TY - JOUR
T1 - A shock-tube investigation of the dynamics of gas-particle mixtures
T2 - Implications for explosive volcanic eruptions
AU - Chojnicki, K.
AU - Clarke, Amanda
AU - Phillips, J. C.
PY - 2006/8
Y1 - 2006/8
N2 - [1] We use 1-D shock-tube experiments to investigate the dynamics of rapidly-decompressed gas-particle mixtures and associated shock waves, with application to the initial stages of Vulcanian and Plinian eruptions. For particle sizes 45-150 μm and pressure ratios 1-70, experimental particle Reynolds numbers reach 104 and impulsive accelerations reach 150 g. The experiments suggest that particles hinder gas motion via an interphase drag force, reducing shock strength and velocity. Gas-particle mixture velocities decrease with increasing particle diameter for a given initial pressure ratio and are less than those predicted by pseudogas approximations and existing interphase drag relationships due to imperfect phase coupling and unsteady flow during high-acceleration stages. We present a new analysis for predicting shock strength and velocity for gas-particle mixtures, and apply our improved interphase drag terms to the high-acceleration, eruption initiation stage of Vulcanian eruptions
AB - [1] We use 1-D shock-tube experiments to investigate the dynamics of rapidly-decompressed gas-particle mixtures and associated shock waves, with application to the initial stages of Vulcanian and Plinian eruptions. For particle sizes 45-150 μm and pressure ratios 1-70, experimental particle Reynolds numbers reach 104 and impulsive accelerations reach 150 g. The experiments suggest that particles hinder gas motion via an interphase drag force, reducing shock strength and velocity. Gas-particle mixture velocities decrease with increasing particle diameter for a given initial pressure ratio and are less than those predicted by pseudogas approximations and existing interphase drag relationships due to imperfect phase coupling and unsteady flow during high-acceleration stages. We present a new analysis for predicting shock strength and velocity for gas-particle mixtures, and apply our improved interphase drag terms to the high-acceleration, eruption initiation stage of Vulcanian eruptions
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U2 - 10.1029/2006GL026414
DO - 10.1029/2006GL026414
M3 - Article
AN - SCOPUS:33845658143
SN - 0094-8276
VL - 33
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 15
M1 - L15309
ER -