Review 17 (1996) 83-99
In this study the new water injection system was applied to an 11 liter natural aspirated DI diesel engine. In the system, water and fuel were arranged in the order of fuel, water and fuel in a nozzle during interval of injection and were injected into the cylinder in the same order. The result showed that NOx reduction was directly proportional to the rate of water to fuel regardless of engine speed and load, and that in Japanese 13 mode test NOx and PM could be reduced by 50% and by 25% respectively without penalty of fuel consumption.
Products from Diesel Formation Process of Combustion Engines by Numerical Simulations - 1st Report Application to NOx Formation Analysis under Various Combustion Control Conditions -
Hajime Ishii, Hisakazu Suzuki, Matsuo Odaka (Traffic Safety and Nuisance Research Institute, Ministry of Transport) NOx formation analysis by numerical simulation was studied under various engine operating conditions. There was good qualitative correspondence between experimental and numerical results in this analysis. The simulation was applied to diesel lean combustion, in which pre-mixed fuel was supplied to intake air, to be operated under uniform mixture compression ignition. As a result, it was predicted that it was possible to reduce NOx by means of diesel lean combustion.
Generation of Hydrocarbon Emissions from a Direct Injection Diesel Engine J.C. Dent (Loughborough University of Technol-
ogy), Yoshiyuki Kidoguchi (Komatsu Ltd.) The generation of unburned hydrocarbon emissions due to physical effects was studied using KIVA-II. The results showed that exhaust hydrocarbons increase due to poor mixing of fuel with air during the ignition delay period in the low swirl case, and bulk quenching due to high mixing rate and high heat loss to the wall during the combustion and expansion processes in the high swirl case. The re-entrant combustion chamber is advantageous for unburned hydrocarbon emissions in the case of retarded injection timing, but this modification produces excessive mixing and bulk quenching for advanced timing and, as a consequence, higher unburned hydrocarbon emissions. 9539275
with High Pressure
slow flame propagation under low load conditions due to too fuel-lean mixtures. We have developed a new type fuel injection nozzle, called “slit nozzle.” to resolved those problems. This nozzle has a single oblong nozzle vent like a slit, expected to make a concentrated and homogeneous methanol spray around the glow-plug. This paper deals with the effect of slit geometries on ignition, combustion and exhaust gas emission characteristics. The results indicate that slit geometries including width, spray angle and the glow-plug temperature greatly influence ignition delay time. A wider slit causes higher combustion pressures and lower ignition sensitivity to the glow-plug temperature due to more highly concentrated methanol spray around the glow-plug.
Effect of Injection Nozzle Hole Diameter on Combustion of a DI Diesel Engine under Supercharging and EGR Conditions
Hisakazu Suzuki, Noriyuki Koike, Matsuo Odaka (Traffic Safety and Nuisance Research Institute, Ministry of Transport) For further reduction of NOx and particulate emissions from a direct injection (DI) diesel engine with a Supercharger and EGR system, the effects of a fuel injection process using smaller hole nozzle was studied. As a result, it was shown that both NOx and particulate emissions could be reduced simultaneously under supercharging and EGR conditions. The combustion phenomena and emission performance was also analyzed using a high speed video camera and an endoscope technique.
The New Supercharged Engine, ZTZ-FZE, for Mini-van 9539310 Tetsushi Suzuki, Nobuhiko Kakeno, Eiji Ito, Chikara Hayashi, Hisao Nishiguchi, Yasushi Hamada (Toyota Motor Corporation) We have developed a supercharged 2.4liter 16-valve in-line four-cylinder engine, 2TZ-FZE, for TOYOTA mini-van PREVIA in U.S.A ESTIMA in Japan. In spite of the air-charged engine, linear acceleration and low fuel consumption were realized by the newly developed intake air pressure control system. A supercharger outlet duct with a resonator and an air tube made of a new plastic material reduced the supercharger noise. As a result, the new Previa with 2TZFZE has higher performance, lower fuel consumption and more comfort than other mini-vans with larger V6 engines.
Injection - Application of Small Diameter Combustion Chamber and High Swirl - Yasuhiro Tabata, Yoshinaka Takeda, Keiichi Niimura (New ACE Institute Co., Ltd.) A new concept of diesel combustion improvement with high pressure fuel injection, that is, promoting fuel spray diffusion by early stage impingement upon cavity wall and performing the fuel spray homogeneous with high air swirl to mix impinged spray in air, was proposed. Test results showed that the influence of swirl on combustion was quite different from that with a shallow dish chamber. The combination of promoting fuel spray diffusion and high air swirl brought reduction of smoke emissions and fuel consumption.
Diesel Combustion Improvement with High Pressure Fuel Injection - Characteristics of Diesel Sprays from Micro-Hole Nozzles - Hiroshi Yamamoto, Yoshinaka Takeda, Keiichi Niimura (New ACE
Institute Co., Ltd.) This paper presents the results of fuel spray observation and engine test on the micro-hole nozzles with high pressure fuel injection. The effects of nozzle hole diameter on fuel spray characteristics and spray overlap effects with numerous hole nozzles were investigated. In the engine test, NOx emissions were reduced through the shortening of ignition delay and high smoke emissions resulted from the spray overlap effects of numerous hole nozzles.
9539293 Combustion and Exhaust Emissions in a Glow-assisted Methanol DI Engine-Optimization of Slit Geometries and Glow-plug Temperature - Jin Kusaka, Yasuhiro Daisho, Takeshi Saito and Ry6ji Kihara (Waseda University) The glow assisted ignition system utilized in a direct-injection diesel engine fueled with methanol tends to suffer from poor ignitability and
9539329 New 2.5L in Line Turbo Diesel Engine Hiroshi Kodama, Norio Minato, Norio Miyatani, Tsuyoshi Hosomoto (Mazda Motor Corporation) We have developed new 2.5L turbo-charged diesel engine for the new Bongo Friendee. The new engine, named WLT. was designed with low emission, economy, and high-performance objectives and is the first SOHC 3-valve diesel engine in Japan. Due to the adoption of a 3-valve mechanism and other newly developed technologies, the WLT has achieved high a level combination of low emission with high performance, including low fuel consumption and quiet operation.
Development of a Lightweight and Good Fuel Economy V6 Engine for Front Engine - Rear Wheel Drive Cars Shinichi Na-
gashigi, Isao Doi, Takashi Ishizuka, Takashi Okuyama (Nissan Motor Co., Ltd.) The VQ engine mounted in the new Cedric and Gloria is a new-generation V6 DOHC engine developed by modiflying the engine of Maxima and Cefiro, which were put into the market in 1994, in order to adapt it to the front engine-rear wheel drive configuration. A turbo-charged version is also added to the VQ engine series. The features of this engine are better fuel economy, obtained by adding a variable valve to the 2-way cooling system, improved N.V.H. performance by virtue of enlarged crankshaft pin diameter and quicker engine response, by adopting a linear-charge concept and a plastic compressor impeller for the turbocharged engine. 9539347
Development of the New TD27ETi Engine for Recreational
Tadashi Sato, Shinya Obana, Yasushi (Nissan Diesel Motor Co., Ltd.)
Imai, Toshio Morotomi