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The ideal torque curve of automotive engines should be high and flat from low engine speed. To achieve this, we installed a variable nozzle turbine (VNT) turbocharger to a retail natural aspirated (NA) small gasoline engine. In the VNT turbocharger, variable vanes are set around the turbine wheel and form nozzles that changed the flow velocity of the exhaust gas. The vane position was controlled to adjust intake pressure at a target. As a result, the maximum torque improved by 27% and the engine speed at maximum torque was lowered by 1550rpm. A flat torque curve was achieved from 5450rpm to 8000rpm.

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.

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.

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.