2025-11
05With stable flow, comes stable measurement
Student A asked:
The most commonly used gas mass flow meters currently are thermal flow meters and laminar differential pressure flow meters. The design and development time of thermal mass flow meters is relatively early, and there are also many domestic research and development manufacturers, which have been widely used in many fields. YIDU focuses on the research and development of laminar differential pressure gas mass flow meters and controllers. Many customers have reported that YIDU flow meters are stable and reliable in measurement. Why are YIDU flow meters stable and reliable?
Answer from YIDU pre-sales engineer:
To understand the stable and reliable technical principles of the YIDU flowmeter, we must first start with the flow state. The flow state of gas is generally divided into laminar flow and turbulent flow (transition flow is not discussed here). The flow of gas in pipelines is generally turbulent due to various disturbance factors. British physicist Peter Bradshaw once said, "The undisputed fact about turbulence is that it is the most complex type of fluid motion." Turbulence, also known as turbulence, disturbance, or turbulence, as the literal meaning suggests, is elusive in its regularity. It is undoubtedly difficult to explore accurate flow measurement principles in this uncertain flow state.
Laminar flow is a flow state that is opposite to turbulence. Simply put, it means that when the velocity of gas flow is relatively slow and the influence of viscous forces on the flow field exceeds that of inertial forces, the disturbance of flow velocity and direction in the flow field will gradually weaken due to the action of viscous forces, ultimately presenting a layered flow state along the flow direction, which is called laminar flow.
Student A asked:
Why is it said that stability is measured under laminar flow conditions?
Answer from YIDU pre-sales engineer:
In laminar flow, there is no radial disturbance in the gas. By opening pressure holes on the wall and using sensors, the pressure value at that point can be accurately obtained without fluctuations caused by turbulent airflow. More importantly, in the layer
In a flowing state, gas follows the Hagen Poiseuille law:
That is to say, the flow rate is directly proportional to the differential pressure, which is a definite relationship. For a fixed flow channel and a fixed gas, all parameters in the Hagen Poiseuille formula except for flow rate Q and differential pressure Δ P are fixed values. Therefore, each time the sensor collects a differential pressure signal, it corresponds to a unique and determined flow rate value. This is really as stable as it gets.
The YIDU laminar differential pressure flowmeter is designed and developed based on such an accurate measurement principle, and the measurement is carried out in laminar flow state. The principle is accurate, and the laminar flow sensor measures accurately, making the measurement repeatability and stability of the YIDU flowmeter reach an advanced level in the industry. The products delivered to customers will always be synonymous with stability and reliability!