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20 Lawrence K. Wang et al.

Fig. 6. Static-pressure-sensing devices: (A) wall type; (B) static tip; (C) low pressure.

for the system. Gas velocities may be obtained by measuring either the gas kinetic or
the velocity pressure.
Total pressure (P ), which includes static pressure (P ) plus velocity pressure (P ), is
T s v
measured by placing an impact tube so that it faces directly into a gas stream. Static
pressure must be measured separately and subtracted from this total pressure to obtain

Fig. 7. Pressure-drop measurement.