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An experimental campaign based on the harness and Event Data Recorder (EDR) of a production vehicle (Toyota Auris 2007, Generation 02EDR) was setup for laboratory experiments. The experiments involved triggering non-deployment events in the EDR by hitting the Airbag Control Module (ACM) with a pendulum style impactor with different pendulum weight, in frontal and rear directions and at different initial angles. The ACM was hit in three different conditions: ACM fixed, ACM free to move and ACM launched towards impactor. The wheel speed sensors were emulated with the same 7/14 mA pulses such that the vehicle was simulated to be moving with a ramping up and down speed during the impact. This was done such that the EDR data has vehicle speed in both its pre and post-crash data. The Bosch Crash Data Retrieval (CDR) tool was used to download the EDR data. Data from these experiments is shown and discussed. An in-house built sniffer was utilized to filter and store the relevant CAN bus data.

The layout of a vehicle steering system has to resolve a compromise. While it is important for lateral vehicle control to feel steering torque feedback of lateral tire to ground interaction, disturbing forces shall not be present in the feedback steering torque. These disturbing forces result from road irregularities, wheel rotor imbalance, suspension asymmetry caused by production tolerances, wear or impacts, and additional vehicle internal forces, e.g. the steered wheels also driven by the engine or braked. In general these disturbances are reduced by an optimization of the suspension geometry to decrease the impact of the unintended forces on the steering system. The remaining disturbance is controlled to an acceptable level via force feedback sensitivity calibration of the steering system, what in return influences the intended driver sensitivity to feel lateral tire forces.

The object of this paper is to give to American automobile engineers some indications of the trend of engineering designs adopted in the latest British and European passenger cars, and of the recent developments incorporated in them. The special items dealt with include engines, transmissions, brakes, and suspensions, as well as other features. It is felt that a critical period has been reached in connection with the more widespread adoption of automatic transmissions and disc brakes on British and European cars, and this position is reviewed in some detail.

This paper presents a review on pedestrian impact reconstruction methodology and offers a comprehensive review of the literature. Several types of analyses are discussed which can be used to reconstruct the accident scenario using the facts collected from the scene. Inclusive in this review is the utilization of skid mark analysis, debris analysis, injury/damage match-up, trajectory analysis, nighttime visibility, and alcohol effects. The pedestrian impact reconstruction methodology is illustrated with a real world case example to point out different observations which can provide insight into the pedestrian/vehicle collision reconstruction approach. The literature review provides a broad foundation of information on pedestrian impact reconstruction and can be used to supplement the techniques presented in this paper in areas related to pedestrian impact. Research advances in the area of pedestrian impact reconstruction are also discussed in this paper.

The electrical connection between chassis and steering wheel which is used for igniting and monitoring the driver's airbag and also for transmitting horn and other signals today takes the form of a galvanic contact - in other words, an electrically conductive connection. In virtually every case multiple elastic contacts resembling clock springs are used but very occasionally slip rings are still used. Contactless electrical connection would present a wide range of benefits here and would not cost any more. In the case of an AC airbag firing system the usual capacitative coupling would be replaced by the new inductive system. The use of a magnetic compound material means virtually lossless transmission up to higher transmission frequencies and a comparatively simple manufacturing process.

The purpose of this paper is to document the application to date, of Synthetic Dielectric Coolant Fluid, MIL-C-87252, in the liquid cooling system of the F-22 Advanced Tactical Fighter Environmental Control System / Thermal Management System (ECS/TMS). This fluid consists of a filtered polyalphaolefin (PAO) base stock that is blended with certain anti-oxidant additives. This paper describes the ECS/TMS liquid cooling system, discusses the rationale for choosing MIL-C-87252, and the lessons learned to date regarding the practical application of this fluid in the F-22. The topics discussed are potentially applicable to all liquid cooling systems.

The fuel consumption and the emissions of modern passenger cars are highly affected by the fluid and material temperatures of the engine. Unfortunately, the high thermal efficiencies of Direct Injection (DI) Diesel and Spark Ignition (SI) engines cause in many driving situations low heat transfer to the engine components and especially to the oil and the coolant. In these conditions the normal operating temperatures are not achieved. Especially at low ambient temperatures and low engine loads the requirement of a comfortable cabin heating and a fast warm-up of engine oil and coolant cannot be satisfied simultaneously. To reach the required warm-up performance, an Exhaust Heat Recovery System (EHRS) will be demonstrated. Further design and optimization processes for modern cooling systems in fuel-efficient engines require numerical and experimental investigations of supplemental heater systems to meet all requirements under all circumstances.

In conventional automobile designs, a radiator for cooling the engine and a condenser for condensing the air-conditioner refrigerant are typically configured independently of each other; they are usually mounted in series in the front of the engine compartment so that they will receive sufficient air flow while the vehicle is running. We have developed a smaller and higher performance cooling module by integrating these two heat exchangers into one unit. (Fig 1) For the heat dissipation fin, we have employed an integral fin construction equipped with an insulating slit, resulting in effective prevention of thermal conduction from the higher temperature radiator side, to the condenser side. We also succeeded in improving heat dissipation performance by making effective use of the connection part of the integral fin.

Considerable research has been dedicated to establishing the amount of energy absorbed during different types of collisions. In the early 1960’s, motor vehicle manufacturers began conducting barrier crash tests consistent with SAE suggested procedures. This allowed investigators to establish the amount of energy that went into metal deformation in the tested vehicle. Over the years, there have been many advances in establishing the amount of crush energy in a particular accident, including the development of several computer programs. Four two-vehicle, single-moving rear-impact crash tests were conducted to compare the effect of override and offset. Override comparisons were made using a moving, rigid barrier or a heavy truck as the impactor, and each pair of tests having either offset or full rear engagement. All four tests were conducted using a like make and model four-door sedan as the target vehicle. Each test had the same available crush energy for the car.

A suction line heat exchanger (SLHX) transfers heat from the condenser outlet to the suction gas. In a TXV (thermostatic expansion valve) system, the performance improvement with a 60 to 80 % effective SLHX is expected to be on the order of 8 to 10 % for capacity, and 5 to 7 % for COP for high outdoor air temperatures of 43ºC. In a FOT (fixed orifice tube) system, the performance improvement was calculated to be about 10 to 15 %. The calculated improvements have been verified experimentally within a few percent.

Having a light weight, a good heat conductivity and a good brazability, aluminum alloy is widely used for automotive heat exchanger systems. The major problem with Aluminum is perforation of the tube by pitting corrosion and corrosion protection is necessary in the field. In radiator and condenser systems using the the Nocolok brazing process given good corrosion resistance using cathodic protection with sacrificial anode made of Zn-sprayed onto tube or low corrosion potential fins etc. On the other hand, in drawn-cup type evaporators, that are fabricated from brazing sheet tubes in vacuum brazing method and then covered low electro-conductive drain water film in operation, the effect of cathodic protection by the anode fin is limited to a very small area. Therefore, this has been studied to improve self-corrosion resistance of the core in the brazing sheet tube.

Applying nanotechnology to thermal engineering, ANL has addressed the interesting and timely topic of nanofluids. We have developed methods for producing both oxide and metal nanofluids, studied their thermal conductivity, and obtained promising results: (1) Stable suspensions of nanoparticles can be achieved. (2) Nanofluids have significantly higher thermal conductivities than their base liquids. (3) Measured thermal conductivities of nanofluids are much greater than predicted. For these reasons, nanofluids show promise for improving the design and performance of vehicle thermal management systems. However, critical barriers to further development and application of nanofluid technology are agglomeration of nanoparticles and oxidation of metallic nanoparticles. Therefore, methods to prevent particle agglomeration and degradation are required.

The present study is an experimental investigation on the influence of engine operational parameters on the temperature history of intake valves. During the initial stage of the warm-up process, the temperature history of the intake valve followed an exponential behavior with a time constant that ranged from about 23 to 39 s for the test conditions examined. In contrast, the temperature history of the coolant varied linearly with time suggesting that the net heat input to the coolant is roughly constant during the initial stage of the engine warm-up process. After the initial transient phase that lasted about one minute, the temperature rise of the intake valve was quasi-steady. During this latter period, the measured intake valve temperature was predicted by the steady-state temperature correlation developed in an earlier study.

Optimizing heat protection for underbody and underhood components, using non-CFD heat transfer CAE tools, requires the estimation of local convective heat transfer coefficients. This estimate, in turn requires knowledge of the local air velocity. Currently available methods for obtaining this velocity at several vehicle locations have been impractical and expensive for use in over-the-road testing. This paper presents the design, fabrication, and field testing results of a 26 mm diameter spherical transducer which measures the local heat transfer coefficient directly. The transducer contains three thermocouples and a heater. It is calibrated to correlate the coefficient with the air velocity. Drawing less than 0.1 A, a number of them can be powered by the vehicle battery with negligible drain. The data acquisition consists of sampling three thermocouples per spherical transducer.

Condensate that forms on the air side surface of an evaporator can have a significant impact on the air side performance of brazed aluminum, louver fin automotive evaporators. Condensate can “bridge” the space between two adjacent fins or louvers and alter the flow of air through the evaporator, causing a change in the heat transfer and friction characteristics. This study attempts to determine how condensate drains from an evaporator in the hopes of improving the air side fin geometry and obtain an evaporator that retains a minimum amount of condensate. Using a table-top wind tunnel apparatus, qualitative observations of condensate draining from a single column of louver fins brazed to a refrigerant tube were made. The amount of condensate retained in an evaporator core was determined using the experimentally-verified dip test method.

Aluminum alloy heat exchangers use chromium (VI) compound for their surface treatment to prevent white rust. The use of chromium (VI) compound is restricted and will be banned worldwide in view of environmental concerns. Therefore, we need a timely change to the non-chromate type treatment. Considering this trend, we have developed and released non-chromate type heat exchangers. In addition to high corrosion resistance, these heat exchangers feature a good hydrophilic ability, antibacterial activity, and smell preventing property. With simultaneous development activities at the development and design divisions, as well as making good use of the quality function deployment (QFD) method into the total process from design work to production we have completed the project in a short time.

The advancements in hybrid and electric vehicles require an optimal utilization of the on-board energy sources to increase vehicle fuel economy, provide a safe and comfortable driving environment, and extend heating and cooling capacity range. Recently, the application of parallel propulsion technology to design and build hybrid vehicles has caused new concerns on climate control engineering. This study is the first to address the challenges on developing an innovative heating system for parallel hybrid vehicle applications. This paper presents a hybrid heating system for a parallel hybrid passenger car, in which a conventional coolant heater core loop and a heat pump loop are installed to meet the needs of cabin heating. Thermodynamic characteristics of various subsystems are discussed with respect to the variations of ambient temperature through the experimental and analytical comparisons.

The designer of mobile air–conditioning systems must consider the total vehicle in order to provide occupant comfort. An effective refrigerant circuit is only one portion of the vehicle “Comfort System” and without the system's ability to deliver adequate cooling it will not meet the consumer's expectations. A significant considered is the design of the vehicle's body, including the panel outlets and the extent of window glazing surfaces. The location of the panel outlets to provide the occupant's adequate and controllable system airflow for changing weather conditions is a major factor in achieving comfort. Window glazing locations and areas have a major effect on increasing the air–conditioning thermal load by allowing direct solar radiation into the vehicle. Unfortunately, the styling of the vehicle dictates these areas and these constraints very often result in the customer having an air–conditioning system that provides an unsatisfactory level of performance.

Simulation of passenger compartment climatic conditions is becoming increasingly important as a complement to wind tunnel and field testing to help achieve improved thermal comfort while reducing vehicle development time and cost. Delphi Harrison Thermal Systems has collaborated with the University of California, Berkeley to develop the capability of predicting occupant thermal comfort to support automotive climate control systems. At the core of this Virtual Thermal Comfort Engineering (VTCE) technique is a model of the human thermal regulatory system based on Stolwijk’s model but with several enhancements. Our model uses 16 body segments and each segment is modeled as four body layers (core, muscle, fat, and skin tissues) and a clothing layer.

In recent years, concern among car users regarding air quality has been steadily increasing. Pollen and diesel vehicle exhaust gases entering the cabin and smoke from fellow passengers not only reduce the quality of experience for everyone in the car, but are also harmful to the health. Therefore, we developed: 1 A low pressure loss, dust-removing, selectively deodorizing filter that effectively absorbs malodor from diesel vehicle exhaust gas, without affecting A/C performance. 2 An automatic intake door control system that excludes outside exhaust gas 3 An optic catalytic air purifier with germ removal and long life deodorizing functions. We here report on the system combining these functions.