Pitot tubes, elbow meters, and rotameters are flow-sensing instruments that measure flow through different physical mechanisms: the pitot tube measures local point velocity by converting velocity (kinetic) head into stagnation (static) pressure head via Bernoulli's principle, an elbow meter derives flow from the differential pressure naturally created between the inner and outer radius of an existing pipe bend, and a rotameter (variable-area meter) infers flow rate from the equilibrium vertical position of a float in a tapered tube, where weight, buoyancy, and drag force balance. These belong to flow-measurement theory in industrial instrumentation, extending differential-pressure and variable-area sensing principles introduced for orifice and Venturi meters to point-velocity measurement, no-additional-loss installations, and non-electrical/indicating instrumentation.
Pitot tubes, elbow meters, and rotameters are flow-sensing instruments that measure flow through different physical mechanisms: the pitot tube measures local point velocity by converting velocity (ki…