EXPERIMENTAL STUDY OF IMPINGEMENT HEAT TRANSFER CHARACTERISTICS IN A CONVERGENT CHANNEL WITH PIN FIN

The protection of the inlet components of an aircraft engine from the adverse effects of ice accretion has been a crucial design problem since the very early years of flight. Therefore, the configuration with efficient heat transfer is the focus on the design of a hot-air anti-icing system in an aeroengine. This paper studies experimentally on the heat transfer in a convergent channel with pin fin within the strut. Experiments are carried out by using a transient liquid crystal technique. The dimensionless lateral distance (S/d, where S is the distance between the leading edge and pin fin, d is the diameter of the impingement hole), the dimensionless vertical distance (S1/d, where S1 is the distance between pin fins) as well as the pitch ratio (D/d, where D is the diameter of the pin fin) of the pin fin and impingement hole are respectively investigated to study the heat transfer on the surface of convergent channel. The Reynolds number based on the hydraulic diameter of the impingement hole ranges from 6300 to 12700. Within the experimental range, the result shows that the Average Nusselt Number increases at first and then decreases as the dimensionless lateral distance S/d increases. The Average Nusselt Number has the highest value when S/d=2.5;When the dimensionless vertical distance S1/d increases, the Average Nusselt Number goes up at first and then reduces.The Average Nusselt Number has the highest value when S1/d=3;The increasing pitch ratio D/d leads to a lower Average Nusselt Number. The Average Nusselt Number has the highest value when D/d=1/3.;The Average Nusselt Number increases as the Reynolds number increases.