This paper presents an experimental research for studying the relative and interactive effects of three physicochemical fluid characteristics (viscosity, pH, and ionic strength) on the incipient motion of a granular particle under laminar flow condition. Critical flow velocity for particle's incipient motion, an important factor for evaluating flow-induced soil erosion, was used to quantify the relative erosive capacity of the test fluids. Response surface methodology (RSM), a statistical design of experiments, was used to design and implement 20 test fluids with various levels of the three fluid characteristics. Incipient motion of a highly spherical glass bead positioned atop a specially designed and manufactured support pocket within an enclosed flow cell was observed using a microscope video camera. The critical flow velocity was quantified for seven repeat trials for each of the 20 test fluids. Regression analyses were conducted on the results to generate a statistical model to describe the relative effects of the three factors and their interactions. The main findings include: (1) viscosity, pH, and their two-way interaction were determined to be the most influencing factors on critical velocity; (2) the effects of the three fluid characteristics on critical velocity follow the following decreasing order: viscosity, pH, and ionic strength; (3) viscosity and pH were both shown to have an inverse relationship with critical velocity; and (4) at higher pH (such as 10.5), the viscosity has greater influence on critical velocity than at a lower pH (such as 3.5).
|Original language||English (US)|
|Journal||Journal of Hydraulic Engineering|
|State||Published - May 1 2018|
All Science Journal Classification (ASJC) codes
- Civil and Structural Engineering
- Water Science and Technology
- Mechanical Engineering