Question: Consider again Prob., but let the aircraft speed be 300 m/s. At what airspeed does direct cooling become impossible?
Problem: An aircraft oil cooler is to be constructed using the skin of the wing as the cooling surface. The wing may be idealized as a flat plate over which air at 71 kPa and -4°C flows at 61 m/s. The leading edge of the cooler may be located 0.9 m from the leading edge of the wing. The oil temperature and oil-side heat-transfer resistance are such that the surface can be at approximately 54°C, uniform over the surface. How much heat can be dissipated if the cooler surface measures 60 cm by 60 ern? Would there be any substantial advantage in changing the shape to a rectangle 1.2 m wide by 0.3 m in flow length?