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Improving the aerodynamic drag level of semi-trailers will contribute largely to reduce the fuel consumption and the emissions of harmful gases of heavy duty vehicles. The final step in product validation of aerodynamic drag reduction devices is often conducting fuel savings test during operational activities. During an operational test, data is gathered for a period when the vehicle is not equipped with an aerodynamic device and consequently for a period with the device equipped. A simple fuel consumption comparison between the periods does not give the desired accurate result as the operating conditions are different for the control and test period. In an attempt to take these varying conditions into account, the average fuel consumption per ride is modeled as a linear function of several independent variables: the wind conditions, the outside temperature, the humidity, the payload, the road inclination and the presence of the drag reduction device.

According to research studies, epidemics such as SARS, COVID-19 spread have caused huge negative impacts on population, health and the economy around the globe. The outbreak places a huge burden on international health systems that were already straining to address AIDS, tuberculosis, malaria, and a host of other conditions. Research has proven that incase infected person is not traced timely then the spread of infection in society will take the shape of large-scale community transmission. Most of the infections spread because they got unnoticed by the infected person. One part of the access checker scans is a person’s body temperature by measuring infrared radiation emitted by their skin. Fever screening by infrared thermal imaging has become more widespread following the SARS infection, and particularly during the pandemic H1N1 and COVID-19 outbreak. Skin temperature is measured without contact by monitoring the emitted infrared radiation.

As the FTP-75 drive cycle does not have a prescribed gear shift pattern, automotive OEMs have the flexibility to design. Conventionally, gear shift pattern was formulated based on trial and error method, typically with 10 to 12 iterations on chassis dynamometer. It was a time consuming (i.e. ~ 3 to 4 months) and expensive process. This approach led to declaring poor fuel economy (FE). A simulation procedure was required to generate a gear shift pattern that gives optimal trade-off amongst conflicting objectives (FE, performance and emissions). As a result, a simulation tool was developed in MATLAB to generate an optimum gear shift pattern. Three different SUV/UV models were used as test vehicles in this study. Chassis dyno testing was conducted, and data was collected using the base and optimized gear shift patterns. Dyno test results with optimized gear shift pattern showed FE improvement of ~ 4 to 5% while retaining the NOx margin well above engineering targets.

The winter of 2013-2014 provided an opportunity to operate off-road vehicles in cold weather for extended time as part of a vehicle/tier 4 diesel engine validation program. An unexpected area of study was the performance of high efficiency, on engine, fuel filters during continuous vehicle operation in cold weather. During the program we observed unexpected premature fuel filter plugging as indicated by an increase in pressure drop across the filter while in service. Field and laboratory testing was completed at John Deere and Donaldson to understand the cause of filter plugging. Although conditions were found where winter fuel additives could cause plugging of high efficiency filters, premature filter plugging occurred even when testing with #1 diesel fuel. This fuel contained no additives and was used at temperatures well above its cloud point.

This SAE Recommended Practice establishes uniform test procedures and performance requirements for engine-off heating, ventilation, and air conditioning (HVAC) systems in order to achieve driver thermal comfort in both winter and summer rest periods. This specification will apply to heavy trucks with and without sleeper compartments, including but is not limited to Class 6, 7, and 8 powered vehicles.

This SAE test method establishes a uniform test procedure for determining the gravimetric (mass based) efficiency and pressure drop performance levels of operator enclosure panel type filters on off-road, self-propelled work machines used in earth moving, and forestry, as defined in SAE J1116 and for agricultural equipment as defined in ANSI/ASAE S390, and equipped with an operator enclosure with a powered fresh air system. ISO/TS 11155-1 may additionally be used, which describes the use of particle sizing devices to measure the fractional (particle size) efficiency of panel type filters for automotive cabin filter applications. Automotive cabin filters are similar to filters described in this procedure, and the ISO/TS 11155-1 test method is therefore directly applicable.

This SAE Recommended Practice establishes a uniform test procedure for determining performance levels of operator enclosure panel type air filters on off-road, self-propelled work machines used in construction, general-purpose industrial, agriculture, and forestry as defined in SAE J1116 and equipped with an operator enclosure with a powered fresh air system.

This SAE Recommended Practice was developed by SAE, and the section “Standard Classification and Specification for Service Greases” cooperatively with ASTM, and NLGI. It is intended to assist those concerned with the design of heavy duty vehicle components, and with the selection and marketing of greases for the lubrication of certain of those components on heavy duty vehicles like trucks and buses. The information contained herein will be helpful in understanding the terms related to properties, designations, and service applications of heavy duty vehicle greases.

This document lists common terminology for vacuum excavation and sewer cleaning equipment, including component names and specific work completed by these machines. This document also illustrates some common types of equipment.

This paper presents the development of a fluid quality sensor to provide a real-time, on-board oil quality assessment capability for commercial, military, and off-highway vehicle applications. The sensor provides for improved vehicle health state awareness and enables a condition-based approach to lubricant maintenance. The technology is based on a broadband approach to electrochemical impedance spectroscopy (EIS) and is applicable to all high impedance fluids. The EIS results are fused with the measurements from a capacitive relative humidity sensing element and are normalized with respect to temperature as measured by an embedded thermistor. The authors' experiences in developing, packaging, and testing this technology are chronicled.

The effect of cavitation plays a fundamental role in the hydraulic components design and the capability of predicting its causes and characteristics is fundamental for the optimization of fluid systems. In this paper, a multidimensional CFD approach is used to analyze the cavitating phenomena typical of hydraulic components using water as operating fluid. An open source fluid-dynamics code is used and the original cavitation model (based on a barotropic equation of state and homogeneous equilibrium assumption) is extended in order to account also for gases dissolved in the liquid medium. The effect of air dissolution into liquid water is modeled by introducing the Henry law for the equilibrium condition, and the time dependence of solubility is calculated on a Bunsen Coefficient basis. Furthermore, a simplified approach to turbulence modeling for compressible flows is coupled to the cavitation model and implemented into the CFD code.

The paper contains experimental results of soil stress state under loading of commercial wheeled vehicles. The measurements were performed with the use of SSTs (Stress State Transducers), which enable to determine soil pressures needed for calculations of stress state at a point: principal stresses and their direction cosines as well as octahedral stresses. A detailed description of the measuring method with an introductory theory of operation of the SST together with some methodology aspects of soil pressure measurements are included. The field tests were conducted on three different soil surfaces: loess, sand and turf as well as on snow surface in winter conditions. For the tests, two vehicles were used: a 5,6T 4x4 truck and a 14T 6x6 truck. The vehicles were driven at constant low speed or at different speeds. Moreover, effects of wheel loading, reduced inflation pressure, drive modes (rolling or driving) were also analyzed.

In the last few years, some of the computational limitations imposed by the classical Boundary Element Methods (BEM) have been overtaken thanks to the Fast Multipole BEM (FMBEM) which allows solving large acoustic models much faster. Nevertheless, as the BEM, the FMBEM suffers from non-uniqueness of the solution and the exterior prediction is polluted by fictitious resonances. Since the FMBEM is based on an iterative solver, not only the accuracy is degraded. In fact, the number of iterations to the convergence, in correspondence of a fictitious resonance, is larger and the total computational time increases. Applying the impedance condition over the whole inner boundary allows to completely damp fictitious resonances with a drastic increase of computational cost. Nevertheless, when the condition is applied on a well-chosen percentage of elements, the accurate solution is obtained even faster.

Mechanical and thermal properties of the rubber compounds of a tire play an important role in the overall performance of the tire when it is in contact with the terrain. Although there are many studies conducted on the properties of the rubber compounds of the tire to improve some of the tire characteristics, such as the wear of the tread, there are a limited number of studies that focused on the performance of the tire when it is in contact with ice. This study is a part of a more comprehensive project looking into the tire-ice performance and modeling. In this study, to understand the effect of different rubber compounds on the tire performance, three identical tires from the same company have been chosen. The tires’ only difference is the material properties of the rubber. Two approaches have been implemented in this study.

New communication and information processing technology is significantly changing the world of logistics and transportation. A new program established by the U.S. Department of Transportation, known as the Intelligent Vehicle-Highway System (IVHS) Program, seeks to apply this technology to transportation in an organized fashion. The goal is to improve the efficiency and safety of the highway system. Many of the new technologies have the potential to allow the automation of the hazard communication process during hazardous material transportaiton. This paper identifies and discusses some of the potential applications of IVHS technology to the hazardous material transportation environment.

Presenting a brand new approach to heat exchangers for engines, transmissions, hydraulic systems, etc. This new heat exchanger is made of only two pieces of circular extruded aluminum profiles: Core and shell. No soldering: The core and the shell is assembled by a minimum of automated work. In an oil to water cooling application, the active surface on the oil side of the core is enlarged by fins 0.2 mm thick, 0.3 mm spacing, and 3 mm high. The fins are made in unique production machines and enlarge the active surface area approximately five times compared to a conventional heat exchanger of the same dimensions. The principle utilizes the low pressure drop at laminar flow and avoids the disadvantage of low heat transfer after a certain laminar flow length. The result is approximately three times higher oil heat dissipation, combined with very low oil pressure drop, compared to conventional technique.

Modern agricultural machines are very complex, requiring extensive monitoring of multiple operations at the same time as they travel over very rough terrain. Hence, the cabs must be designed to provide not only good visibility of all monitors and easy access to all controls, but operator comfort and safety as well. This includes climate control (temperature, humidity, dust, noise, etc.), vibration damping, easy access on to and off of the tractor, good visibility from the cab and no controls jutting out where they could constitute a hazard. Good cab design promotes efficiency, comfort and safety.

Cereal grains are subjected to physical forces produced by agricultural machinery during and after harvest. The resulting physical damages have biological consequences such as reduced germination and yield. Damages may be minimized by adjusting equipment to take into account the physical resistance of grain to mechanical and dynamic loading. This paper describes methods for evaluating grain-to-ear binding force and grain physical resistance and presents the results for barley, rye, spring wheat and winter wheat varieties. Results of research on relationships between physical forces and biological effects on varieties of spring wheat and winter wheat are also presented and discussed.

A machine vision system was developed to identify and locate harvestable spears of asparagus. An image acquisition vehicle was fabricated to videotape portions of asparagus rows from a commercial production field. Images were acquired using a monochrome CCD camera. The detection of reflectance properties of asparagus was enhanced by using optical bandpass filters for near-infrared radiation. Videotaped segments acquired in the field were analyzed. Image processing techniques based on geometrical characteristics of asparagus spears were used to identify and locate harvestable spears in the images. Harvestable spears measured in the field were compared to those found by machine vision. The vision system correctly identified from 86 to 97% of the harvestable spears in six 15 m row segments analyzed. The uncertainty in the location of spears was within a 2.97 by 5.39 cm window with 95% confidence.

As part of a study commissioned by Transport Quebec aimed at evaluating the impact of commercial vehicles on the safety of railway crossings, the acceleration performances of various heavy vehicles (buses, straight trucks and tractor-trailer combinations) was measured. The goal of these tests was to identify the typical worst acceleration performances of classes of commercial vehicles used in the calculations of sight triangles at railway crossings. A total of 21 commercial vehicles were subjected to testing on test track facilities and on nine railway crossings representing typical configurations found in North-America. Results were used to develop a heavy vehicle acceleration mathematical model according to the vehicles' technical specifications. The acceleration performances were then combined with various criteria associated with driver perception-reaction times, and also driver performance and skill during gear shifting.