Abstract: The invention concerns a system for real-time measurement of the instantaneous flow rate of a fluid with steady or unsteady flow in a conduit, comprising a flow member (1) for the fluid provided with at least two wall pressure taps (A,B), means (2) to measure pressure difference coupled with the two pressure taps (A,B), and programmed computing means (3) for real-time computing of flow rate by solving a nonlinear, ordinary, differential equation relating instantaneous flow rate to pressure difference, the pressure difference in said formula being positive or negative in relation to the variation in flow velocity of the fluid in the conduit and/or to the direction of flow of the fluid, characterized in that the flow member (1) comprises a filter (4) positioned between the two pressure taps (A,B) to increase pressure drop.

Abstract: The invention makes it possible to measure, in real time, the flow of a fluid that is incompressible while having an unsteady flow. The pressure measuring system is primarily comprised of a negative-pressure element (1) placed within the flow and provided with two wall pressure taps (A, B). A means (2) for measuring a pressure difference connected to the pressure taps (A, B) enables the following formula to be solved: dq(t)/dt+?(q(t))=?×?p(t) directly stemming from fundamental equations of fluid mechanics and/or: ?p(t) represents the pressure difference measured by the sensor; q(t) represents the sought volume flow rate, and; ? represents a function of the geometry of the negative-pressure element, of the fluid and of the flow q(t), the particularity of this formula being the consideration of the direction of flow in the second term of the left member of the formula.

Abstract: The invention makes it possible to measure, in real time, the flow of a fluid that is incompressible while having an unsteady flow. The pressure measuring system is primarily comprised of a negative-pressure element (1) placed within the flow and provided with two wall pressure taps (A, B). A means (2) for measuring a pressure difference connected to the pressure taps (A, B) enables the following formula to be solved: dq(t)/dt+?(q(t))=?X×?p(t) directly stemming from fundamental equations of fluid mechanics and/or: ?p(t) represents the pressure difference measured by the sensor; q(t) represents the sought volume flow rate, and; ? represents a function of the geometry of the negative-pressure element, of the fluid and of the flow q(t), the particularity of this formula being the consideration of the direction of flow in the second term of the left member of the formula.