Fluid pressure sensing apparatus

Claim 1

A fluid pressure sensing apparatus comprising at least one fluid pressure sensor element, said fluid pressure sensor element comprising: a flat hollow structure adapted to extend transverse to the direction in which a fluid flows through a duct, said hollow structure having therein a partition which extends transverse to the flow direction so as to divide the interior of the hollow structure into an upstream chamber and a dowstream chamber, a plurality of total pressure measuring holes which extend through an upstream end wall of the hollow structure in the flow direction so that the upstream chamber of the hollow structure is open through said total pressure measuring holes, a plurality of static pressure measuring holes extending transversely to the flow direction through at least one wall of said hollow structure which extends parallel to the flow direction, so that said downstream chamber of said hollow structure is open through said static pressure measuring holes, wherein the total pressure may be measured from the upstream chamber and the static pressure may be measured from the downstream chamber of said hollow structure, and pressure outlets formed for the respective chambers and connected by respective connector pipes to associated measuring instruments, and further comprising a ridge-like auxiliary member for static pressure measurement projecting from the exterior of said hollow structure at a position downstream of said static pressure measuring holes.