Unducted fan has no duct around the fan, such as the CFM Rise engine. You must have been referring to combined exhaust (also known as a mixed exhaust) such as the we saw on the 727 and we see on the A330-300 with the Rolls Royce Trent 700 engine, and a separate exhaust as we see on most turbofan engines. Unducted fans have the fan blades open to the air.
Thank you so much for clarifying so many topics on jet engines’ inlet and outlets!
Unducted fan has no duct around the fan, such as the CFM Rise engine. You must have been referring to combined exhaust (also known as a mixed exhaust) such as the we saw on the 727 and we see on the A330-300 with the Rolls Royce Trent 700 engine, and a separate exhaust as we see on most turbofan engines. Unducted fans have the fan blades open to the air.