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This paper outlines the techniques used to install both a full scale and a half scale tractor-trailer model in the 9×9 meter National Research Council of Canada wind tunnel in Ottawa, Canada. The objectives were to measure the cooling drag of an active cooling system and to investigate the aerodynamic testing limits of long, yawed models inside a solid wall wind tunnel. The tunnel interference problem is discussed as it pertains to the upstream boundary, test section floor, downstream boundary, ceiling and side walls and tractor-trailer surface pressure measurements. A potential solution to the problem, however, is the subject of a follow-up paper.

During the past decades the public acceptance of the actual environmental legislation has gradually turned into an active support of the same. Test methods have anyhow become more cost heavy and time consuming, underlining the need of simplified tests with reasonable correlation to the legal methods. Generally, the emissions under static and semistatic load conditions are gradually eliminated, why the heavy pollution now comes from transient periods of the driving pattern. Consequently a transient test procedure must satisfy the quality requirements on a short test applicable to vehicles from cars to heavy trucks and busses. The INertia COLLection system described here is developed to enable low cost and well repeatable measurements of the emission characteristics of engine systems in light and heavy vehicles under transient load. The system is easy to adopt and does not need any chassis dynamometer.

Abstract This article proposes a novel approach of a hybrid system of physics and data-driven modeling for accurately estimating the state of charge (SOC) of a battery. State of Charge (SOC) is a measure of the remaining battery capacity and plays a significant role in various vehicle applications like charger control and driving range predictions. Hence the accuracy of the SOC is a major area of interest in the automotive sector. The method proposed in this work takes the state-of-the-art practice of Kalman filter (KF) and merges it with intelligent capabilities of machine learning using neural networks (NNs). The proposed hybrid system comprises a physics-based battery model and a plurality of NNs eliminating the need for the conventional KF while retaining its features of the predictor-corrector mechanism of the variables to reduce the errors in estimation.

Biofuel can enable a sustainable transport solution and lower greenhouse gas emissions compared to standard fuels. This study focuses on biodiesel, implemented in the easiest way as drop in fuel. When mixing biodiesel into diesel one can run into problems with solubility causing contaminants precipitating out as insolubilities. These insolubilities, also called soft particles, can cause problems such as internal injector deposits and nozzle fouling. One way to overcome the problem of soft particles is by filtration. It is thus of great interest to be able to quantify fuel filters’ ability to intercept soft particles. The aim of this study is to test different fuel filters for heavy-duty engines and their ability to filter out synthetic soft particles. A custom-built fuel filter rig is presented, together with some of its general design requirements. For evaluation of the efficiency of the filters, fuel samples were taken before and after the filters.

Abstract The 2010 Environmental Protection Agency (EPA) Emission Standard for heavy-duty engines required 0.2 g/bhp-hr over certification cycles (cold and hot Federal Test Procedure [FTP]), and the California Air Resources Board (CARB) standards require 0.02 g/bhp-hr for the same cycles leading to a 90% reduction of overall oxides of nitrogen (NOx) emissions. Similar reductions may be considered by the EPA through its Cleaner Trucks Initiative program. In this article, aftertreatment system components consisting of a diesel oxidation catalyst (DOC); a selective catalytic reduction (SCR) catalyst on a diesel particulate filter (DPF), or SCR-F; a second DOC (DOC2); and a SCR along with two urea injectors have been analyzed, which could be part of an aftertreatment system that can achieve the 0.02 g/bhp-hr standard.

The commercial vehicle industry is evolving faster with the rise in multifarious aspects deciding a company's progress. In the current scenario, vehicle performance and its reliability in the areas of payload, fuel economy, etc. play vital roles in determining its sustenance in the industry, in addition to reducing driver fatigue and improving comfort levels. Test quality and time is the key to assure and affirm, smooth and quick launch of the product into the market. This paper details on the design of Multi-Axis road data simulator which entails realistic loads onto the components for capturing meaningful information on behavior of the product and recreate the field failure modes. The design was conceptualized keeping in mind both cost (for initial installation and running cost) and time for testing without loss in the convergence factor.

Measurements of soot and SOF emitting from automobile engines by conventional gravimetric method and soxhlet extraction method are difficult and time-consuming processes. The composition in the filter substrate may change during time-consuming analysis. Therefore an accurate and real time measurement method for particulate matter is the key demand for automobile industry. This paper describes a new concept for analyzing PM, which includes measurement of soot and SOF separately, as well as the total PM emission from automobile engine continuously. The concept comprises of the real-time measurement of soot emission with a diffusion charger (DC) combined with a specific dilution system. A differential flame ionization detector with separate sample line temperatures (47°C and 191°C), have been applied for the SOF measurement. The total PM is then expressed as the sum of soot and SOF mass.

A new electric powertrain and axle for light/medium trucks is presented. The indoor testing and the simulation of the dynamic behavior are performed. The powertrain and axle has been produced by Streparava and tested at the Laboratory for the Safety of Transport of the Politecnico di Milano. The tests were aimed at defining the multi-physics perfomance of the powertrain and axle (efficiency, acceleration and braking, temperature and NVH). The whole system for indoor tests was composed by the powertrain and axle (electric motor, driveline, suspensions, wheels) and by the test rig (drums, driveline and electric motor). The (driving) axle was positioned on a couple of drums, and the drums provided the proper torques to the wheels to reproduce acceleration and braking. Additionally a cleat fixed on one drum excited the vibration of the suspensions and allowed assessing NVH performance. The simulations were based on a special co-simulation between 1D-AMESIM and VIRTUAL.LAB.

This paper describes the design and certification program for a new light twin-engine aircraft. The factors considered in the design of the aircraft, the flight testing, and the changes required for certification are described. Some of the problems encountered in flight testing, and the solutions to these problems, are also discussed.

Road test simulation on test rig is widely used in the automobile industry to shorten the development circles. However, there is still room for further improving the time cost of current road simulation test. This paper described a new method considering both the damage error and the runtime of the test on a multi-axial test rig. First, the fatigue editing technique is applied to cut the small load in road data to reduce the runtime initially. The edited road load data could be reproduced on a multi-axial test rig successfully. Second, the rainflow matrices of strains on different proving ground roads are established and transformed into damage matrices based on the S-N curve and Miner rules using a reduction method. A standard simulation test for vehicle reliability procedure is established according to the proving ground schedule as a target to be accelerated.

The new generation of air disc brakes developed by PERROT is suitable for Heavy Goods Vehicles (HGVs) from classes 4 to 8. Their design, construction and function is described in this paper. In addition, it is explained in which way the brakes are tested and proven on the different test rigs and in the vehicle.

Measurement of emissions from small utility engines has usually been accomplished using steady-state raw emissions procedures such as SAE Recommended Practice J1088. While raw exhaust measurements have the advantage of producing modal exhaust gas concentration data for design feedback; they are laborious, may influence both engine performance and the emissions themselves, and have no provision for concurrent particulate measurements. It is time to consider a full-dilution procedure similar in principle to automotive and heavy-duty on-highway emission measurement practice, leading to improvements in many of the areas noted above, and generally to much higher confidence in data obtained. When certification and audit of small engine emissions become a reality, a brief dilute exhaust procedure generating only the necessary data will be a tremendous advantage to both manufacturers and regulatory agencies.

Abstract The demand for contactless, rapid manufacturing has increased over the years, especially during the COVID-19 pandemic. Additive manufacturing (AM), a type of rapid manufacturing, is a computer-based system that precisely manufactures products. It proves to be a faster, cheaper, and more efficient production system when integrated with cloud-based manufacturing (CBM). Similarly, the need for semiconductors has grown exponentially over the last five years. Several companies could not keep up with the increasing demand for many reasons. One of the main reasons is the lack of a workforce due to the COVID-19 protocols. This article proposes a novel technique to manufacture semiconductor chips in a fast-paced manner. An algorithm is integrated with cloud, machine vision, sensors, and email access to monitor with live feedback and correct the manufacturing in case of an anomaly.

The aerodynamic characteristics of automobiles have received substantial interest recently. Detailed knowledge of vehicle aerodynamics is essential to improve fuel efficiency and enhance stability at high-speed cruising. In this study, a numerical simulation has been carried out for three-dimensional turbulent flows around a commercial bus body. Also, the effect of a rear-spoiler attached at the rear end of the bus body was investigated. The Navier-Stokes equation is solved with the SIMPLE method in a general curvilinear coordinates system. RNG k- ε turbulence model with the MARS scheme was used for evaluating aerodynamic forces, velocity and pressure distribution. The results show that complex wake structure in the immediate rear of the bus body has been confirmed. The rear-spoiler modifies the near wake structure and decreases aerodynamic drag and improvement in lift force was achieved.

This paper presents a preliminary study to estimate, using on-road and laboratory tests, the mileage range of liquefied petroleum gas (LPG) as an alternative fuel for diesel-fed public utility jeepneys in the Philippines. Data from the study would be used by the Philippine Department of Energy to formulate and implement alternative fuel programs for public transport. On-road fuel consumption, load factor, and GPS speed data from selected in-use LPG and diesel jeepneys plying a chosen urban route were gathered to develop corresponding drive cycles for chassis dynamometer testing at 100% load factor were conducted to estimate an upper limit for fuel consumption. Measured on-road diesel jeepney mileage was about 6.7 km/liter at 63.5% load factor while that for LPG jeepney was 3.8-4.2 km/liter at 59.8% load factor. Drive cycle tests yielded 5.2 km/liter for diesel and 2.6-3.1 km/liter for LPG.

This paper describes a practical and efficient approach for determining complete transient, as well as steady state response of tractor-trailer air brake systems by recording pushrod displacement and air brake service line pressure as a function to time. The test hardware utilizes easy to fabricate “clip on” transducers to measure pushrod stroke length. Data acquisition is via LABVIEW‚. All transducers are easy to temporarily affix to any tractor- trailer and require no alteration to the vehicle. A complete system check takes less time than manually measuring pushrod stroke as required under FMCSA. This system with one treadle application and release gives digital timing and displacement history of all brakes. Useful information includes: application and release profiles (pushrod velocity), shoe compliance upon seating and crack pressure release points for both tractor and trailer relay valves.

A review of Reynolds number scaling and high Reynolds number simulation for commercial ground vehicles is presented. The supporting data was extracted from published wind tunnel tests, coastdown tests and computational studies for complete vehicles and vehicle components. For complex vehicles the data suggest that the use of forced transition for higher Reynolds number simulation is a viable test technique however various component specific schemes may be required to replicate the aerodynamics of a full-scale vehicle. The Reynolds number sensitivity of; boundary layer transition control, surface curvature effects, bluff base flows, wheel/tire aerodynamics, and complete vehicle aerodynamics is presented. The data show that the width-based transcritical Reynolds number for commercial vehicles is between 1 and 3 million with the averaged values for edge radius, wheels and full vehicle data sets between 1.6 and 1.8 million.

Right now, most of the industries are doing real world fuel economy test of their proto-types/mules by deploying them to city, state highways and national highways to declare their FE value. Which involves lot of unexpected problems, large amount of labor and the worst part is the pollution, traffic and uncontrolled randomness (difficulty in completing the test during festivals). Among already existing drive cycles, this is different because of a simplified mathematics of error and probabilities for method of cycle creation and it has been correlated with the real-world results. This paper reveals a 10-min city drive cycle which was created after studying most of the parameters of vehicle which may affect fuel economy and a whole method, which was devised to form this cycle and then to simplify it enough to drive.

This paper describes a study of drag reduction devices for production pick-up trucks with a body-on-frame structure using full-scale wind tunnel testing and Computational Fluid Dynamics (CFD) simulations. First, the flow structure around a pick-up truck was investigated and studied, focusing in particular on the flow structure between the cabin and tailgate. It was found that the flow structure around the tailgate was closely related to aerodynamic drag. A low drag flow structure was found by flow analysis, and the separation angle at the roof end was identified as being important to achieve the flow structure. While proceeding with the development of a new production model, a technical issue of the flow structure involving sensitivity to the vehicle velocity was identified in connection with optimization of the roof end shape. (1)A tailgate spoiler was examined for solving this issue.

An acoustic control technique for reducing booming noise caused by road surface roughness is described. This noise, mainly in the frequency range between 25 and 40Hz and accompanied by a pressure sensation, is closely related to suspension vibration characteristics and the acoustic response of the vehicle compartment. A reduction method which separates the highest acoustic response from suspension resonance in this frequency region is proposed. An acoustic simulation model is used to estimate the effects of the luggage compartment on this noise and of trunk lid vibration characteristics in optimizing acoustic properties of the compartment. As a result, a frequency region for trunk lid resonance which lowers booming noise is obtained. Estimated booming noise reduction is experimentally confirmed in road tests. A study of human auditory characteristics is also conducted to ascertain the frequency range and booming noise level which produce uncomfortable sensations.