• By embedding in a well, the velocity and direction of underground water can be measured.
  • Observing range is from 0.01 to 1 cm/minute.
  • The minimum diameter of well is 50 mm, limited by the size of probe.
  • Lightweight makes it quite suitable for field observation.
  • Easy to operate the instrument.

The sensor to measure underground water flow has a tubular shape with a heater being embedded in the center and 16 temperature sensors being placed in a circular arrangement. As shown in the figure 1, the probe is surrounded with strainer. Around the strainer, the current forms "laminar flow" and such a temperature-modulated flow has a unique temperature istribution in relation to flow velocity and direction. This new probe can be used in the underground stratum even if a diameter of well is similar to that of bowling.

Figure 1


Measuring range Velocity: 0.01 - 1.0cm/min.
Direction: 0 - 360
Accuracy Velocity: 10% Direction: 10

Display on PC

Velocity: Digital Indication
Direction: 360
Circular LCD indication
Output RS-232C


Cable length 30m in standard (Expandable)
Size 34mm dia. X 560mm

In figure 2, it gives an example of measurement. The curve and circle represent the temperature distribution after 60 minutes of starting heater. When probe is put in the underground water, temperature distribution caused by flow is different from place to place around probe surface. The temperature at ch1 has a relative small increase, but the opposite point (ch9) changes a lot in comparison to ch1 point.

figure 2