Experimental and Computer Model Results for a Bleed Air Ice Protection System

Results from a two-dimensional computer model developed at Wichita State University (WSU) for bleed air system analysis are compared with experimental data from icing tunnel tests performed with a wing model equipped with a hot air ice protection system. The computer model combines a commercial Navier-Stokes flow solver with a steady-state thermodynamic analysis model that applies internal flow heat transfer correlations to compute wing leading edge skin temperatures and the location and extent of the runback ice. The icing tunnel data used in the validation of the computer model were obtained at the NASA Icing Research Tunnel using representative in-flight icing conditions and a range of bleed air system mass flows and hot air temperatures. Correlation between experiment and analysis was good for most of the test cases used to assess the performance of the simulation model. A study was also conducted with the computer model developed to evaluate the accuracy of a methodology for scaling in-flight icing and external flow conditions to accurately reproduce the performance of bleed air ice protection systems in ground-based icing facilities. In general, the results of the scaling study demonstrated good correlation in leading edge temperature distributions and runback ice shape locations between the scaled and reference (full-scale) flight conditions.