Apparatus for measuring fluid flow rate in a two-phase fluid stream

摘要

A pitot tube type apparatus (10) is specifically adapted for measuring fluid flow rate in a gas flow containing entrained liquid droplets. The probe (20) includes first and second probe means (22,24) which are interconnected through pressure transmitting lines (12,14) to a pressure differential indicator (16). The first probe means (22) has a total pressure sampling port (21) opening directly upstream into the gas flow. The second probe means (24) has a static pressure sampling port (25) opening normal to the gas flow at a location downstream of the total pressure sampling port (21). A flat plate (30) is mounted to the first probe means and extends therealong in the plane of the static pressure sampling port (25) to a point adjacent and downstream of the static pressure sampling port so as to cause the boundary layer to be established over the static pressure sampling port (25). The ports (21,25) are also sized to be substantially greater than the size of the liquid droplets entrained in the gas. A flow of blow-back gas is intermittently passed through the transmitting lines to clear the lines and the probe means of any accumulating liquid.