plug is one of the key components of an internal combustion engine and for the
history of the internal combustion engine. The lowly spark plug is the key
component that allows the fuel and air mixture to ignite giving us power to
burn rubber, mow lawns, blast through the water at high rates of speed.
The spark plug's days are numbered though thanks to a new
breakthrough from some scientists that have found a way to replace the
spark with a laser inside the internal combustion engine. According to
researchers, the move to lasers from spark plugs will allow cleaner and more
efficient vehicles and with the looming increases in mandated fuel economy, the
auto industry will need all the help it can get.
Lasers have historically been too large to fit under the hood of a car to be
used as ignition sources. Japanese researchers have developed a small multi-beam
laser that would be small enough to screw into a cars cylinder head. Just as
important as the size being small enough to fit under the hood is the fact that
the laser system developed is made from ceramics and can be produced cheaply
enough that it can be sold in volume for vehicle use.
The way a laser ignition source would be able to make engines more efficient is
by allowing the engines to run leaner, thereby requiring less fuel and
producing fewer harmful emissions. The leaner and engine is able the run, the
more power it is able to produce as well. That would mean that a laser ignition
source could be a great thing for automotive enthusiasts.
Takunori Taira from the Japan National Institutes of Natural Sciences says that
the laser beam can also be made to focus into the exact center of the air/fuel
mixture. That would allow the explosion inside the combustion chamber to spread
the resulting flame in a more efficient manner since it would not be quenched
by the surrounding cold metal of the cylinder walls just as it explodes.
He said, "Timing -- quick combustion -- is very important. The more
precise the timing, the more efficient the combustion and the better the fuel
The researchers say that to ignite the fuel mixture the laser has to focus 100
gigawatts per square centimeter square with short pulses of more than 10
millijoules each measures in Hz. "In the past, lasers that could meet
those requirements were limited to basic research because they were big,
inefficient, and unstable." The researchers have created a laser that can
meet the requirements using ceramics.
commercial automotive engine will require pulses of 60Hz to ignite the fuel and
the team is testing lasers at 100Hz.