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Ford's H2RV (Hydrogen Hybrid Research Vehicle) uses a Hydrogen fueled Internal Combustion Engine. This engine has a higher compression ratio and a faster fuel-burning rate compared to a conventional gasoline engine. The conventional flywheel is replaced with an electric motor in the hybrid powertrain, which causes higher crankshaft torsionals and is a major NVH source. The engine has a centrifugal supercharger mounted on its front-end dress, which is a big source of NVH. Fans are used to cool the high voltage batteries and to provide ventilation of H2 in the case of a leakage. The body sheet metal has several holes for passive H2 ventilation, battery cooling, plumbing lines, and harness routing. Underhood hardware, due to the hybrid transmission and the H2 ICE, created major packaging challenges for the intake and FEAD NVH. The exhaust muffler volume was limited due to the installation of high voltage batteries and underbody H2 fuel tanks.

The concept of the Modular Hybrid Transmission (MHT) is to use a production transmission design with modifications to create a new low investment cost parallel hybrid-electric powertrain. In the MHT system to be discussed, the torque converter has been replaced with a 40-kilowatt electric induction machine, which is coupled to a 300 volt - 3.6 Ah Lithium-Ion battery in a 1450 kg vehicle. Also, an added wet clutch system allows the engine to be disconnected from the electric machine enabling “electric only” driving. The drivability problems occur when the driver's desire to accelerate changes quickly and the engine is still shut down. This situation can occur both from rest and while already moving.

There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.

Li-Ion battery is attractive for HEVs and FCEVs because of its high power density and lack of memory effect. However, high battery temperatures during operation result in a short battery lifespan and degraded performance. To address this issue, battery manufacturers and OEMs have used different pre-set cooling strategies. Unlike the pre-set cooling strategy this thermal model forecasts battery temperatures, allows a better usage of the battery system, responds to battery power demand and maintains battery temperature limits. This paper discusses the real-time control of the battery cooling including battery stress analysis. The authors present a dynamic thermal model for the Li-Ion battery system using the finite-volume method and discuss transient battery thermal characteristics and real-time battery cooling control under various battery duty cycles. Validation results of the model are presented in this paper.

The performance of structure-borne road NVH can be cascaded down to three major systems: 1) vehicle body structure, 2) chassis/suspension, 3) tire/wheel. The forces at the body attachment points are controlled by the isolation efficiency of the chassis/suspension system and the excitation at the spindle/knuckle due to the tire/road interaction. The chassis force transmissibility is a metric to quantify the isolation efficiency. This paper presents a new experimental methodology to estimate the chassis force transmissibility from a fully assembled vehicle. For the calculation of the transmissibility, the spindle force/moment estimation and the conventional Noise Path Analysis (NPA) methodologies are utilized. A merit of the methodology provides not only spindle force to body force transmissibility but also spindle moment to body force transmissibility. Hence it enables us to understand the effectiveness of the spindle moments on the body forces.

Velocity profiles for air flowing under a vehicle body are determined by analyzing videotapes of neutrally buoyant soap bubbles using motion analysis software and equipment. What had heretofore been primarily a qualitative flow visualization technique has been extended to provide quantitative data. The light sources, cameras, and bubble generator, mounted on the vehicle, are powered by the vehicle's electrical system, making it possible to compare underbody velocities measured in a wind tunnel with those over the road. Results are presented for a heavy-duty 4×4 pickup truck at speeds up to 25m/s (55 mph). The velocity profiles in the tunnel and on the road were quite similar.

Do older light trucks, often with second (and subsequent) owners, present a higher risk to either their own occupants or to other road users? And is the safety record for newer trucks better or worse than the record for their older counterparts? To answer these questions, fatalities in crashes involving at least one light truck were examined using the Fatal Analysis Reporting System (FARS). Fatality rates for both occupants of the light truck and for other road users (occupants of other motor vehicles, pedestrians, etc.) in these crashes were computed, based both on the number of registered vehicles and on the vehicle miles of travel. Two trends in these fatality rates are observed. First, as light trucks age, a consistent decline is found in risk both to their own occupants and to other road users. Second, a distinct decrease is found in road user risk for newer light trucks compared to older light trucks when they were new, both for their own occupants and for other road users.

This paper describes the design and build of an experimental super transport truck for high-speed, long distance freight hauling on the interstate highway system of the 1970's. The tractor, powered by a 600-hp gas turbine engine, pulls two 40-foot tandem axle trailers at a G.C.W. of 170,000 lbs. Details of the turbine engine development are covered in SAE paper, No. 991B. One of the features of the super transport truck is the cab, which is designed for long-distance, non-stop, two-man operation. It is provided with sleeping accommodations, washroom conveniences, food facilities, and a complete heating and air-conditioning system. The 13-foot high cab roof is flush with the top of the trailers, providing a substantial aerodynamic advantage. Other features and components of the truck are described, and observations made during the 5500-mile national tour are discussed.