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It is effective to suppress carbon dioxide emission that engines utilize biomass fuels. Two experimental studies on the engine performances operated with a neat rapeseed oil are conducted. The first experiment is to clarify the performance of the diesel engine operated by seven kinds of neat rapeseed oil which were taken at the end of seven refinement stages in the manufacturing process. The experimental data show that the seven kinds of oil have the potential of practical application. The second experiment is to clarify the generation behavior of the deposit in the cylinder and the influence on the engine performance. The clearance volume of the tested engine was decreased until 700min, and the compression ratio was increased by the deposit generation. The Bosch smoke unit was not increased by the deposit generation. Although the slight increase in the consumption of the lubrication oil was detected, the piston ring wear was even less than that in the diesel fuel operation.

It is sometimes pointed out that Dioxins (DXNs) are contained in the exhaust gas of diesel engines. In the current stage the experimental data of DXNs from diesel engines are insufficient in order to understand their mechanism and how to reduce their generation. This paper describes the measuring results of the emitted DXNs from the diesel engine and the effect of the chlorine sources on them. The experimental result shows that the DXNs from engine and incinerator is same level when the amount of chlorine would be equalized in two combustion fields. It is found that the simple relation Y=AXB is established between DXNs concentration in the particulate matter from the diesel engine Y and the amount of chlorine in the combustion field X where the values of A and B are the expgrental constants. The relation shows it is possible to bring the DXNs from diesel engines close to the zero, if the chlorine in the motor oil and the fuel, and sea salt particles in inductien air is, cut off.

As a Birchley-Riley's fuel droplet consisted of an aqueous core embedded within a liquid fuel shell was heated in the electric furnace, the puffing and the microexplosion were observed. The waiting time for microexplosion was dominated by water content, droplet volume, fuel type and ambient temperature. When the waiting time data plot was fitted by Weibull distribution, its shape parameter was equal to 2 and the microexplosion phenomenon was classified as wear out failure type.

The lean combustion limit of methane-air mixture around gasoil sprays in the direct injection diesel engine has been measured experimentally. The experimental results show if the equivalence ratio of the mixture which is formed in the intake pipe is greater than 0.034, the mixture burns and the output power which is 15 % of calorific value of supplied methane is produced. It is confirmed that the intensity of combustion luminance which measured by using of optical fiber thermometer decreases with increasing of supplying methane. The time histories of pressure and temperature in the cylinder have been calculated by the modified two zone model which is developed to apply for diesel fumigation system. The lean combustion limit of the mixture around gasoil sprays is estimated by thismodel.

In both spark ignition engines and diesel engines, the exhaust gas recirculation (EGR) system is well known as an effective technique to reduce nitrogen oxides emissions. However, wear of piston rings and cylinder liners is sharply increased by EGR. It is widely considered that sulfur dioxide contained in exhaust gas is strongly related to wear. In order to clarify the sole effect of sulfur dioxide in recirculated exhaust gas on wear of piston rings and cylinder liners, we performed an experiment where sulfur dioxide was added to the intake air. Furthermore, we compared the amount of wear, which was measured experimentally, with the amount of sulfur dioxide absorbed by a lubricating oil film, which was estimated by a numerical model. Consequently, sulfur dioxide absorbed by a lubricating oil film plays an important role on wear of piston rings and cylinder liners.

In both spark ignition engines and diesel engines, exhaust gas recirculation (EGR) is well known as an effective technique to reduce emissions of nitrogen oxides. However, it has not yet been applied practically to heavy-duty diesel engines because the wear on piston rings and cylinder liners is increased by EGR. It is widely accepted that sulfur dioxide in burnt gas is strongly related to this wear increase. This paper proposes a numerical model to clarify the mechanism of wear which estimates the amount of sulfur dioxide absorbed by lubricating oil film. The calculated results show that the concentration of sulfur dioxide in lubricating oil film is increased with the increase in the rate of EGR and the reduction in engine speed, and is decreased with the decrease in engine load. The measured amount of wear on piston rings and cylinder liners is related to the concentration of sulfur dioxide in lubricating oil film.

In both spark ignition engines and diesel engines, the exhaust gas recirculation (EGR) system is well known as an effective technique to reduce emitted nitrogen oxides. However, wear of piston rings and cylinder liner is sharply increased by EGR. It is widely considered that sulfur dioxide contained in exhaust gas is strongly related to wear. In order to clarify the effect of sulfur dioxide only on wear of piston rings and cylinder liner, we performed an experiment on the addition of sulfur dioxide to intake air. Furthermore, we compared the amount of wear, which was measured experimentally, with that of sulfur dioxide diffused into a lubricating oil film, which was estimated by a numerical model. Consequently, it was found that sulfur dioxide absorbed into a lubricating oil film played an important role on wear of piston rings and cylinder liner.

In both spark ignition engines and diesel engines, the exhaust gas recirculation (EGR) system is well know as an effective technique to reduce nitric oxide emission. However, it has not been applied practically to heavy-duty diesel engines because wear of piston rings and cylinder liner is increased by EGR. It is widely considered that sulfur oxide in exhaust gas strongly relates to the wear. This paper presents a numerical model to reveal the mechanism of wear which estimates the amount of sulfur oxide diffused into lubricating oil film. The calculated results show that the sulfur oxide concentration in the oil layer is related strongly to the EGR rate, inversely with engine speed, and decreases under light load conditions. There is a good agreement between the results and the experimental facts.

The wear of piston rings in the diesel engines with EGR system is studied experimentally. In order to clarify the effect of PM on the wear, the wear of the piston rings in the test engine is measured, (1) when the non-soluble in the lubricating oil is removed by the oil filters, (2) when PM in the re-circulating gas is removed by the DPF, (3) when the carbon black is added in the lubricating oil. The experimental results are discussed with the measured time history of kinematic viscosity, total base number, total acid number, ZDTP survival rate, and carbon residual content and its particle size in the engine oil.

In this paper effect of on reduction a Cu-ZSM-5 catalyst of nitrogen oxides is investigated in a diesel engine. This research focuses to solve a problem that there is not enough THC to reduce nitrogen oxides in exhaust gas from a diesel engine. When diesel oil is directly supplied into the exhaust gas, the THC concentration sharply rises and the NOx conversion rate increases. The maximum NOx conversion rate reaches to 63% when the flow rate of diesel oil is 30 ml/min at a catalyst temperature 450 °C. The NOx reduction with less sacrifice of the specific fuel consumption is possible when the fuel is supplied into the exhaust pipe.