Static pressure measurement error at a wall tap of a flow nozzle for a wide range of Reynolds number

• The static pressure measurement error at a wall tap of a flow nozzle is examined.
• The static pressure measurement error is influenced by the diameter of the wall tap.
• The relations between the static pressure measurement error and tap Reynolds number is proposed.

The static pressure measurement error at a wall tap of a flow nozzle is examined for a wide range of Reynolds number. The static pressure measurement error is obtained using the measured discharge coefficient for the flow nozzle. The static pressure measurement error is influenced by the diameter of the wall tap and the viscosity of the working fluid. This paper presents several relations between the static pressure measurement error normalized by the wall shear stress and the tap Reynolds number, which is based on the diameter of the wall tap and the friction velocity. The best relation to reasonably explain the static pressure measurement error is proposed in this paper.