Short answer: Greenhouse irrigation pumps, pipes and zones should be sized from simultaneous emitter flow, required pressure at the most demanding outlet, elevation, pipe and filter losses, treatment equipment, flushing demand, irrigation duration and future expansion. Maximum pump flow or greenhouse area alone cannot define the system.
Mark greenhouse blocks, rows, crop type, emitter or sprinkler spacing, zone valves, filters, fertigation room, storage tanks, elevation and pipe routes. Confirm whether all zones operate separately, in groups or simultaneously. A hydraulic calculation needs the real layout and operating sequence.
Zone flow begins with the number of active outlets multiplied by nominal outlet flow, then considers flushing, control and manufacturer design requirements. Use the selected emitter or nozzle data at the intended pressure. Separate nursery mist, drip irrigation, fog cooling and hydroponic circulation because they can have very different pressure and water-quality needs.
| Pressure component | Calculation input |
|---|---|
| Outlet operating pressure | Required pressure for emitters, sprinklers, fog nozzles or channels. |
| Pipe friction | Flow, pipe inside diameter, length, fittings and material. |
| Elevation | Height difference between water level, pump and highest or most remote outlet. |
| Filters and treatment | Clean and dirty pressure loss across filters, valves and treatment equipment. |
| Control margin | Required regulation and operating range without hiding incomplete design. |
Compare pump curves at the required flow and total dynamic head. Confirm efficiency, motor power, voltage, phase, frequency, speed control, materials, seal, suction condition and available net positive suction head where relevant. Maximum flow and maximum head usually occur at different points and should not be used together.
Choose main, submain and lateral diameters to balance pressure variation, velocity, flushing, energy and cost. Small pipes can increase loss and pump power; oversized pipes can add cost and may not provide suitable flushing. Use recognized hydraulic calculations and the actual internal diameter.
Divide zones by crop, greenhouse block, elevation, root-zone system, irrigation duration and valve capacity. Similar crops may still need separate zones if planting dates or sunlight differ. The controller should prevent unsupported combinations that exceed pump, filter or dosing capacity.
Confirm working tank volume, refill rate, low-level protection, suction pipe, screens, priming and overflow. Protect pumps from dry running, excessive pressure and blocked flow. Where crop risk is high, evaluate duty and standby pumps, manual bypass and backup power.
Approved irrigation layout and zone schedule
Emitter or nozzle data sheet
Hydraulic calculation and pump duty point
Pump curve, motor and control data
Pipe diameter, valve and filter schedule
Pressure-gauge and flow-meter locations
Flushing, leak, uniformity and alarm test records
Select it from simultaneous zone flow and total dynamic head using the pump curve and system layout.
Only if pump, filter, dosing, pipes and water supply are designed for that operating combination.
Possible causes include undersized pipes, excessive flow, blocked filters, elevation, leaks or incorrect regulation.
It may help varying zones and pressure control, but selection depends on motor, system curve, controls and operating range.
Use the drip layout guide, fertigation-room guide and irrigation system category.
Send the layout, crop, outlet data, zones, elevation and water source through the contact page for a hydraulic-input checklist.