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This content will become publicly available on April 26, 2019

Title: A new method to calculate unsteady particle kinematics and drag coefficient in a subsonic post-shock flow

In this paper, we introduce a new method (piecewise integrated dynamics equation fit, PIDEF) that uses the particle dynamics equation to determine unsteady kinematics and drag coefficient (C D) for a particle in subsonic post-shock flow. The uncertainty of this method is assessed based on simulated trajectories for both quasi-steady and unsteady flow conditions. Traditional piecewise polynomial fitting (PPF) shows high sensitivity to measurement error and the function used to describe C D, creating high levels of relative error (>>1) when applied to unsteady shock-accelerated flows. The PIDEF method provides reduced uncertainty in calculations of unsteady acceleration and drag coefficient for both quasi-steady and unsteady flows. This makes PIDEF a preferable method over PPF for complex flows where the temporal response of C D is unknown. Finally, we apply PIDEF to experimental measurements of particle trajectories from 8-pulse particle tracking and determine the effect of incident Mach number on relaxation kinematics and drag coefficient of micron-sized particles.
ORCiD logo [1] ; ORCiD logo [2] ;  [1] ;  [1] ;  [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Arizona State Univ., Tempe, AZ (United States). School for Engineering of Matter, Transport and Energy
Publication Date:
Report Number(s):
Journal ID: ISSN 0957-0233
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Measurement Science and Technology
Additional Journal Information:
Journal Volume: 29; Journal Issue: 7; Journal ID: ISSN 0957-0233
IOP Publishing
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; particle tracking accelerometry; kinematics measurement; shock-particle interaction; unsteady drag
OSTI Identifier: