The arrested front facility consists of two separate components: a dense water (normally saline) component and a clear water component. The saline portion of the system consists of a 4000 liter reservoir (mixing tank), a constant head tank with overflow back to the mixing reservoir, and a slot valve to introduce the dense flow along the bottom of the test channel.
The clear water segment begins in a 4000 liter tailwater box. Water is pumped via 8-cm pipe to the headbox where it passes through a series of flow straighteners and turbulence dampers before entering the 3.2-m long, 30-cm wide, 50-cm deep test channel. A 1.5-m section of the test channel bottom consists of a variable speed conveyor belt (with a maximum speed of 25 cm/s). The purpose of the conveyor belt is to resist the dense underflow, resulting in the density current front to become stationary for observation. The clear water in the main channel passes over an adjustable height weir and passes back into the tailwater box for recirculation.
This facility has been used extensively to examine the mixing dynamics at the front of density driven flows1, 2, 3, 4.
1 Parsons, J.D. and Marcelo García. 1995 September. “Flow Structure and Mixing Characteristics in Saline Gravity Current Fronts.” University of Illinois at Urbana-Champaign. Civil Engineering Studies, Hydraulic Engineering Series No. 45 (UILUENG-95-2007). 120 p.
2 Garcia, MH; Parsons, JD. 1996 Mixing at the front of gravity currents. Dynamics of Atmospheres and Oceans, 24(1-4), 197-205.
3 Parsons, JD; Garcia, MH. 1998 Similarity of gravity current fronts. Physics of Fluids, 10(12), 3209-3213.
4 Martin, JE; Garcia, MH. 2009 Combined PIV/PLIF measurements of a steady density current front. Experiments in Fluids, 46(2), 265-276.