Inlet effects on roll-wave development in shallow turbulent open-channel flows

Rok, strany: 2016, 45 - 55

The present work investigates the effect of the flow profile induced by an inlet condition on the roll-wave evolution in turbulent clear-water flows. The study employs theoretical and numerical analyses. Firstly, the influence of the inlet condition on the spatial evolution of a single perturbation in a hypercritical flow is examined through the expansion near a wavefront analysis. The results show that an accelerated unperturbed profile reduces the disturbance spatial growth. A decelerated profile causes an increase. The effect of the flow profile on the spatial evolution of rollwave trains is then numerically investigated solving the Saint Venant equations with a second-order Runge-Kutta Total Variation Diminishing (TVD) Finite Volume scheme. The numerical simulations comply with the analytical results for the initial and transition phases of the roll-wave development. The unperturbed profile influences even the roll-waves statistical characteristics in the final stage, with a more evident effect in case of accelerated profiles. The influence of the flow profile should be therefore accounted for in the formulation of predictive criteria for roll-waves appearance based on the estimation of the disturbance spatial growth rate.

ISO 690:

Campomaggiore, F., Di Cristo, C., Iervolino, M., Vacca, A. 2016. Inlet effects on roll-wave development in shallow turbulent open-channel flows. In Journal of Hydrology and Hydromechanics, vol. 64, no.1, pp. 45-55. 0042-790X (until 2019) .

APA:

Campomaggiore, F., Di Cristo, C., Iervolino, M., Vacca, A. (2016). Inlet effects on roll-wave development in shallow turbulent open-channel flows. Journal of Hydrology and Hydromechanics, 64(1), 45-55. 0042-790X (until 2019) .