Refine Your Search

Search Results

Viewing 1 to 7 of 7
Technical Paper

Development Project of a Multi-cylinder DISI Hydrogen ICE System for Heavy Duty Vehicles

The planned development of a hydrogen ICE system for trucks is one of the technological candidates for air pollution reduction and global warming prevention for the large-sized (heavy-duty) trucks supporting Japanese freightage. This project is the first to develop a DISI multi-cylinder hydrogen ICE system aimed at combining high power output and low NOx generation.
Technical Paper

Development of High Pressure H2 Gas Injectors, Capable of Injection at Large Injection Rate and High Response Using a Common-rail Type Actuating System for a 4-cylinder, 4.7-liter Total Displacement, Spark Ignition Hydrogen Engine

Key requirements of engines for vehicles are large output power and high efficiency, low emission as well as small size and light weight. Hydrogen combustion engines with direct injection have the characteristics to meet these factors. Tokyo City University, former Musashi Institute of Technology, has studied hydrogen fueled engines with direct injection since 1971. The key technology in the development of hydrogen fueled engines is the hydrogen injector for direct injection with the features such as high injection rate, high response and no hydrogen gas leakage from the needle valve of the hydrogen injector. A common-rail type system to actuate the needle valves of the high pressure hydrogen injectors was intentionally applied to fulfill good performances such as large injection rate, high response and no hydrogen gas leakage.
Technical Paper

Development of a Hydrogen Flow Sensor

A new hydrogen flow sensor was designed and evaluated based on the concept of hot wire anemometry. This sensor is designed to measure the mass flow rate of hydrogen gas used in (but not limited to) proton exchange fuel cell, PEFC. The conceptual evaluation was initiated by deriving an electro-thermal model of the hot wire required for sensing hydrogen velocity. The modeling is done via a mechatronics software tool, Saber™. This model was validated using air as a medium. Simulated and experimental performance results and safety issues are presented and discussed in this paper. Fail safe methods and effectiveness have been investigated along with hydrogen ignition temperatures with varying hydrogen to air ratio.
Technical Paper

Effect of Hydrogen Jet on Mixture Formation in a High-Pressure Injection Hydrogen Fueled Engine with Spark Ignition

In order to establish hydrogen engines for practical use, it is important to overcome difficulties caused by unique characteristics of hydrogen fuel. A hydrogen engine with direct injection right before top dead center(TDC) and spark ignition has advantages such as prevention of abnormal combustion and realization of high power output near the stoichiometric air-fuel ratio, in comparison with an engine with external mixture. On the other hand, it has been pointed out that ignition and combustion for this type of hydrogen engines should be improved and that further studies on mixture formation of air and injected hydrogen are necessary for the improvement. For the direct injection hydrogen engine, mixture is formed both by air flow inside the combustion chamber and by injected hydrogen jet.
Technical Paper

Hydrogen Fueled ICE, Successfully Overcoming Challenges through High Pressure Direct Injection Technologies: 40 Years of Japanese Hydrogen ICE Research and Development

After some 40 years of practical research and testing in Japan, the technology for a high pressure direct injection hydrogen internal combustion engine (ICE) with near-zero emissions free from CO2 was successfully developed by the author. Four fundamental challenges to make a hydrogen car a competitive alternative to both electric and traditional fossil fuel vehicles were successfully met. (1) Hydrogen’s lack of lubrication destroys the sealing surface of the injector nozzle. (2) Injectors must be of very small size to be installed onto the engine head where the four valves are located on each cylinder. (3) Multi-injection requires high dynamic response. (4) Liquid hydrogen tank’s internal pump would fail when bringing liquid hydrogen (LH2) to the required high pressure levels due to frictional heat.
Technical Paper

Low NOx Emission Automobile Liquid Hydrogen Engine by Means of Dual Mixture Formation

According to authors' previous research, high pressure hydrogen engines with direct injection right before TDC and spark ignition obtain high performance and eliminate almost. abnormal combustion. This study has clarified the mooted points in the flame propagation to adjacent jets and the control of the optimum spark timing and large NOx emissions even in leaner than excess air ratio of λ=2. Nitric oxides (NOx) is the only the pollutant in the exhaust gases emitted by hydrogen engines. It has been found that the NOx formation largely depends on the mixture formation method. In order to operate the engine in a small amount of NOx, an experimental study was carried out to investigate the reduction of NOx and the output power by using dual mixture formation method, external mixture formation and direct injection.
Journal Article

Summary and Progress of the Hydrogen ICE Truck Development Project

A development project for a hydrogen internal combustion engine (ICE) system for trucks supporting Japanese freightage has been promoted as a candidate for use in future vehicles that meet ultra-low emission and anti-global warming targets. This project aims to develop a hydrogen ICE truck that can handle the same freight as existing trucks. The core development technologies for this project are a direct-injection (DI) hydrogen ICE system and a liquid hydrogen tank system which has a liquid hydrogen pump built-in. In the first phase of the project, efforts were made to develop the DI hydrogen ICE system. Over the past three years, the following results have been obtained: A high-pressure hydrogen gas direct injector developed for this project was applied to a single-cylinder hydrogen ICE and the indicated mean effective pressure (IMEP) corresponding to a power output of 147 kW in a 6-cylinder hydrogen ICE was confirmed.