US Patent 9194297 Multiple circuit fuel manifold

Provided is a fuel manifold with more than one fuel circuit for connecting a fuel source or fuel sources to at least one fuel injector, the fuel manifold having an inner tube for conveying fuel through a first fuel passage formed interiorly of the inner tube and an outer tube forming with a slot along a length of the inner tube a second fuel passage. If one of the fuel passages is in a low flow or no flow condition, fuel flowing through the other of the fuel passages acts to cool the fuel passage in the low flow or no flow condition to prevent stagnant fuel in the passage from heating up and coking.