Abstract
ABSTRACTVertical velocity distribution in some fluid–solid flows such as debris flows has not been well recognized and lacked a commonly accepted form. The particle image velocimetry (PIV) measurement system was employed to investigate the velocity distribution of high-viscosity fluid–solid flows. The velocity distribution was greatly affected by the particles due to the particle-particle collision and momentum exchange between the particle and fluid. Both of them show a similar increasing trend only in the range of the dimensionless flow depth from 0 to 0.7. In addition, based on the log-law model for sediment-laden flows, a modified model was proposed to predict vertical velocity distribution in debris flows. The results indicated that the calculated results were in good agreement with the experimental ones. The coefficient and index for the modified item was about 0.92 and −1/6, respectively.
Highlights
Debris-flow velocity distribution form is one of the most complex problems in the dynamic mechanism of this kind of solid-fluid mixture flow due to the flow’s opacity caused by its high concentration of solid particles (Han et al 2014)
The velocity distribution through the flow depth was analyzed based on the experimental results
Experiments were carried out to investigate the instantaneous velocity field of debris flow based on the particle image velocimetry (PIV) measurement technique
Summary
Debris-flow velocity distribution form is one of the most complex problems in the dynamic mechanism of this kind of solid-fluid mixture flow due to the flow’s opacity caused by its high concentration of solid particles (Han et al 2014). In order to better understand the behavior of debris flows, different measurement methods were employed to obtain debris flow velocity. The measurement devices such as ultrasonic sensors, radar, or seismic sensors were introduced to monitor the debrisflow velocity (Arattano 2003; Hu€rlimann 2003; McArdell et al 2003; Arattano and Marchi 2005; Prochaska et al 2008; Wei et al 2012). Numerical simulation methods were employed to investigate velocity of the flow fronts, sediment entrainment from the erodible bed, transportation process based on the depth-averaged motion equations (Joode and van Steijn 2003; Mangeney et al 2007; Armanini et al 2009; Hungr and McDougall 2009; Luna et al 2012; Han et al 2015; Han et al 2016; Wang et al 2016). The impact forces at different flow depths were obtained by the impact force sensors to investigate internal velocity distribution along flow depth in an indirect way (Yang et al 2011)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
