Hydraulic Circuit Simulator
Pump • DCV • Cylinder • Relief Valve • Pressure • Flow — Simulate • Explore • Practice • Quiz
Understanding Hydraulic Circuits — Free Interactive Simulator
A hydraulic circuit uses pressurized fluid to transmit power and perform work. Based on Pascal's law, pressure applied to a confined fluid is transmitted equally in all directions, enabling small forces to generate large output forces through area ratios. Hydraulic systems are used in construction equipment, industrial presses, aircraft controls, and manufacturing machinery. Our interactive simulator lets you build and analyze a complete hydraulic circuit with a pump, directional control valve (DCV), double-acting cylinder, and pressure relief valve. Adjust system parameters in real time to see how pressure, flow rate, and cylinder geometry affect force, speed, and power output.
Hydraulic Cylinder Force and Speed Calculations
The extension force of a hydraulic cylinder is calculated as Fext = P × Ap, where P is system pressure and Ap = π/4 × D² is the full piston area. During retraction, force acts on the annular area Aa = Ap − Ar, where Ar = π/4 × d² is the rod cross-section area. This means retraction force is always less than extension force at the same pressure. Piston speed depends on flow rate and area: v = Q / A. Since the annular area is smaller, retraction speed is faster than extension speed for the same flow rate — a key design consideration.
Directional Control Valves and Circuit Operation
A 4/3 directional control valve has four ports (P for pump, T for tank, A and B for actuator) and three positions. In the extend position, pump flow goes from P to A (cap end of cylinder) while return oil flows from B to T. In the retract position, flow is reversed: P to B, A to T. In neutral position, all ports may be blocked (closed-centre) or pump flow may return directly to tank (open-centre). The pressure relief valve protects the system by opening when pressure exceeds its setting, diverting excess flow back to the reservoir.
Hydraulic Power and System Efficiency
Hydraulic power is calculated as Phyd = p × Q / 600 (in kW, where p is in bar and Q is in L/min). This represents the energy delivered to the fluid by the pump. System efficiency depends on volumetric losses (internal leakage) and mechanical losses (friction). In practice, overall system efficiency ranges from 60% to 85%. Understanding power flow helps engineers select appropriate pump sizes and motor ratings for hydraulic installations.
Who Uses This Simulator?
This hydraulic circuit simulator is designed for mechanical and fluid power engineering students studying hydraulic systems, vocational trainees learning circuit design and troubleshooting, maintenance technicians understanding valve operations, and instructors teaching fluid power fundamentals. It provides hands-on understanding of hydraulic circuit behavior without requiring physical laboratory equipment or expensive fluid power training rigs.
Explore Related Simulators
If you found this hydraulic circuit simulator helpful, explore our Pascal's Law Simulator, Fluid Flow in Pipes, Bernoulli's Principle, and Pressure Vessel Calculator for more hands-on fluid mechanics practice.