thumbnail

Investigating the accuracy of one‐dimensional volcanic plume models using laboratory experiments and field data

Journal of Volcanology and Geothermal Research
By: , , , and 
https://doi.org/10.1029/2018jb017224

Links

Abstract

During volcanic eruptions, model predictions of plume height are limited by the accuracy of entrainment coefficients used in many plume models. Typically, two parameters are used, α and β, which relate the entrained air speed to the jet speed in the axial and cross‐flow directions, respectively. To improve estimates of these parameters, wind tunnel experiments have been conducted for a range of cross‐wind velocities and turbulence conditions. Measurements are compared directly to computations from the 1‐D plume model, Plumeria, in the near‐field, bending region of the jet. Entrainment coefficients are determined through regression analysis, demonstrating optimal combinations of effective α and β values. For turbulent conditions, all wind speeds overlapped at a single combination, α = 0.06 and β=0.46, each of which are slightly reduced from standard values. Refined coefficients were used to model plume heights for 20 historical eruptions. Model accuracy improves modestly in most cases, agreeing to within 3 km with observed plume heights. For weak eruptions, uncertainty in field measurements can outweigh the effects of these refinements, illustrating the challenge of applying plume models in practice.

Publication type Article
Publication Subtype Journal Article
Title Investigating the accuracy of one‐dimensional volcanic plume models using laboratory experiments and field data
Series title Journal of Volcanology and Geothermal Research
DOI 10.1029/2018jb017224
Volume 124
Issue 11
Year Published 2019
Language English
Publisher American Geophysical Union
Contributing office(s) Volcano Science Center
Description 15 p.
First page 11290
Last page 11304
Google Analytic Metrics Metrics page
Additional publication details