This simulator operates an air-powered positioning rig — a receiver, filter-regulator, five-port valve, adjustable exhausts and magnetic end sensors driving a cutaway profile-barrel cylinder. Adjust bore, rod diameter, stroke, regulated supply pressure, opposing load, seal breakaway resistance, supply/exhaust orifice areas and cap-side leakage, then watch compressible chamber pressures build and decay.
• A real-time 3D cutaway workbench of the profile-barrel cylinder and compressible chambers, piston magnet/rod/carriage, air receiver and compressor head, filter-regulator and gauge, 5/3 closed-center solenoid valve, meter-out exhaust controls and silencers, and magnetic end sensors with an instrument panel, with home view, focus-selected-part, show-full-enclosure, exploded view, auto-rotate, expand and show/hide labels controls. • Four action controls: extend cylinder, retract cylinder, center valve/block ports, and isolate supply/vent chambers. • Playback controls: pause/resume, 0.1 s and 1 s step advances, and five playback speeds (10× and 100× slow motion, real time, 10× faster, one minute per second). • A Curves & measurements tab with a live cap/rod chamber pressure comparison chart, a motion-and-energy history chart, the full model equations (chamber volumes, ideal-gas law, force balance, compressible orifice flow, choke condition) and snapshot measurement readouts covering position, velocity, chamber pressures, net force, effective areas, theoretical push/pull capacity, port flows, chamber volumes and mechanical power. • An Experiments tab with four guided fixtures (build chamber pressure, restricted exhaust, load above available force, leak and trapped-air hold) and a Model verification bench that runs independent deterministic checks against a fresh model without disturbing your live trial, plus a timestamped event log and a copyable trial report. • A Learn & assess tab with guided lessons, a knowledge-check quiz with reset, and a written model-scope statement with a technical reference link.
Unlike hydraulic oil, air is compressible, so chamber pressure does not jump instantly to the regulated supply value when a port opens — it builds gradually as the ideal-gas relation (pressure proportional to mass and temperature, inversely proportional to volume) plays out while air flows in through a compressible orifice. The cap chamber fills before substantial piston movement occurs, and outgoing air through the meter-out exhaust restriction develops backpressure that changes both net force and travel speed.
This also means a closed-center valve does not create a rigid mechanical lock: even with both work ports sealed, trapped air is compliant, and changing chamber volume as the piston moves still changes pressure, allowing some give under load.
The ideal-gas law inside the simulator uses absolute pressure (gauge pressure plus atmospheric), but the net force on the rod is computed from gauge pressures, since atmospheric pressure acts equally outside the rod. The model uses a discharge coefficient of 0.7 and specific-heat ratio of 1.4 for compressible orifice flow, switching to choked flow below the critical pressure ratio.
This is an isothermal, lumped-chamber model with overdamped piston motion — it does not include inertia, bounce, stick-slip, thermal transients, a cushion model or compressor cycling, and constant supply pressure plus symmetric opposing resistance are teaching assumptions. It is not a certified valve-sizing tool, and drawn equipment proportions and flow-direction markers are illustrative rather than manufacturer CAD.
Air is compressible, so pressure builds gradually according to the ideal-gas relation as mass flows into the chamber through a restrictive orifice. The simulator shows the cap chamber filling and pressure rising before substantial piston movement occurs, unlike an idealized incompressible-fluid assumption.
No. Even with both work ports sealed, the trapped air is still compressible, so changing chamber volume as the piston moves under load still changes pressure and allows some compliance. A closed pneumatic valve center is not equivalent to a mechanical lock.
A smaller meter-out orifice area limits outgoing mass flow, which develops backpressure in the exhausting chamber. That backpressure reduces the net pressure force driving the piston, slowing travel compared to an unrestricted exhaust at the same supply pressure.
No. It is an isothermal, lumped-chamber teaching model with idealized compressible-orifice flow — it omits piston inertia, thermal transients, cushioning and compressor cycling. A certified pneumatic circuit design requires manufacturer flow-coefficient data and a full engineering analysis.