Japanese automakers dream of the ultimate gas-powered engine

Leaders of the Research Association of Automotive Internal Combustion Engines (AICE) meet the press on May 19 in Tokyo.

TOKYO -- Japanese automakers are renewing efforts to develop a dream version of a gas-powered engine unlike any out there.
     Engineers at Mazda Motor are racing to develop an ideal fuel-efficient engine that could exceed 40 kilometers per litter for a purely gas-powered car, and 50km for a hybrid.
     Their current research subject is the homogeneous charge compression ignition (HCCI). The technology has been touted as an ultimate fuel technology because it is expected to significantly improve fuel efficiency and also produce far less nitrogen oxide.
     It works by injecting an air-gasoline vapor mix into an engine, which raises the temperature by compressing the vapor with a piston, which causes self-ignition.
     However, due to difficulties in controlling the technology, no automaker has ever brought it to practical use. It is still some time off, but Mazda is aiming to make a car that is powered with this ideal engine by 2020, the year the Olympics will be held in Tokyo. To do this, Mazda researchers are looking to computer simulations for help.
There's always more
There are critics out there that say the internal combustion engine is already outdated. But Mitsuo Hitomi, managing executive officer in charge of R&D at Mazda, said there remains much room for improvement still, even though it has been the subject of study for a long time.
     There are mounting reasons of late to reinvent the engine. Automakers know that 90% of cars around the world are still powered by gas engines.
     Scientists at Honda Motor are working on developing a technology called Homogeneous Lean Charge Spark Ignition (HLSI). The technology uses the same approach as HCCI in that it mixes air and fuel before it is injected into the engine. The difference is that the technology does not use a self-ignition system but controls combustion with a spark plug, just like conventional engines.
     The fundamental efficiency of HLSI engines looks to be lower than that of HCCI. However, Michio Shinohara, general manager of Honda's Environment & Safety Planning Office, said that it might be possible to improve HLSI so that it can outperform HCCI engines.
     Meanwhile, European carmakers are focusing on technologies that could improve fuel efficiency by combining a small displacement engine with a turbocharger.
     With all these developments, consumers could soon be faced with the choice of buying cars powered by hybrid engines, electric engines and ultra-efficient gasoline engines. However, an official at a major automaker said the development of an ultimate gas engine is stretching the resources of auto companies, including their engineers, due to the increasingly complex nature of the task.
     To help this along, there is the industry-academia-governmental partnership -- the Research Association of Automotive Internal Combustion Engines (AICE).
Better together
On April 1, eight Japanese automakers and one automobile research institute jointly set up the AICE. Its main goal is to help Japanese carmakers better compete with European rivals, who are seen as being better at conducting successful basic research.
     A research team led by Jin Kusaka, professor of engineering at Waseda University, aims to establish in the next two years a simulation technology that can assess the effectiveness and other performance variables of filters that clean exhaust gas used for diesel engines. If the team could make the technology commercially viable, automotive engineers could make fewer filter prototypes, slashing the time required for development.
     Engineers at Toyota Motor are also expected to participate in the project. The automakers are to jointly share their research findings. Keiji Otsu, president of the AICE, said the entity hopes to strengthen development infrastructure of the Japanese automotive industry.