Answer / carl_ellis

1)why we are using mostly Ultrasonic Flow meters to measure
flow, rather than Radar waves? 2)why we are using Ultrasonic
waves and Radar waves to measure the Level?

Most fluids will 'conduct' ultrasonic energy. Conduction
is necessary because the energy needs to originate in a
transmitter transducer, pass through the liquid and be
received by a receiver transducer. The movement of the
fluid changes the sonic velocity of the energy, which is
measured to then calculate a flow rate.

Many fluids either reflect the radar frequency signal or
absorb the signal so that there is not enough energy left to
measure.

Radar frequencies reflect when a radar signal encounters a
dielectric difference. So radar easily passes through air,
with a low dielectric constant, but reflects back from
water, which has a high dielectric. So radar is useful for
level detection with liquids or solids that have a
dielectric higher than the minimum required to reflect
energy back to the transducer.

Ultrasonic energy reflects from most liquids and solids so
it can be used for level measurement.

Carl Ellis
Measure First

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