Flow direction sensor

A method for making an apparatus to determine a flow direction in a fluid, the method comprising:

• forming a substrate including a barrier having a first barrier surface and a second barrier surface;
• locating a first flow sensor a first distance from the first barrier surface, the first flow sensor to generate a first sensor signal;
• locating a second flow sensor a second distance from the second barrier surface, the second flow sensor to generate a second sensor signal;
• and
• coupling the first flow sensor and the second flow sensor to the substrate, the first sensor signal and the second sensor signal to be processed to determine the flow direction in the fluid.

A method for determining one or more fluid flow properties of a fluid flowing in a conduit, the method comprising:

• providing a barrier, the barrier having a first barrier surface and a second barrier surface, in the fluid to cause a difference between upstream characteristics and downstream characteristics of the fluid flowing in the conduit;
• locating a first flow sensor a first distance from the first barrier surface, the first flow sensor to generate a first sensor signal;
• locating a second flow sensor a second distance from the second barrier surface, the second flow sensor to generate a second sensor signal;
• and
• processing the first sensor signal and the second sensor signal to determine the one or more fluid flow properties of the fluid flowing in the conduit.

A method for determining one or more fluid flow properties of a fluid flowing in a conduit, the method comprising:

• providing a barrier, the barrier having a first barrier surface and a second barrier surface, in the fluid to cause a difference between upstream characteristics and downstream characteristics of the fluid flowing in the conduit;
• locating a first flow sensor a first distance from the first barrier surface, the first flow sensor to generate a first sensor signal;
• locating a second flow sensor a second distance from the second barrier surface, the second flow sensor to generate a second sensor signal;
• processing the first sensor signal and the second sensor signal to determine the one or more fluid flow properties of the fluid flowing in the conduit;
• recording a sequential plurality of fluid flow sensor readings and a next fluid flow sensor reading following the sequential plurality of fluid flow sensor readings from the first flow sensor signal;
• generating a curve from a least squares fit to the sequential plurality of fluid flow sensor readings;
• generating a predicted next data point from the curve;
• comparing the next fluid flow sensor reading to the predicted next data point and generating a difference between the next fluid flow sensor reading and the predicted next data point;
• and
• invalidating the next fluid flow sensor reading, if the difference is substantially greater than zero.

A system to monitor a fluid flow direction in a fluid that flows between a patient and ventilator, the system comprising:

• a fluid flow direction sensor including a substrate including a barrier having a first barrier surface and a second barrier surface, the fluid flow direction sensor to detect the fluid flow direction in the fluid;
• a first flow sensor to generate a first velocity sensor signal, the first flow sensor located at a first sensor distance from the first barrier surface;
• and
• a second flow sensor to generate a second velocity sensor signal, the second flow sensor located at a second sensor distance from the second barrier surface, wherein the first sensor distance and the second sensor distance are selected to disturb the fluid flowing in the conduit in such a way as to enable determination of the one or more fluid flow properties from the first velocity sensor signal and the second velocity sensor signal;
• and
• a conduit coupled to the fluid flow direction sensor, the conduit to couple to the patient and the ventilator.

A system to monitor a fluid flow direction in a fluid that flows between a patient and ventilator, the system comprising:

• a fluid flow direction sensor including a barrier, the fluid flow direction sensor to detect the fluid flow direction in the fluid;
• a conduit coupled to the fluid flow direction sensor, the conduit to couple to the patient and the ventilator;
• and
• a control system to couple to the fluid flow direction sensor to monitor the fluid flow direction;
• and wherein the fluid flow direction sensor incudes a first sensor and a second sensor separated by the barrier.