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In this paper, droplet behavior near diffusion flame was observed. Single droplet was created by thin glass tube and piezo device which pushes the side of glass tube. Dispersions of droplets location near diffusive flame were compared to droplets with no flame condition. CCD camera, strobe light with 180nsec flash time and lens of ten magnification were used for observation. Droplet pictures were taken with resolution of 0.46um/pix. As a result, droplets near diffusive flame tend to increase its dispersion of location as approaching tip of the flame. Stefan flow caused by evaporation and turbulence outer flow can be thought as causes.

This study proposes a method of decreasing the engine idle speed for the engine of FSAE race car. In general, the engine is controlled by map-based method. However, this method requires much time and cost to create a fuel injection map and an ignition timing map [1]. In addition to this, creating these maps at idle speed is much harder because the engine speed is cranky at idling. In this study, ON/OFF control and PID control were used for idle speed control without creating maps. As a result, idle speed was decreased drastically compared with map-based control. The PID control was able to stabilize the idling compared with the ON/OFF control.

The Formula SAE (FSAE) rules require mounting an impact attenuator (IA) to the front part of the formula car. The IA is necessary to take fully into account not only lighter weight of the parts but also cost effectiveness as the total cost and the workability of manufacturing have much value to win the FSAE. In this paper, three different IAs, 1) a space frame structure with steel pipes (SSF), 2) a monocoque structure with aluminum (AM) and 3) a monocoque structure with Carbon Fiber Reinforced Plastic (CFRPM), were manufactured and compared with respect to the weight and the cost effectiveness under FSAE rules. The FEM simulations for the AM were performed and the calculated results showed good agreements with the experimental ones. However, the AM could not absorb the impact energy experimentally. The CFRPM could absorb the required impact energy with lighter structure compared to other IAs. The weight was half of the experimental SSF and 1/5 of the calculated AM.

The electronically controlled shock absorber with magneto-rheological fluid, KF-MRS07, was developed for the Formula SAE (FSAE), which is an annual collegiate racing competition. The KF-MRS07 has been newly developed based on KF-NS06, a mono-tube type shock absorber produced in 2006 incorporating commercial oil. The KF-NS06 is a low cost product but hard to adjust the damping property. On the other hand, the KF-MRS07 can be controlled electronically whose damping force is changeable instantaneously while running. The equivalent viscous damping coefficient, the measure for evaluating the shock absorbers, is changed about 99% with 1.0A applied current. On-track test results show that the yaw rates can be changed from an oversteer condition to an understeer one with a simple threshold control.

This paper investigates influences of intake and exhaust valves overlap (at this duration, both of the intake valve and exhaust valve are open) on engine performance. An electric, variable cam phase mechanism (VVT, Variable Valve Timing unit) is installed in a small gasoline engine. The influences on the engine torque and BSFC, Brake Specific Fuel Consumption, are investigated on the engine bench. In addition, in case the overlaps exceeding the experimental range an engine simulator is used to predict the effects. The experimental results indicate that the VVT system can adjust the target overlap with the accuracy of 1.5deg. in a range of engine speed from 3000rpm to 7000rpm. The response time of the VVT unit was observed at the engine speed of 3000rpm. The results show that the rotation direction of motor affects on the response time of the unit. The measurement of engine torque and BSFC is performed for several overlap values at each engine speed.

The Traction Control Systems (TCS) for the FSAE car were developed with the Fuel/Ignition Cut (FIC) method and the Ignition Retard (IR) method. A slip speed was used for the TCSs and a custom Engine Control Unit (KF-ECU07) was developed with commercial devices. With the FIC TCS, the engine was stalled and the IR TCS worked better. KF-ECU07 was 7.6% of the commercial high-quality ECU in price and contributed to the cost event point gain in FSAE. The driver load was evaluated with the duration ratio of the partial throttle aperture. The duration ratio of the partial throttle aperture was 52% with the IR-TCS compared with 64% without IR-TCS and 19% driver load was decreased.

MR-damper (Magneto-Rheological fluid damper) is used an actuator with high speed in response to control the movement of four-wheel vehicles. In this paper, performances of two MR-dampers were measured. These dampers had difference in diameter of cylinder, length of piston and orifice. These changes will influence the damping force, the damping force change ratio and the response time of damping force change. As a result, a larger damper showed 1.4 times damping force change ratio of smaller one and shorter response time in compression.

Chassis performance greatly influences driving in the turn inn movement. Spec of the active damper is simulated to achieve a chassis that satisfies various requirements. In this paper, an MR-damper (Magneto-Rheological fluid damper), which is high-response active damper, is chosen. The MR-damper is mounted in FSAE vehicles and controlled vehicle behavior electronically in a simulator. As a result, the MR-damper brought a big effect to pitch action rather than roll action, and an initial damping force effected vehicle behavior more than damping force change ratio.

In recent years, effective methods of utilizing power generation using biomass have been studied a biomass power generation with an internal combustion engines. It is able to be used even on small scale. In addition, by using the ICE, it is possible to make the efficiency relatively high. The compact downdraft type gasifier was manufactured. It generates bio-syngas from biomass. A small spark ignition ICE (SI-ICE) was drove using bio-syngas as fuel. NO is included in the emission of the ICE. Due to NO is said that it pollute the atmosphere and destroy the ozone layer, it must be reduced. Many researcher study NO in emission with synthetic gas of CH4 mixed with H2. Their result is NO increased as H2 ratio increased. However, experiments with actual syngas is few. And, combustible gases in bio-syngas produced by our equipment are CO, H2 and CH4. Previous studies with synthetic gas of mixed CO, H2 and CH4 is few. Therefore, experiments are performed with actual syngas.

In internal combustion engine, it is necessary to grasp droplet evaporation for using liquid fuel efficiency and improving exhaust gas composition. However, it has not known completely yet. In this study, fuel droplet of approximately 20μm diameter that is assumed to be in combustion chamber is injected by experimental apparatus. After that, droplet goes to butane flame. We observed by high-speed camera, and experimentally considered the effects of heat flux on the fuel droplet evaporation and breakup phenomenon. For the sample fuel, we use kerosene and diesel oil. It is important for understanding evaporation condition to know temperature around droplet in butane flame. Thus, flame temperature is measured by sheathed thermocouple. Heat flux is changed by initial velocity. From experiment, we found some result. Time that from injector tube to location of breakup of the droplet is short by increasing heat flux.

Recently, alternative power generation that does not use the oil has attracted attention. There is a power generation using a biomass in one of them. However, biomass power plants is fewer in Japan. Below are two reasons why biomass power plants is few. Firstly, biomass resources are widely and thinly. So, biomass resources is a high transportation cost. Secondly, Efficiency of small biomass plant is low. Therefore, we're working with high-efficiency small biomass gasifier to the development of the power generation method. First, we generated the gas biomass by pyrolysis. Next, SI-ICE has examined whether it can be operated continuously when produced gas was thrown into the SI-ICE. In addition, when the produced gas was charged, changing the ignition timing was examined whether affect much to SI-ICE. The results of the experiment, continued operation of the SI-ICE was possible. Ignition timing was advanced, so that SI-ICE was increased efficiency and power.

The objective of this study was to determine the risk of injury to the driver during frontal impact in amateur car races. In this study, FSAE (Formula SAE, organized by Society of Automotive Engineers) was focused as car races for amateurs. In FSAE rules, the IA (impact attenuator) has to fulfill the requirements under frontal impact condition and the driver has to be held with appropriate safety harness positions. This study examined the driver's risk of injury with regard to head and chest acceleration, neck and femur loads, and chest displacement using MADYMO. Injury criteria were presented and compared for various impact pulse shapes (G-t curve) and belt restraint situations. As a result, the risk of serious injury is low in the impact conditions of FSAE rules.

In our study, phenomena is observed that 30µm droplet become breakup by UV laser irradiation. This phenomena change by composition of droplet. Then we focused on difference of absorbance, hexadecane and o-xylene are used as fuel. The former do not absorb UV enough and the latter do absorb UV enough. And authors examined the relation mixing ratio and breakup phenomena using blended fuel which consist of hexadecane and o-xylene. With regard to the UV laser we used, wavelength is 266nm, flash of time is 10nsec and laser intensity is 15mJ. CCD camera, strobe light with 180nsec flash time and lens of ten magnification were used for observation. As a result, we obtained the following; 1) A state of breakup phenomena depend on concentration of o-xylene. 2) The absorbance is not related with a state of breakup phenomena.

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.

Improvement of atomization process is one of the most effective methods to promote the cold-start period of an internal combustion engine (ICE) using port fuel injector (PFI). In this paper authors present a fuel heating method using microwave energy through the local-contact microwave-heating injector (LMI) to enhance the properties of fuel sprays in such a risky working area of ICE. Temperature and mixing ratios of blended fuel are varied and characteristics of atomization are investigated. The fuel using in experiments is blended fuel of gasoline and ethanol, the mixing ratio is varied among 0 (E0), 5 (E5), 50 (E50), and 100 (E100) percentages in volume ratio of ethanol. The temperature of the fuel is measured just before the injection by using K-typed sheath thermo-couple. Spray characteristics measured are Sauter Mean Diameter (SMD), droplet size distribution, spray cone angle, and particle size distribution width.

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.

Cylinder pressure is used for the closed-loop ignition angle control of a gasoline engine. This paper focused on the crank angle position where the maximum cylinder pressure reached (θPmax) and the relationship between the θPmax and the ignition angle. This closed-loop control set the θPmax a target value with an initial ignition angle and does not need a detailed ignition angle map. Response time and deflection with the target value are examined with a test bench. The θPmax target, ATDC 18 deg. is confirmed in consideration of the effect of knocking and the exhaust gas composition. The target ignition angle was varied step by step within a limit of upper and lower values, the response was observed and each gain was decided. At the engine speed of 5000 rpm, the duration to reach a steady value of θPmax is 0.10 s and the response time of ignition angle is 0.02 s.

Liquid fossil fuels such as gasoline, diesel oil, and kerosene are widely used as a fuel of various transportation apparatus and generating electricity apparatuses including the automobiles. The spray combustion has been widely used for internal combustion engine to use the fuel efficiently. But some parts of the phenomenon are not elucidated because this combustion method is complicated phenomenon. To elucidate this phenomenon, there are many ways of analyzing droplet. For example, observing a single droplet which suspended by a catenary or under the microgravity. However, those methods are not enough simulation of a real droplet in the internal combustion engine. In this study, we developed an apparatus which could inject a freedom droplet of diameter about 30µm. It is considered that the droplet is in a real internal combustion engine. And the apparatus was installed in a container which could realize elevated temperature and pressure.

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.

The simplified shift/clutch operation system, KF-TOS-P, was driven by DC motors (DC12V driven) with a microprocessor. Two rotary sensors detected the positions of the shift lever and the clutch lever. In FSAE rules, the simple throttle-by-wire is prohibited and the engine speed was controlled by the drivers. The custom steering wheel, KF-SW07 as the human machine interface, was designed and manufactured with CFRP by VaRTM (Vacuum assisted Resin Transfer Modeling) method. The shift operation time of KF-TOS-P was half of the manual operation and the clutch engagement time of that was 25msec. KF-SW07 was 22.6% weight and 16.7% cost (calculated by FSAE rules) of the commercial steering wheel of the race use.