Hello Mr. Alvaro.
The best material for printing this air duct will be ASA:
Filament Properties:
Strength. High.
Flexibility. Medium.
Durability. High.
Difficulty to Use. Medium.
Print Temperature. 240°C – 250°C.
Print Bed Temperature. 100°C – 125°C.
Bed Adhesion. Hair Spray or ABS Glue.
Soluble. In esters, ketones, and acetone.
It easily withstands temperatures up to 100 degrees Celsius and is durable.
It is best to set printer to 80-90% density to increase durability.
You can also use PEA12 + CF - filament with carbon fibers. It withstands temperatures up to 160 degrees Celsius, is very durable, but wears out the printer a lot and is expensive. The surface after printing is very rough to the touch.
Rather for printing elements that must be very durable.
I would print these air ducts using ASA.