body segment masses, and seat surface forces. This paper describes these new biomechanical models and their potential uses in designing seats that more comfortably fit and move with people.

As environmental regulations become more stringent, manufacturers are confronted with the task of product-design considering environmental impacts. Life Cycle Analysis (LCA) is a developing technique that attacks this problem. LCAs provide environmental information for decision making by consumers, manufacturers, and governments. These decisions significantly affect the ability to maximize source reduction, re-use, recyclability, and recycled content. LCAs can aid in diminishing the negative impact a product has on the environment and can be utilized as a partial solution of our nations' (worlds') growing waste management problem. To date, the application of LCAs has varied from product comparison to process development and improvement. The results from these analyses have differed because of differing assumptions and differing choices of boundary conditions. An appropriate Life Cycle Analysis should be consistent across products, locations, and especially across experimenters.

Statistical Energy Analysis (SEA) is a useful tool for predicting the transmission of noise and vibration through the structures of automotive vehicles. This work discusses the identification of SEA internal loss factor parameters from experimental measurements of vehicle sound pressure levels and structural accelerations. A simple automotive vehicle SEA model can be constructed from elements idealized as uniform beams, flat plates and acoustic volumes. Such an SEA automotive vehicle model can accurately predict the vibro-acoustic response of an automotive vehicles when appropriate equivalent SEA parameters are identified from in situ experimental data. This paper will present an algorithm for identifying internal loss factors for SEA models. The paper will include an example of the application of the algorithm to identification of automotive vehicle internal loss factors from measured vehicle response data.

Design of a hybrid electric vehicle chassis for the 1993 and 1994 HEV Challenge is presented. Computer finite element modeling and solid modeling techniques were used in developing the chassis. The main design parameters are presented and described. Final chassis design was tested, using finite element analysis, to ensure overall structural integrity and occupant safety. The chassis proved to be safe and reliable, under the rigors of competition driving, in the 1993 and 1994 HEV Challenges.

Lower extremity (knee) trauma is currently based on a bone fracture criterion derived from impacts of aged specimens. Recent clinical studies, however, indicate that a chronic disease (post-traumatic osteoarthritis), may be precipitated after mechanical insult without obvious bone fracture(1). It is hypothesized this is due to microcracking of subchondral bone under cartilage. This hard tissue layer is known to change with age and pathology. Ten ‘aged’ (71 years) and ten ‘young’ (47 years) cadaver knee joints were impacted to study the influence of age and pathology on the fracture load, and incidents of occult injury. Our results indicate that fracture load, per se, was independent of specimen age. On the other hand, severely pathological specimens required significantly higher loads to fracture bone. Occult microcraking was also observed in subfracture experiments, however, fewer incidents were recorded for the ‘aged’ specimens.

The location of the pelvis in the seated automobile operator is critical for proper packaging and seat comfort design. The pelvis is the skeletal structure which contains the hip joint (H-point) and ischial tuberosity (D-point). The orientation of the pelvis largely determines the curvature in the low back which is supported by lumbar supports in the seat back. A methodology has been developed that uses onboard video and pressure measurement systems to locate the pelvis. This system has been used in a mid-sized vehicle on seated operators driving the vehicle on the highway. This paper describes the methodology and the location of the pelvis in seated automobile operators.

Five small two-stroke engine designs were tested at different air/fuel ratios, under steady state and transient cycles. The effects of combustion chamber design, carburetor design, lean burning, and fuel composition on performance, hydrocarbon and carbon monoxide emissions were studied. All tested engines had been designed to run richer than stoichiometric in order to obtain satisfactory cooling and higher power. While hydrocarbon and carbon monoxide emissions could be greatly reduced with lean burning, engine durability would be worsened. However, it was shown that the use of a catalytic converter with acceptably lean combustion was an effective method of reducing emissions. Replacing carburetion with in-cylinder fuel injection in one of the engines resulted in a significant reduction of hydrocarbon and carbon monoxide emissions.