This simulator fills a transparent open vessel with liquid and lets you inspect a horizontal test plate mounted above the floor. As the water level rises and falls, you see when the plate becomes submerged, what gauge pressure it sees and how much downward force that pressure creates.
• A 3D open vessel with a changing free surface, a horizontal test plate, a pressure indicator and a depth-pressure profile. • Four sliders: commanded liquid depth (0.3-3 m), liquid density (800-1200 kg/m3), plate height above the floor (0.1-1.5 m) and plate area (0.01-0.1 m2). • Six live readouts: liquid level, plate submergence, gauge pressure at the plate, absolute pressure, gauge force on the plate and net filling flow in L/s. • Two presets: Deeper water (plate gauge pressure approaches rho g times 2.9 m) and Dry plate (pressure and force are zero while the plate is above the water).
For a liquid at rest the gauge pressure at the plate is p = rho g max(h - z_plate, 0), so it depends only on density and the depth of liquid above the plate, not on the vessel width. Absolute pressure adds atmosphere: 101.325 kPa + p_gauge. The force on a face is F = p A, so the same pressure on double the area gives double the force. The filling animation uses a first-order level model, dh/dt = (h_command - h) / 2, in a 1 m2 tank.
Pressure is computed for a uniform incompressible liquid at rest; the smooth filling uses a separate lumped level model, and sloshing and velocity head are ignored. The force shown is the gauge load on one face, not the net force on a freely submerged plate, which would also include pressure on the opposite face. Raise the plate to watch the gauge pressure fall to zero, then change the density to see the profile slope change.
Gauge pressure is measured relative to the surrounding atmosphere, while absolute pressure adds atmospheric pressure (101.325 kPa in this model) to the gauge value.
Not at a fixed depth. For a liquid at rest, local gauge pressure is set by density, gravity and the depth below the free surface, so a wide tank and a narrow tank give the same pressure at the same depth.
Force equals pressure times area, F = p A. At the same gauge pressure, a plate with double the area carries double the force.
It assumes a uniform incompressible liquid at rest. Sloshing, velocity head and compressibility are ignored, and the plate force shown is the gauge load on one face only.