EJECTOR COOLING OF OUTER CASE FOR TIP TURBINE ENGINE

摘要

A tip turbine engine (10) includes a combustor (30) radially outward of a fan. In order to reduce the heat transfer from the combustor and the high-energy gas stream generated by the combustor, a cold air ejector (38) radially outward of the combustor extends from a forward end of the nacelle (12) to a point rearward of the combustor and an exhaust mixer (110). The cold air ejector includes an annular inlet (17) at the forward end of the nacelle. The cold air ejector draws air over the outer engine case (39) to provide a boundary between the nacelle and the hot outer engine case. The layer of air being pulled past the engine case ejects the heat, thereby preventing the heat from escaping into the nacelle or engine bay.