TY - GEN
T1 - Jet erosion test apparatus
T2 - International Conference on Fluvial Hydraulics, RIVER FLOW 2016
AU - Liu, Xiaofeng
AU - Farthing, Matthew W.
AU - Talepour, Mahdad
N1 - Publisher Copyright:
© 2016 Taylor & Francis Group, London.
PY - 2016
Y1 - 2016
N2 - Estimation of sediment erodibility is often required for the evaluation of channel migration, local scour around hydraulic structures, levee stability, etc. Among many erodibility test methods, the constant velocity jet erosion test apparatus is widely used. The premise of this method is the theory of jet flow impinging on a plane surface and the associated wall shear stress. However, in a jet erosion test, the sediment is gradually removed and a scour hole develops as a function of time. As a result, the impinging surface is not planar. In addition, the cylindrical confinement of the jet flow, instead of unbounded in the theory, makes the wall shear estimation departing from the jet theory. This paper uses a 3D computational model to appraise the above effects and quantify the errors by using the theoretical formulas. The computational model is validated by experimental data where PIV measurements were taken in a box without the sediment sample. The use of box is for better illumination of laser sheet of PIV. In another experiment, the sediment sample was placed in the JET apparatus and the scoured bed was scanned at time 0, 8, and 200 minutes. The scanned surfaces of the scour holes are used in the computational model to simulate the flow field at the corresponding moments. It is found that the computational model predicts the flow filed well in the box experiment. Further, the model allows a detailed analysis of the velocity, turbulence intensity, Reynolds stress, etc, in JET apparatus.
AB - Estimation of sediment erodibility is often required for the evaluation of channel migration, local scour around hydraulic structures, levee stability, etc. Among many erodibility test methods, the constant velocity jet erosion test apparatus is widely used. The premise of this method is the theory of jet flow impinging on a plane surface and the associated wall shear stress. However, in a jet erosion test, the sediment is gradually removed and a scour hole develops as a function of time. As a result, the impinging surface is not planar. In addition, the cylindrical confinement of the jet flow, instead of unbounded in the theory, makes the wall shear estimation departing from the jet theory. This paper uses a 3D computational model to appraise the above effects and quantify the errors by using the theoretical formulas. The computational model is validated by experimental data where PIV measurements were taken in a box without the sediment sample. The use of box is for better illumination of laser sheet of PIV. In another experiment, the sediment sample was placed in the JET apparatus and the scoured bed was scanned at time 0, 8, and 200 minutes. The scanned surfaces of the scour holes are used in the computational model to simulate the flow field at the corresponding moments. It is found that the computational model predicts the flow filed well in the box experiment. Further, the model allows a detailed analysis of the velocity, turbulence intensity, Reynolds stress, etc, in JET apparatus.
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U2 - 10.1201/9781315644479-215
DO - 10.1201/9781315644479-215
M3 - Conference contribution
AN - SCOPUS:85015340187
SN - 9781138029132
T3 - River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016
SP - 1360
EP - 1363
BT - River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016
A2 - Constantinescu, George
A2 - Garcia, Marcelo
A2 - Hanes, Dan
PB - CRC Press/Balkema
Y2 - 11 July 2016 through 14 July 2016
ER -