Critical impact velocity for ice fragmentation

Abstract

The fragmentation process is a main concern in many engineering applications such as preventing flameouts of aircraft engines. The authors of this article are interested in measuring the critical impact velocity for ice fragmentation. Precisely, a dropweight technique was applied to study the ice ball impacts on glass plates. The influence of ice ball temperature, diameter and impact angle is also investigated. The after-impact ice ball state was found to be classified into two cases: an altered state and a non-altered state. The critical impact velocity is defined as the minimum impact velocity for which the ice ball is altered after impact or the maximum impact velocity for which the ice ball is not altered after impact. The experimental results are analysed by a model, assuming that the alteration regime is observed as soon as the ice ball normal kinetic energy is higher than a critical value of its deformation energy. This model depends on one parameter which is determined in this study. This last result is the major achievement of this article as there is almost no measurement of this parameter in the literature.

Glaciated and mixed phase ice accretion modeling using ONERA 2D icing suite

“…According to experimental observations, the onset between the bouncing and the shattering regimes strongly depends on the particle normal kinetic energy before the impact 31,33 . To account for this experimental fact, the following dimensionless number was introduced by Vidaure and Hallet 33 for ice crystals and by Guégan et al for hail particles 28 . It corresponds to the ratio of the normal kinetic energy to the surface energy (assuming a spherical shape for the particle).…”

Eulerian method for ice crystal icing in turbofan engines

“…Vidaurre and Hallett [136] assumed the reference surface energy e σ0 to be 0.12 J/m 2 at T 0 = 253 K. Higa et al [55] stated that the activation energy Q s is equal to 48.2 kJ/mol. Impact experiments of Higa et al [55], Vidaurre and Hallett [136], Guégan et al [47] and more recently from Hauk et al [51,52] confirm that two critical values of L can be defined that identify three possible impact regimes:…”

“…In the inelastic regime the restitution coefficient decreased with increasing impact velocity and with increasing particle size. Guégan et al [47,48] • ) were tested for a range of velocities between 60 and 200 m/s. The experiments have shown that the post-impact particles are emitted in a circular cloud.…”

Numerical simulation of ice accretion under mixed-phase conditions

“…When ice crystals impinge on a dry surface, disintegration and rebounding may occur. Gue´gan et al 19 studied the critical velocity of an ice ball breakup and derived the experimental relation as follows…”