Pressure Sensor Principles and Applications

A pressure sensor is a sensor capable of converting the measured pressure into an electrical signal. Its principle is mainly to use the deformation on the pressure loaded object or the pressure change in the pressure transfer medium (such as liquid or gas) to realize the measurement of pressure. The following will introduce the principle and application of two common pressure sensors respectively.

Strain gauge pressure sensor principle and application:

Strain gauge pressure sensors are a pressure measurement technique based on metallic materials. Its principle is to utilize the change in resistance of a metal strain gauge loaded in tension or compression working environment to measure pressure. When pressure is applied to the measured medium, the metal strain gauge deforms, thus changing its resistance value, and eventually converting the pressure into an electrical signal output.

Strain gauge pressure sensors have a wide range of applications including, but not limited to, industrial automation, biomedical, aerospace and other fields. In industrial automation, strain gauge pressure sensors can be used to measure the pressure of liquids and gases, and for pressure monitoring and control of pipelines, tanks and other vessels. In biomedicine, strain gauge pressure sensors can be implanted into the human body and used to measure pressure changes in the internal tissues of the human body, such as artificial hearts. In aerospace, strain gauge pressure sensors can be used to measure atmospheric pressure, liquid pressure, etc. of aircraft.

Resonant type pressure sensor principle and application:

A resonant type pressure sensor is a technique that utilizes the relationship between the resonant frequency and the measured pressure to measure pressure. According to the law of conservation of mass, when the measured pressure is applied to a thin film, it causes a slight deformation of the film, which changes the vibration frequency. For measurement, a resonant body is formed into a resonant loop with a resonant element (e.g., capacitor, inductor, etc.), and pressure measurement is achieved by measuring the change in resonant frequency.

Resonant pressure sensors are commonly used in applications requiring high accuracy and dynamic response, such as automotive manufacturing, aerospace, and instrumentation. In automotive manufacturing, resonant pressure sensors can be used to measure the cylinder pressure of an automotive engine, which is used to detect and control the engine's operating status. In aerospace, resonant pressure sensors can be used to measure aerodynamic parameters of aircraft, such as wind speed and airflow. In the field of instrumentation, resonant pressure sensors can be used to measure the pressure of various fluids, such as the pressure of liquids, gas pressure and so on.

Reasons why pressure sensors are easily broken:

Overload: when the pressure sensor is subjected to a pressure load that exceeds its rated range, it may cause damage to the pressure sensor. At this time, the mechanical structure of the pressure sensor may be damaged, resulting in failure to work properly.

Temperature effect: During the use of the pressure sensor, the temperature change inside the sensor will be caused by the temperature change of the working environment or its own heat generation. If the temperature is too high or too low, it may result in damage to the sensor element or performance degradation.

Liquid or gas intrusion: Some pressure sensors are designed with sealed structures, but if the seal is not tight or damaged, liquid or gas may intrude into the sensor interior, resulting in component corrosion or short circuit.

Mechanical shock: pressure sensors in the transportation, installation or use of the process may be subjected to mechanical shock, such as vibration, collision, etc., these shocks may lead to the sensor's internal structure of the loosening or destruction.

Electrical interference: in some special scenarios, such as electromagnetic radiation interference, voltage fluctuations, etc., may have an impact on the pressure sensor's internal electronic components, resulting in sensor failure or damage.