Search Results

The objectives of this study were to obtain biomechanical responses of post mortem human subjects (PMHS) by subjecting them to two moderate-speed rear impact sled test conditions (8.5g, 17 km/h; 10.5g, 24 km/h) while positioned in an experimental seat system, and to create biomechanical targets for internal and external biofidelity evaluation of rear impact ATDs. The experimental seat was designed to measure external loads on the head restraint (4 load cells), seat back (6 load cells), and seat pan (4 load cells) such that subject dynamic interaction with the seat could be evaluated. This seat system was capable of simulating the dynamic characteristics of modern vehicle seat backs by considering the moment-rotation properties of a typical passenger vehicle, thus providing a more realistic test environment than using a rigid seat with a non-rotating seat back as done in previous studies.

High-speed biplane x-ray was used to investigate relative kinematics of the thoracoabdominal organs in response to blunt loading. Four post-mortem human surrogates instrumented with radiopaque markers were subjected to eight crash-specific loading scenarios, including frontal chest and abdominal impacts, as well as driver-shoulder seatbelt loading. Testing was conducted with each surrogate perfused, ventilated, and positioned in an inverted, fixed-back configuration. Displacement of radiopaque markers recorded with high-speed x-ray in two perspectives was tracked using motion analysis software and projected into calibrated three-dimensional coordinates. Internal organ kinematics in response to blunt impact were quantified for the pericardium, lungs, diaphragm, liver, spleen, stomach, mesentery, and bony structures.

Growth and mobility expectation in India has increased competition in the Indian two wheeler industry. Value proposition targeting improved performance, fuel economy, user-friendly features are being seen as key differentiators. The expected introduction of EFI (Electronic Fuel Injection) leads to additional system cost which needs to be justified from tangible end-customer benefits. The previous SAE papers [1] [2] attempted to provide an insight into the carbureted engine vs. fuel injection systems from fuel efficiency, combustion quality perspective and also enumerated the benefit of fuel economy to end user. To increase the benefit to the end customers, the authors propose to provide insight into innovative system concepts with interactive features. The evaluation targets the commuter segment where the implementation and acceptance potential is high.

In emergency, it is not easy to get enough fuel for generator and the usage of kerosene with small spark ignition engine for normal gasoline was investigated. As too much kerosene will cause knock, EGR (exhaust gas recirculation) system was used to reduce the knock strength. The displacement was 290cc and the compression ratio was 8.4. The knock strength was evaluated with a highpass-filtered strain sensor and 0.6V was measured at MBT (Minimum advance for Best Torque) with normal gasoline, 1800rpm, 10Nm. The engine speed was almost 1800±100rpm and the torque was almost 10±0.1Nm. As a result, the EGR system could reduce the knock strength in any kerosene mixture fuel with the control of the ignition timing.

An experimental study has been conducted at small kerosene droplet behavior near well-defined butane diffusion flame for the critical need on high efficient and cleaner energy technology. High temperature of background gas was generated using butane flame. Microflame from butane can reach the maximum temperature around 1200K at tip of outer glass. Single droplet of kerosene was injected by a small injector tube (30 μm-diameter) in to hot environment. Droplet of kerosene was released by attachment of piezo actuator on wall injector. Once the droplet is exposed to the hot atmosphere of micro flame, the temporal regression of the droplet surface was recorded. Droplet diameter was observed by CCD camera with strobe light flash at 180ns. The images captured in this experiment were analyzed by post-processing software to determine the vaporization of droplet.

Small wood biomass gasifier was developed and co-generation system supplying electric power and heat with small spark ignition internal combustion engine (SI-ICE) was investigated. The balance of electric power and heat flux will be controlled with ignition timing and the exhaust gas components were discussed. The wood biomass gasifier (downdraft type) had 105mm in inner diameter and 1000mm in length and the reaction zone temperature was 900deg-C at 68NL/min in intake air flow. The SI-ICE had 290cc in displacement and 8.4 in compression ratio and was driven at 1500rpm. The ignition angle was changed from 30deg-BTDC to 25deg-BTDC with almost same exhaust gas components. The exhaust gas temperature was from 520deg-C to 555deg-C.

The paper reviews the experimental development of fuel economy of engine powering the 2012 Formula SAE single seat race car of the University of Sophia. The balance of high power and low fuel consumption is biggest challenge of racing engine. It was found that improving the efficiency of engine by supercharging as a way to achieve that. In order to adapt the supercharger for the engine, the important design points are below: It was found that intake air blow-by gas at combustion chamber is increased in low engine speed. To improve that, the valve overlap angle was changed to adopt supercharged engine and improve effective compression ratio. Typically the racing engine demands maximum torque for performance but that does not imply that the air fuel ratio should be rich than theoretical. The point is the maximum torque of the engine is proportional to the amount of air intake. Therefore, supercharged engine is possible to increase the supercharging pressure for bigger torque.

Due to the fluctuating price of rare earth raw material in recent years, the manufacturing cost for high performance motors used in electric or hybrid vehicles becomes very difficult to control. Therefore, the automotive industries have been actively performing research and development to reduce the dependence of the rare earth magnet. The purpose of this paper is to investigate the effects of magnet arrangements at the same time to improve the magnetic circuit by increasing the reluctance torque while lowering the alignment torque in a permanent magnet synchronous motor. As a result, the amount of expensive NdFeB magnet is substantially reduced by adopting a V-shape arrangement.

In recent years, many attentions have been paid on global environmental protection and energy saving; more people, therefore, have chosen bikes for commuting to work or school. For longer distance transportation and less effort, electric power assist bikes have re-entered the market. Due to regulation of some countries, electric bikes that must be pedaled were developed. These machines utilize the pedals as the dominant form of propulsion, with the motor used only to give extra assistance when needed for hills or long journeys. The ratio of electric power to human power may affect the riding feel. As a result, a torque sensor, which detects the pedaling force, is crucial in this application. This paper proposes a new design of torque sensor by way of twist angle measurement. It is composed of a torsion bar, input and output shaft with ring magnets and Hall sensors to achieve contactless sensing.

In this study, the background gas of the droplet vaporization was concerned and simulated numerically using ANSYS fluent code. The new type, engine-like, condition of high pressure chamber and high temperature environment was considered to conduct experiment on kerosene droplet evaporation. 2D geometry of domain simulation was discretized in the very fine quadrilateral meshes. The numerical approach was solved using implicit scheme of compressible gas solver (density based). Temperature dependent properties of air are expressed for gas material properties. As the study concerning on high pressure condition the equation state of Peng-Robinson was expressed in simulation. Governing equations of mass, momentum and energy were solved by the second order upwind for flow, turbulent kinetic energy and turbulent dissipation rate. Standard k-ε model was used to solve turbulence flow in the spatial discretization.

Nowadays, cornering performance of FSAE (Formula SAE) cars are dramatically improved due to less mass, kinematic developments and tires. In such circumstance, under high speed conditions, aerodynamical devices work better. It had been decided to attach aerodynamical devices that consist of front wing, rear wing, diffuser (floor) and deflector for SR11 (Fig. 1, Table 1), a FSAE car developed by Sophia Racing (Japan). Fig. 1 SR11 Table 1Vehicle configuration of SR11 To start with developing aerodynamical devices, it had been assumed that how they work. Lap time simulation had been done with VI-car-realtime, which shows the laptime could be shorten by 2 seconds of 60 seconds for a usual FSAE endurance course with 60kgf at 60km/h downforce. Dragforce had been assumed to work well while once, it had been supposed to have a bad influence for laptime.

This paper presents the progress in Powder Metallurgy (PM) Gears, including examples of how to combine the disciplines of materials-, design- and process technology to push the limits towards increased performance, reduced weight, energy consumption and total manufacturing cost. Advancements in materials and manufacturing technology for PM gears will be presented as well as the result from simulations and reverse engineering work on existing automotive transmissions. The results from this work show that the amount and type of load on the individual gears in auto transmissions are very different and this gives room for optimized selection of material and manufacturing process.

The modern market of small engines requires low-cost solutions compatible with anti-pollution regulations. On applications without electric starter it is possible to remove the battery, but hardware and software aspects must be investigated and special solutions implemented. The main problems occur during engine fire-up (engine start), because using kick-start, only a little bit more than one engine cycle is possible for a single kick. The second aspect is that no energy is available before the crank shaft is moving, and the generator is able to supply energy to the electrical systems. Our target is to implement solutions able to start-up the ECU very quickly, ensure low consumption, and be ready to recognize engine position in the shortest possible time.

To utilize bio-butanol as an alternative diesel fuel, the effect of butanol isomer, where 1-butanol, 2-butanol and isobutanol were studied except for tert-butanol, on the combustion characteristics and exhaust emissions of butanol/gas oil blend was investigated using a DI diesel engine without modification of engine parameters. First, to understand the effect of butanol content on the diesel combustion, engine test was carried out using blends of 1-butanol which contents were 10 to 50 mass%. With increasing 1-butanol content, the Smoke emission reduces although the ignition delay gets longer and the HC and CO emissions increase especially at low load. The engine operation is stable except for full load with 1-butanol 50 mass% blend. From the above experimental results, butanol isomer blending ratio is set to 40 mass%.

In order to improve the performance and fuel economy of a reciprocating engine, it is important to reduce the overall engine frictional losses. In this paper, author conducts an experimental study on the friction characteristics due to pumping loss, valve-train system, piston assembly, auxiliaries and transmission for a 110cc, single cylinder 4-stroke gasoline engine using frictional strip-down analysis. Friction strip-down method is commonly used to investigate the frictional contribution of various engine elements at high speeds and for better understanding of the make-up of the total engine friction. The engine friction measurements for the particular engine are carried out on a motoring test rig at different engine speeds. In addition, the effect of engine operating parameters such as oil temperature and oil quantity in engine sump is also presented in detail.

Recently in North America, natural gas such as shale gas has gained much attention, and industrial SI engines are expected to fit in various fuels such as gasoline, LPG, and natural gas. Also tightened exhaust emissions regulations require industrial SI engines to adopt feedback fuel injection systems with three way catalysts. In response to these requirements of customers, we have developed a bi-fuel engine model which can be operated on any of gasoline, LPG, and natural gas. In this paper, approaches and technologies used for the development of the model are explained. On the gasoline version of the model, the locations of fuel injectors and the design of the inlet manifold with a surge tank were optimized by using Computational Fluid Dynamics (CFD). And we sought the optimum arrangement of an inlet manifold, a fuel delivery pipe, and plug-on type ignition coils.

In this study, a single cylinder diesel engine model is built via the ANSYS FLUENT CFD solver to simulate the phenomenon during each stroke. The initial conditions and boundary conditions are set based on experimental data obtained from a turbo-charged common-rail diesel engine developed by Mitsubishi. The variables that can be observed from the CFD model include cylinder pressure, gas velocity, cylinder temperature, fuel particle tracks, and mass fraction of cylinder gas components. The simulation results display the effects of the fuel injection timings on the combustion heat release process, cylinder pressure and cylinder temperature at different engine operation conditions. The pure diesel (C10H22) is adopted in this simulation study. In the FLUENT setup, k - epsilon is used in the viscous model, and the autoignition model is used to simulate the spontaneous combustion.

A large number of small size gas-fired cogeneration engines operate with homogenous lean air-fuel mixture. It allows for engine operation at high efficiency and low NOx emissions. As a result of the rising amount of installed cogeneration units, however, a tightening of the governmental emission limits regarding NOx is expected. While engine operation with further diluted mixture reduces NOx emissions, it also decreases engine efficiency. This leads to lower mean effective pressure, in particular for naturally aspirated engines. In order to improve the trade-off between engine efficiency, NOx emissions and mean effective pressure, numerical investigations of an alternative combustion process for a series small cogeneration engine were carried out. In a first step, Miller and Atkinson cycles were implemented by advanced or retarded inlet valve closing timings, respectively.

The charge stratification has been thought as one of the ways to reduce the sharp pressure rises of HCCI combustion. The objective of this study is to evaluate the potential of equivalence ratio, initial temperature, and EGR gas stratifications for reducing pressure-rise rate of HCCI combustion. Using rapid compression machine, the stratified pre-mixture is charged, and compressed to analyze the change of in-cylinder gas pressure and temperature traces during compression process. Based on the experiment results, numerical calculations by CHEMKIN are conducted to more specifically analyze the potential of equivalence ratio, initial temperature, and EGR gas stratifications on the reduction of pressure rise rate. Multi-zone model is used to simulate the thermal stratification, fuel stratification and EGR gas stratification of in-cylinder charge as like real engine.

To effectively use Computational Fluid Dynamics (CFD) for engine emission development it is necessary to be able to simulate the scavenging flow in an engine. The CFD model for a stratified charged two-stroke engine is even more complex. This model have been tuned and finally validated with engine tests. A CFD model has been made of the Husqvarna 560XP two-stroke stratified charged chainsaw engine. The model contains piston, cylinder, inlet system ducting and exhaust silencer. The simulation runs with moving deforming mesh with all ports active. The airflow levels have been fine tuned with inlet restrictions similar to those in the air filter holder, which is not completely included in the present model. The results and behaviour of the CFD model has a very good match to the measured values of the finished product. This gives us confidence in the model and several aspects can now be studied that is virtually impossible to capture by other means.