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FURNESS CONTROLS
Laminar Flow Element - Air/Gas from 0.1 mL/min to 40,000 L/min
The FCO96 Series of Laminar Flow Elements (LFE) is a family of primary flow devices for measuring low volume air and gas flow rates from 0.1 mL/min to 40,000 L/min. The FCO96 LFEs provide accurate and repeatable measurement of low flow rates encountered in sampling systems, injectors, and respiratory applications...
- No square root extraction required
- Generate very low pressure drop across the element
- Suitable for pressures up to 8 bar
Flow measurements are often made by an orifice plate, venturi or nozzle, where the differential pressure generated is related to the flow rate through a square law. FCO96 laminar flow elements have a linear relationship between differential pressure and flow rate, which allows for much higher flow rates. Laminar flow conditions are achieved below a Reynolds number of 2000.
FCO96 laminar flow elements generate a low differential pressure, offering little restriction to flow. A typical value at full flow is 10 mmH20 (98 Pa). Suitable measuring instruments are the Furness Controls range of micromanometers and pressure transmitters.
Theory
Laminar flow conditions exist in a gas when the Reynolds number is less than the critical number of 2000. Above this number, the fluid state is considered turbulent. Below this number, the pressure difference over a given length is linear with the flow rate.
Furness Controls FCO96 Laminar Flow Orifices are designed around a Reynolds number of 500, which places them well within the laminar flow range. Each device is designed to provide expansion/reduction chambers at the inlet/outlet, so that the flow is linear to the differential pressure at the measurement points.
