Hydrogen detonation engine
The purpose of the detonation concept is to increase air pressure inside combustion chambers, which manufacturers of typical combustion engines would like to do (except that it is too impractical).
A detonation engine utilizes shock waves to achieve the desired pressure increase, which can be up to 10 times more than that of conventional combustion engines.
The most highly developed form of detonation engine, which has been in the works for many years, is the pulse detonation engine, the type GE is developing. Whereas combustion occurs continuously in a conventional jet engine, pulse detonation involves setting off a series of detonations—say, 60 to 100 per minute.
Ref: Technology review
Long E-Z aircraft with test detonation engine 2008