1、 Main characteristics of wing wind measurement device
The wing wind measuring device, like various other wind measuring devices, is a measuring tool for monitoring the combustion air volume of boilers. It can be used to measure the air flow rate of boilers. It can be directly installed on the inlet of the supply fan and the cold and hot air ducts between the supply fan and the burner. Due to its unique structure, the requirements for the front straight pipe section during installation are much lower than other measuring elements, and it is not easy to block. It is suitable for maintenance and repair The requirements for the cross-sectional shape of the air duct and the impact on the airflow flow within a certain range before and after the device are superior to other measuring elements. This device can generate a pressure difference signal of 0-100mmH20 or greater, which is converted into a standard electrical signal (0-10mA or 4-20mA) by a differential pressure transmitter. This signal is stable and can achieve safe and economic operation of the boiler.
2、 Composition of wing wind measurement device
The wing wind measurement device consists of wing sensors, valve groups, and differential pressure transmitters.
3、 Measurement principle of wing wind measuring device
This device consists of a wing installed in a rectangular or circular air duct, a differential pressure measuring device, and a section of air duct. Each throttle line of the wing is divided into four sections, with three sections being curved plates with respective curvature radii, and the fourth section being straight plates. According to the principles of fluid mechanics, when the airflow in the duct flows through the wing measurement device, as shown in Figure 1, there is a flow around the wing surface and a pressure difference between stagnation point A and chord point B (B '). The pressure at stagnation point A is full pressure, and the pressure at chord point B (B ') is static pressure. Due to the contraction of the flow section at B (B ') and the decrease in static pressure, the pressure difference between A and B (B') is relatively large. There is a certain functional relationship between the pressure difference △ P and the airflow velocity V (or flow rate 0): V=f (OP.R)
Constant velocity on V, Δ P - pressure difference, R - cross-sectional shrinkage ratio of flow
4、 The main advantages of the wing wind measurement device are:
1. This device has a unique wing shaped throttle element, which can generate a large differential pressure signal and ensure stable and reliable measurement; High accuracy.
2. Adopting a dual wing or multi wing structure, the device itself has a short length and low requirements for the length of the front and rear straight pipe sections.
3. Due to its streamlined design on the end face, the throttling element of this device has low fluid resistance and pressure loss, resulting in a pressure loss not exceeding 14% of the differential pressure value; Within the range of high flow rate (30%~10%), the measurement error is less than 2% of high flow rate.
4. No movable parts, easy to install and maintain.
