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Measurements of crank angle resolved air velocity and fuel droplet velocity inside the intake port of a six cylinder four valve production engine were performed using two component Laser Doppler Velocimetry (LDV). Prior to the engine measurements the fuel injector was characterized by determining time resolved droplet sizes and velocities with Phase Doppler Velocimetry (PDV) at an injector test rig with complete optical access. PDV results indicate that during spray penetration into quiescent air at atmospheric pressure (test rig conditions) large droplets move at the tip of the spray while small droplets due to their low force of inertia are slowed down by aerodynamic pressure and pile up at the end of the spray. Mean values of the droplet diameter rise with the distance from the injector because the smallest droplets do not reach the downstream measurement locations.

This paper describes a study of the incidence of drug use among drivers and pedestrians killed in fatal crashes in Melbourne. Australia. Overall, 42% of the study population had been drinking and 66% had used drugs other than alcohol, caffeine and nicotine. Blood alcohol concentration was significantly related to the road users' liability for the crashes in which they were killed. However, there was no relationship between liability and use of other drugs. Only 11% of the study population had used alcohol in combination with other drugs and individuals with zero blood alcohol levels were more than twice as likely to have used other drugs as those who had been drinking. No drinking road users who were deemed not liable for the crashes in which they were killed had combined alcohol with use of other drugs. The implications of these data to development of relevant countermeasures to crashes in which cannabis or medication are factors has been discussed.

The aim of this study is systematically to evaluate and quantify the influence of interaction of car passengers in impacts. Within this programme 70 car tests were performed. The impact speeds were 30 and 60 km/h for the frontal and rear and 30 and 45 km/h for the lateral impacts. Impact angles were as follows: frontal: 0° and 30° left; lateral: 60° and 120° left, 90° right; rear: 180° and 150° left. Test cars were of subcompact type bought on the car market. Impacting vehicle was a rigid moving barrier according to SAE J 972a. Each of the 14 configurations was repeated 5 times. The effects of interaction were studied on 50 percent male PART 572 dummies. The significant effect of interaction is the change of direction of acceleration in the additionally loaded occupant, because the interaction forces are effective in the opposite direction of the primary impact forces.

The aim of this study is to evaluate the interaction of car passengers in side collisions. In 12 side impact tests, four newly developed side impact dummies (APROD 82, HSRI, MIRA, ONSER) were positioned at the impact side of the car, with the interacting dummy - a Hybrid II dummy - on the offside. The velocity of the impacting rigid barrier was 45 km/h. Each test configuration with each side impact dummy was repeated three times. They are compared with tests of the same configuration but without an interacting Hybrid II dummy. The kinematics of the side impact dummies are more humanlike in side impacts than those of the Hybrid II dummy which was used in a previous test program on the impact side. Each side impact dummy showed interaction effects and loads in different measuring parameters.

Traffic flow rates and speeds have been measured on two types of road to determine how CV's affect traffic flow. A comparison of the behaviour of CV and car drivers during braking was also made

This study reflects on two areas of vehicle aerodynamics, optimising cooling performance and features that will improve the handling of the car. Both areas will have a significant impact on the overall performance of the car and at the same time these areas are linked to each other. The considered vehicle in this study was the Chalmers Formula Student 2011 Formula SAE car and the flow field was analysed using both numerical simulations as well as performing wind tunnel experiments on a 1:3-scale model of the car. The focus on increasing downforce without increasing the aerodynamic drag is particularly good in Formula SAE since fuel economy is an event at the competition. Therefore, the intention of this work is to present a study on how undertrays with different design such as added foot plates, diffuser and strakes can improve the downforce and reduce the drag.

The four-screw propulsion vehicle has high traffic performance and strong maneuverability on the fluidized soft terrain. However, the interaction mechanism between the four-screw vehicle and the soft terrain is quite complicated. The driving performance of the screw vehicle on the soft terrain are not clear, and it is difficult to achieve accurate dynamic control of the four-screw vehicle. The mechanical relationship and motion mode of the four-screw propulsion vehicle-soft terrain interaction are theoretical analyzed, the force characteristics of the screw drive wheel under each motion mode of the vehicle are obtained. The interaction model between soft terrain of tailings dam and four-screw vehicle is established by using smooth particle hydrodynamics (SPH) and finite element method (FEM).

Due to the design of lightweight, high speed driveline system, the coupled bending and torsional vibration and rotordynamics must be considered to predict vibratory responses more realistically. In the current analysis, a lumped parameter model of the propeller shaft is developed with Timoshenko beam elements, which includes the effect of rotary inertia and shear deformation. The propeller shaft model is then coupled with a hypoid gear pair representation using the component mode synthesis approach. In the proposed formulation, the gyroscopic effect of both the gear and propeller shaft is considered. The simulation results show that the interaction between gear gyroscopic effect and propeller shaft bending flexibility has considerable influence on the gear dynamic mesh responses around bending resonances, whereas the torsional modes still dominate in the overall frequency spectrum.

Nineteen sled impact tests were conducted simulating a frontal collision exposure for an unrestrained driver. The deceleration sled buck configuration utilized the passenger compartment of a late model compact passenger vehicle, a rigid driver's seat, and a custom fabricated energy-absorbing steering column and wheel assembly. Sled impact velocities ranged from 24.1 to 42.6 km/hr. The purpose of the study was to investigate the kinematic and kinetic interaction of the driver and the energy-absorbing steering assembly and their relationship to the thoracic/abdominal injuries produced. The similarities and differences between human cadaver and anthropomorphic dummy subjects were quantified.

The in-cylinder charge motion during the compression stroke of an optically accessible engine equipped with direct injection of hydrogen fuel is measured via particle image velocimetry (PIV). The evolution of the mean flow field and the tumble ratio are examined with and without injection, each with the unmodified 4-valve pent-roof engine head and with the intake ports modified to yield higher tumble. The measurements in the vertical symmetry plane of the cylinder show that intake modification produces the desired drastic increase in tumble flow, changing the tumble ratio at BDC from 0.22 to 0.70. Either intake-induced flow is completely disrupted by the high-pressure hydrogen injection from an angled, centrally located single-hole nozzle. The injection event leads to sudden reversal of the tumble. Hence the tumble ratio is negative after injection. However, the two intake configurations still differ in tumble ratio by about the same magnitude as before injection.

This paper aims to study numerically the influence of the number of fuel sprays in a single-cylinder diesel engine on mixing and combustion. The CFD simulations are carried out for a heavy-duty diesel engine with an 8 hole injector in the standard configuration. The fuel spray mass-flow rate was obtained from 1D-simulations and has been adjusted according to the number of nozzle holes to keep the total injected fuel mass constant. Two cases concerning the modified mass-flow rate are studied. In the first case the injection time was decreased whereas in the second case the nozzle hole diameter was decreased. In both cases the amount of nozzle holes (i.e. fuel sprays) was increased in several steps to 18 holes. Quantitative analyses were performed for the local air-fuel ratio, homogeneity of mixture distribution, heat release rate and the resulting in-cylinder pressure.

Rapid opening, closing and rebounds of needle from seat and stopper plate give rise to fluid transients in fuel injectors, which are strongly coupled to the dynamics of needle and body motions. A mathematical model, based on unsteady compressible flow in the injector and steady incompressible flow in inlet and outlet section in conjunction with the equation of motion for needle and body, allows the quantitative description of the injector operation cycle. Agreement between prediction and experiment in terms of needle motion, needle velocity and pressure history is good. The mathematical model is used to show the effects, which various contributions to the hydrodynamic interaction force have on the needle motion, on pressure history and on injected mass.

The theme of this work is the interaction of the part geometry, material properties, forming severity and tooling design for box-shaped stampings. It is shown that the forming severity decreases with the increase of material normal anisotropy and corner radius. The lower the material normal anisotropy, the larger are the required tooling clearances and the thickening of the material under the blankholder. Understanding these relationships is of primary importance in applications requiring a major change in material properties, such as cold-rolled to hot-rolled conversion of products, or product shape redesign. The work also introduces a new type of idealization to metal forming problems. Beside the traditional continuum mechanics axisymmetric and plane strain idealizations, the work introduces the “corner analysis” approximation.

Performance and emissions comparisons have been made between helical and directed ports for a range of injection rates. The tests were carried out on a single-cylinder research engine of 120 mm bore with a cylinder head capable of accepting interchangeable inlet ports. An important feature of the work was optimisation of the nozzle specification for each combination of port and pumping rate. The aim was to assess the advantages of each port design under various conditions. The results showed that similar performance and emissions could be achieved by both helical and directed ports.

The requirement to meet more stringent emission standards has focused attention on the effects of gasoline sulfur on automotive emissions. Numerous studies have shown that three-way catalyst performance is severely inhibited by sulfur. A literature review of laboratory studies on the interaction of sulfur with automotive catalyst components provides the basis for understanding impacts on catalyst activity under the variety of conditions encountered in vehicle operation. Under stoichiometric and rich conditions, SO2 formed during combustion is dissociatively adsorbed on platinum group metal surfaces to form strongly bound Sad. Sulfur inhibition results from both physical blockage and electronic effects of Sad, such that low coverage of Sad results in disproportionately higher levels of reaction site blockage. This is responsible for the nonlinear effects observed with increasing fuel sulfur level.

The results of experimental investigation of the icing processes of NACA 0015 airfoil are presented. The experiments have been carried out with the help of a high-speed camera at the icing/deicing facility at the Institute of Adaptronic and Functional Integration of the Technical University of Braunschweig. The investigation objective is the study of interaction between supercooled large droplets and the icing airfoil surface as well as physical phenomena occurring during the icing process. Evolution of the initial phase of ice growth process over time is observed, the general structure of ice accretion and its alteration along the airfoil is examined. Experiments have been carried out within a wide temperature range. Photos of the specific moments of the icing process have been analyzed. Splashing events and water movement on the icing surface have been observed.

In this work the effects of vehicle vertical vibrations on the tires/road cornering forces, and then consequently on vehicle lateral dynamics are studied. This is achieved through a ride model and a handling model linked together by a non-linear tire model. The ride model is a half vehicle with four degrees of freedom (bounce and pitch motions for vehicle body and two bounce motions for the two axles). The front and rear suspension are a hydro-pneumatic slow-active systems with 6 Hz cut-off frequency designed based on linear optimal control theory. Vehicle lateral dynamics is modeled as two degrees (yaw and lateral motions) incorporating a driver model. An optimal rear wheel steering control in addition to the front steering is considered in the vehicle model to represent a Four Wheel Steering (4WS) system. The tire non-linearity is represented by the Magic Formula tire model.

We study, herein, the steady, isobaric two-dimensional interaction with a flat perpendicular wall of an otherwise planar fuel-lean hydrocarbon-air premixed laminar flame, stabilized on a heat-sink burner. We report isotherms, and isoconcentration contours for hydrocarbons, in the quench layer on a cold isothermal side wall from results of numerical (ADI) integration of the elliptical boundary-value problem for a one-step irreversible Arrhenius-type chemical reaction. Also, burning near a single hot or adiabatic wall, and reduction of flame speed in a parallel-plate crevice-type duct with cold walls, are discussed.

This paper presents a parametric study that utilized the CVS/ATB multi-body simulation program to investigate the interaction of the hand and wrist with a door handgrip during side air bag loading. The goal was to quantify the relative severity of various hand and handgrip positions as a guide in the selection of a test matrix for laboratory testing. The air bag was represented as a multi-body system of ellipsoidal surfaces that were created to simulate a prototype seat-mounted thorax side air bag. All simulations were set in a similar static test environment as used in corresponding dummy and cadaver side air bag testing. The occupant mass and geometric properties were based on a 5th percentile female occupant in order to represent a high-risk segment of the adult population. The upper extremity model consisted of wrist and forearm rotations that were based on human volunteer data.

In air bag tests without a restraining seat belt (FMVSS208) several users of the Hybrid III dummy have reported a pelvic interference problem during the tests. An insufficient range of motion and a hard metal to metal contact between the pelvis and femur has lead to unexpected chest acceleration waveforms. The paper gives a mechanical analysis of this phenomenon, explaining how the forces acting on the dummy lead to a rotation of the pelvis and femur and how forces arise between the pelvis and the chest. Finally two sample tests where the pelvic interference problem has occurred are presented.