Modelling the growth of large rime ice accretions

Lasse Makkonen; Zhang Jian; Timo Karlsson; Mikko Tiihonen

doi:10.1016/j.coldregions.2018.03.014

Modelling the growth of large rime ice accretions

Lasse Makkonen, Zhang Jian, Timo Karlsson, Mikko Tiihonen

Research output: Contribution to journal › Article › Scientific › peer-review

4 Citations (Scopus)

Abstract

The conventional theory of droplet collision with an object can be used only down to a collision efficiency of about 0.1. Therefore, no accurate modelling of in-cloud icing has been possible when droplets are small, wind speed is low, or the object is large. This has also put a limit on the size of an ice accretion on e.g. a power line cable up to which its growth can be simulated. We utilize results of icing wind tunnel experiments and fluid dynamics simulations to explain the differences between the experiments and the theory when the collision efficiency is small. We confirm that the history term in the droplet trajectory equations becomes relevant at small collision efficiencies. Including this term, and applying the integral over the size distribution instead of using themedian volume diameter, shows that accurate modelling of icing at very small collision efficiencies is feasible. This makes it possible to estimate large rime ice loads relevant to structural design.

Original language	English
Pages (from-to)	133-137
Journal	Cold Regions Science and Technology
Volume	151
DOIs	https://doi.org/10.1016/j.coldregions.2018.03.014
Publication status	Published - Jul 2018
MoE publication type	A1 Journal article-refereed

Fingerprint

rime

Ice

collision

accretion

ice

droplet

modeling

Fluid dynamics

power line

Structural design

Wind tunnels

fluid dynamics

Cables

wind tunnel

cable

Experiments

Trajectories

experiment

wind velocity

trajectory

Keywords

ice accretion
rime ice
collision efficiency
history term
droplet distribution

Cite this

Makkonen, L., Jian, Z., Karlsson, T., & Tiihonen, M. (2018). Modelling the growth of large rime ice accretions. Cold Regions Science and Technology, 151, 133-137. https://doi.org/10.1016/j.coldregions.2018.03.014

Makkonen, Lasse ; Jian, Zhang ; Karlsson, Timo ; Tiihonen, Mikko. / Modelling the growth of large rime ice accretions. In: Cold Regions Science and Technology. 2018 ; Vol. 151. pp. 133-137.

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Makkonen, L, Jian, Z, Karlsson, T & Tiihonen, M 2018, 'Modelling the growth of large rime ice accretions', Cold Regions Science and Technology, vol. 151, pp. 133-137. https://doi.org/10.1016/j.coldregions.2018.03.014

Modelling the growth of large rime ice accretions. / Makkonen, Lasse; Jian, Zhang; Karlsson, Timo ; Tiihonen, Mikko.

In: Cold Regions Science and Technology, Vol. 151, 07.2018, p. 133-137.

Research output: Contribution to journal › Article › Scientific › peer-review

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