CFD-100Portable current meterIt is a mainstream water survey flow velocity measurement instrument developed after years of research and design for hydrological stations, factories and mines, environmental monitoring stations, farmland irrigation and drainage, hydrogeological surveys and other departments to measure the flow velocity of open channels in the field. The instrument has a simple structure, is lightweight and convenient, consumes less power, has complete functions, high degree of automation, and is stable and reliable. It meets the national standard for open channel flow measurement and is equipped with an 80 degree high-temperature propeller. It is currently a new type of portable flow velocity measurement instrument in China.

CFD-100Portable current meterAdopting a new type of vortex sensor, it has higher accuracy and is more convenient to use compared to traditional flow meters. This sensor was successfully developed by a specially appointed technical consultant, doctoral supervisor, and technical engineer at the end of 2004. The spiral angle, pitch, manufacturing process, and materials of the rotary plasma have been redesigned, with rotary plasma diameters of Φ 15mm and Φ 12mm respectively (the rotary plasma reflective surface adopts advanced electroplating technology, which is wear-resistant and has strong signals); Starting flow rate ≤ 1cm/s; The indicators such as starting flow rate, speed measurement range, linearity, concentricity, calibration coefficient, and mean square deviation have been greatly improved and enhanced compared to previous sensors.

OneCFD-100Portable current meterTechnical features:

Flow velocity measurement range: 0.01-4m/s (up to 5.00m/s)

Sampling time: 1 to 99 seconds, optional

• Working water depth: ＜ 20m

Flow measurement error: ≤ 1.5%

• Display screen: 4 × 16 bit LCD display

• Measurement method: Pole positioning measurement

• Temperature range: -20 ℃ -50 ℃

• Power supply: DC8.4V lithium-ion rechargeable battery, which can work continuously for more than 40 hours after being fully charged

• Purpose: Suitable for measuring and directly displaying the flow velocity of water at predetermined measurement points in channels, estuaries, and reservoirs

• Complete set of instruments: including flow meter, display instrument, and cable, no need to purchase additional supporting instruments

IICFD-100Portable current meterMeasurement principle:

This instrument is designed based on the principle of velocity area method for open channel flow measurement. By measuring the velocity, the flow rate Q=V · S (S is the cross-sectional area) can be obtained.

1. Measurement of water flow velocity:

When measuring water flow velocity and flow rate, the propeller rotor flowmeter is driven by hydraulic power to rotate, and the built-in signal device generates a speed signal. The flow rate is calculated by the following formula:

KN

V＝———————— ＋ C（m/s）

T

In the formula: V: Average flow velocity during the flow measurement period (m/s)

K: Hydraulic pitch C of blade: constant of flowmeter

T: Duration of flow measurement (unit: S) N: Number of signals during the T period

When using this instrument, K and C are constants. When measuring flow, as long as T and N are measured, the flow velocity can be calculated