AIRCRAFT ICING

Abstract

▪ Abstract Full-scale icing experiments and, therefore, certification time and cost can be significantly reduced by developing calculation methods to evaluate the aircraft and system performance for a wide range of icing conditions. This article summarizes calculation methods for icing that include ice accretion, ice system performance, and icing effects on aircraft.

Computational Methodology for Bleed Air Ice Protection System Parametric Analysis

“…A quantitative method for assessing the agreement between experimental and calculated ice shapes can be found at [19,20,21]. [4].…”

“…Federal Aviation Administration (FAA), according to its Federal Airworthiness Regulations (FAR) Part 25, classifies the particles in suspension as [3]: The forward facing surfaces of airplanes are the most susceptible to impact with suspended droplets, specially the leading edges (LE) of engine inlets, tail planes, wings, rotors, and instrumentation probes [4,5]. Ice accreted on the airframe can shed and be ingested by rearmounted engines, damaging compressor blades and even causing combustors to flame-out.…”

IR thermography in heat transfer measurements on a wing leading edge surface internally impinged by a row of air jets

“…As already said, heat transfer measurements are performed owing to the heated thin foil sensor for which the convective heat transfer coefficient h is given by the following relationship: (1) where is the Joule heating per unit area, is thermal radiation heat flux, is natural convection heat flux and is the foil lateral thermal conduction heat flux. T w and T aw are wall and adiabatic wall temperatures that are measured on the foil surface opposite to jets impingement (see Fig.1); (i.e., jets impinge internally on the leading edge while the infrared camera views the external surface).…”

“…Then, the ice formation and accretion is receiving great interest [1] and several methods of ice prevention and removal have been designed. In particular, ice formation on wings and engine inlets of modern commercial transport aircraft can be prevented by extracting hot air from the compressor and blowing it on the inside surface of the leading edge through small holes drilled in a pipe [2] in order to supply enough energy to evaporate the impinging water or to maintain the surface at a temperature above the freezing value.…”

PoliMIce: A simulation framework for three-dimensional ice accretion

“…The icing phenomenon affects aircraft flying in severe conditions, like those that can be encountered in clouds composed by super-cooled droplets, namely, droplets in a state of unstable thermo-mechanical equilibrium that is possibly perturbed upon impact on the surface, generating water freezing [8].…”