Lighter/simpler turbo pump

I have been wondering about a turbo pump that consists of a rotary
sprinkler come Catherine wheel physically situated within the combustion
chamber. This should not inhibit regenerative cooling. It is integral,
self cooling, should improve mixing and combustion, requires no
secondary combustion or gas generation and is much much lighter. In
essence it is just a fancy self powering injector.

Thoughts? Has this been done before?

Pete.