Modular engine units including turbine engine with combustion mediating hub

An engine comprising:

• an engine housing;
• a drive shaft mounted within the engine housing;
• a first impeller mounted on the drive shaft for movement therewith and having vanes inclined in a first direction relative to a rotational axis of the driveshaft;
• a second impeller mounted on the drive shaft for movement therewith and having vanes inclined in the first direction relative to the rotational axis of the driveshaft;
• a combustion mediating hub located between the second impeller and the first impeller and mounted on the drive shaft with a bearing for freely rotatable movement in both the first direction and a second direction about the drive shaft, the combustion mediating hub including an annular plate having a first surface, a second surface opposing the first surface, and an outer peripheral wall extending between the first surface and the second surface, the annular plate including an inner portion adjacent to the bearing and an outer portion adjacent to the outer peripheral wall, a first plurality of blades mounted on the first surface of the annular plate on at least the outer portion of the annular plate and extending axially toward the second impeller and a second plurality of blades mounted on the second surface of the annular plate on at least the outer portion of the annular plate and extending axially toward the first impeller, the first plurality of blades and the second plurality of blades inclined in the second direction;
• an ignition source extending through the engine housing into an area between the outer peripheral wall of the annular plate and an inner wall of the engine housing;
• and
• a fuel source extending through the engine housing into the area between the outer peripheral wall of the annular plate and the inner wall of the engine housing.