Hydraulic Circuit Simulator and Trainer

Welcome to the Hydraulic Circuit Simulator and Trainer — a free, browser-based hydraulic systems simulator designed for mechanical engineering students, fluid power technicians, vocational instructors, and maintenance engineers. This tool serves as a powerful FluidSIM online trainer alternative, providing interactive ISO 1219 schematic building, real-time oil flow animation, and comprehensive learning modes — all without installation, signup, or licensing fees.

Whether you are a beginner learning Pascal’s law or an advanced student designing multi-actuator circuits, this hydraulic trainer bridges the gap between textbook theory and hands-on practice. The simulator features 22 hydraulic components, 7 pre-built circuit templates, and 4 interactive learning modes (Simulate, Explore, Practice, Quiz).

1. Select a mode — Choose Simulate to build circuits, Explore to study concepts, Practice for calculation problems, or Quiz for self-assessment.
2. Load a pre-built circuit — Click any of the 7 circuit templates (Meter-In, Meter-Out, Regenerative, etc.) to instantly populate the canvas with a working circuit.
3. Or build from scratch — Click a component in the left palette, then click anywhere on the canvas to place it.
4. Connect components — Click a port (small circle) on one component, then click a port on another to draw a hydraulic line. Click the empty canvas between ports to add waypoints for custom routing.
5. Run the simulation — Click the Run button or press Space. Animated particles show oil flow direction and speed. Pressure readings appear on each connection.
6. Control actuators — Click directly on a DCV (directional control valve) to switch its spool position between Extend, Center, and Retract.

This hydraulic systems simulator includes all essential fluid power components drawn to ISO 1219 standard:

Power Source: Power Unit (Pump) — Configurable pressure (50–350 bar) and flow rate (5–100 L/min).

Directional Control Valves: DCV 4/3 (4-port, 3-position with Extend/Center/Retract), DCV 3/2 (3-port, 2-position for single-acting cylinders), and 2/2 Way Valve (on/off shut-off).

Flow Control: Flow Control Valve (1–60 L/min), Throttle Valve (5–100% opening), Check Valve, Pilot Check Valve, and Shuttle Valve.

Pressure Control: Relief Valve (50–350 bar), Pressure Reducing Valve (20–200 bar), Sequence Valve (30–300 bar), and Counterbalance Valve.

Actuators: Single-Acting Cylinder, Double-Acting Cylinder (configurable bore, rod, stroke), and Hydraulic Motor (5–100 cm³/rev).

Utility: T-Connector, Accumulator (20–200 bar precharge), Pressure Gauge, Flow Meter, and Filter.

Place components by clicking in the palette then clicking the canvas. Move by dragging. Connect ports by clicking port circles. Add waypoints by clicking empty canvas during connection. Drag segments to adjust routing. Right-click a connection to clear waypoints.

7 Pre-Built Circuit Templates: Meter-In, Meter-Out, Regenerative, Sequence, Bleed-Off, Counterbalance, Load-Holding, Accumulator, and Safety circuits.

Simulation features: Animated oil flow particles, pressure computation, cylinder extension/retraction, motor rotation, live readout panel, interactive DCV control (click to switch spool position), and circuit validation warnings.

Component manipulation: Rotate 90° (right-click or toolbar), Duplicate (right-click), Delete (right-click, toolbar, or Delete key), Undo (Ctrl+Z, up to 50 states), Edit Parameters (right-click → Info).

Explore mode provides an interactive hydraulic reference library across Fundamentals (Pascal’s Law, Flow-Pressure-Power, Hydraulic Advantage, Continuity Equation), Components (12 detailed entries), and Circuits (5 topologies with descriptions and applications).

Practice presents 12 randomised calculation problems covering cylinder force, motor speed/torque, pump flow, system power, regenerative circuits, area ratios, and volume relationships. Step-by-step solutions provided.

Quiz generates a 15-question assessment (8 MCQ + 7 numeric) with immediate feedback, correct answers, and final score classification.

Use the mark-bar above the canvas to annotate your circuits:

• Move tool — select, move, resize, duplicate, rotate, and delete annotations. Double-click a text label to edit it.
• Sketch tool — freehand drawing with pressure sensitivity. Pick colour and width from the dropdown. Stays active after each stroke for continuous drawing.
• Shape tool — draw rectangles, circles, ellipses, arrows, lines, double-arrows, or text labels. Pick shape type, colour, width, and fill from the dropdown.
• Toggle annotations — show/hide all annotations without deleting them.
• Clear annotations — remove all or a category (sketches only, shapes only).
• Export PNG — save the canvas (with annotations) as a PNG image.

Zoom & Pan: Ctrl+Scroll to zoom towards cursor, Ctrl+Drag or H key for pan mode, pinch-to-zoom on touch. Toolbar buttons: Zoom In/Out, Pan Toggle, 1:1 Reset, Fit All. Right-click empty canvas toggles pan mode.

Fullscreen: Click the fullscreen button (bottom-right) to expand the canvas with the component palette.

Benchmarked against FESTO FluidSIM, the simulator ships with three industrial-grade panels below the canvas:

Circuit Diagnostics — a live design-and-safety checker that runs every second. It flags missing pumps or relief valves, unconnected components, actuators with unwired ports, over-set pumps that waste energy, and cases where the pump is running but flow is blocked. A coloured summary pill shows at a glance whether all checks pass (green), there are warnings (amber), or there are errors (red).

Fault Injection — inject real-world failure modes while the simulation runs: pump failure (total loss), external leak (50% pressure drop), blocked filter (flow restriction), oil overheating (viscosity drop, 30% flow loss), relief valve stuck closed (no pressure cap), cavitation (suction loss, 40% flow down), and air ingress (spongy response). Use the dropdown to pick a fault and the Status readout will switch to red with the fault name; click Clear fault to recover.

Oscilloscope & Data Logger — a four-channel scrolling scope. Assign any gauge, flow meter, cylinder, motor, or pump in the circuit to any of CH1–CH4 and watch live pressure, flow, extension, RPM, or temperature traces over a 10-second window. Each channel auto-scales independently. Use Pause to freeze the trace, Clear to reset the buffer, CSV to export the entire time-series for analysis in Excel/MATLAB, and PNG to save a watermarked screenshot for reports. This is the fastest way to capture step-response, stall, sequencing, or fault recovery behaviour for coursework and lab evidence.

Keyboard shortcuts: Space = Run/Stop, Ctrl+Z = Undo, Ctrl+Shift+Z = Redo, E/C/R = Set all DCVs to Extend/Center/Retract, Delete = Delete selected (annotation or component), D = Duplicate component, Escape = Exit pan mode / Cancel.

Zoom shortcuts: Ctrl+= Zoom in, Ctrl+- Zoom out, Ctrl+0 Reset zoom, Ctrl+1 Fit all, H Toggle pan mode.

• Always start with a Power Unit — every hydraulic circuit needs a pump.
• Add a Relief Valve early to protect against over-pressure.
• Use pre-built circuits to learn — load, study, modify, observe.
• Rotate components for compact, readable schematics.
• Right-click for options — Info, Duplicate, Rotate, Delete.
• Watch pressure readings during simulation — unexpected values indicate incorrect valve settings or missing return paths.
• Master Practice mode calculations before attempting the Quiz.