Flow measurement with differential pressure sensors
Flow measurement often relies on differential pressure measurement. When gas passes through a defined restriction, a pressure drop is created. A differential pressure sensor detects this pressure difference and converts it into a usable electrical signal. Especially for low flow rates and minimal pressure losses ultra-low pressure sensors with high precision, stability, and repeatability are essential.
How differential pressure measurement works in flow applications
In many systems, gas flow is determined indirectly by measuring the pressure difference before and after a flow restriction such as an orifice plate, a Venturi tube, or a laminar flow element. The pressure difference can be correlated very accurately with volumetric flow. The larger the pressure drop, the higher the flow rate. A differential pressure sensor is therefore a key component in reliable flow measurement, particularly in medical devices, environmental monitoring, HVAC, and industrial instruments.
Why differential pressure sensors are used for flow measurement
A differential pressure sensor is a proven choice for compact and precise differential pressure flow measurement. It is well suited to systems that require accurate readings at ultra-low pressure levels, low power consumption, and stable long-term performance.
Typical applications include:
- medical respiratory devices
- HVAC systems
- filter monitoring
- leak detection systems
- air sampling equipment
- industrial gas flow control
Laminar flow element and flow calculation
A laminar flow element creates a defined resistance in the flow path. This generates a measurable pressure difference that is proportional to the volumetric flow under controlled conditions. It is for many applications the preferred measurement method.
With additional temperature and barometric pressure measurement the mass flow rate can be calculated from the volumetric flow.
For demanding flow measurement tasks, the combination of a high-performance differential pressure sensor and a suitable flow element offers an accurate and robust solution. This approach is particularly valuable for medical ventilators and spirometers as well as industrial HVAC systems. For tailored sensor solutions, All Sensors supports a wide range of technical requirements.