A magnetostrictive fluid level sensor is a type of electronic device used to measure the level of liquid substances in tanks or containers. It operates based on the magnetostrictive effect, which is the phenomenon where certain materials change their shape when subjected to a magnetic field. This effect is utilized to accurately determine the liquid level within a container.
Here's how a magnetostrictive fluid level sensor generally works:
Sensor Design: The sensor consists of a hollow, cylindrical tube made of a magnetostrictive material, often a ferromagnetic alloy. This tube is installed vertically within the tank or container whose liquid level needs to be measured.
Waveguide and Transmitter Coil: Inside the cylindrical tube, there is a smaller, non-magnetic waveguide wire. This wire usually runs along the centerline of the tube. At the top of the tube, a transmitter coil is wound around it. This coil generates a pulsed magnetic field.
Liquid Level Measurement: When an electrical current is passed through the transmitter coil, it generates a magnetic field that propagates down the waveguide wire. This magnetic field interacts with the magnetostrictive material of the tube and induces a mechanical strain in the tube.
Reflection of Pulse: The mechanical strain caused by the magnetic field generates an ultrasonic or guided wave along the waveguide wire. This wave travels both upwards and downwards along the wire.
Interaction with Liquid Interface: As the ultrasonic wave reaches the interface between the magnetostrictive tube and the liquid, a portion of the wave reflects back due to the change in the material's properties at the liquid level interface. The time taken for the pulse to travel down and return is measured.
Time-of-Flight Measurement: By measuring the time it takes for the ultrasonic wave to travel from the transmitter coil to the liquid interface and back, the sensor calculates the distance to the liquid surface. This measurement corresponds to the liquid level within the tank.
Electronics and Output: The sensor is equipped with electronic components to precisely measure the time of flight of the ultrasonic wave and convert it into a distance measurement. This distance measurement is then translated into a liquid level value, often displayed on a digital readout or transmitted to a control system.
Accuracy and Reliability: Magnetostrictive fluid level sensors are known for their high accuracy and reliability, making them suitable for applications where precise level measurements are crucial, such as in industrial processes, chemical storage tanks, and fuel storage tanks.
In summary, a magnetostrictive fluid level sensor uses the magnetostrictive effect to generate and measure ultrasonic waves in a magnetostrictive tube. These waves interact with the liquid interface and provide accurate measurements of the liquid level within a tank or container.