ISSN Online: 2377-424X
ISBN Print: 978-1-56700-421-2
International Heat Transfer Conference 15
Study of the Flow and Heat Transfer of Water Film on Hot Air Anti-Icing Airfoil Surface
Abstract
Ice accretion on aircraft surfaces usually causes degradation of aircraft performance and operation safety.
Many efforts have been made to simulate ice shape on aircraft surfaces. It is important to obtain accurate
results of the impingement properties of water droplets and the heat and mass transfer on the aircraft surface
to predict the ice shape. A layer of water film will be formed on the leading edge of airfoil when water
droplets impinge on these components. The physical behavior of water film flow and related heat and mass
transfer under icing conditions are very complex. Modeling the water film runback and evaporation is the
purpose of this paper. A numerical method is presented to predict the water film flow and the heat and mass
transfer on the anti-icing surface. A computational model considering the surface water runback, convection
and conduction heat transfer, the heat and mass transfer associated with the water evaporation is developed.
The heat and mass transfer of surface water flow is studied by solving the integral equations of water film.
The effect of liquid water content (LWC) and temperature of wall surface is analyzed. The range of LWC is
from 0.5 g/m3 to 2.0 g/ m3 and the surface temperature changes from 10 °C to 40 °C. The results show that the water film thickness on the airfoil surface is reach to 25 μm and most anti-icing energy is exhausted by evaporation and convection. It also shows that the heat loss caused by evaporation is sensitive to the wall
temperature. Energy required underthe wet surface anti-icing condition is also analyzed.