Fluid sensor system, computing device, and flow direction estimation method

A controller for estimating a flow direction of a fluid in a flow path on the basis of an output from a sensor including a heating element arranged on a flow path forming surface that forms the flow path of the fluid and configured to generate heat according to electric power supplied from an external power supply and an outer peripheral sensor unit including three or more sensor pairs provided at intervals in a circumferential direction to surround the heating element, each sensor pair of the three or more sensor pairs including two temperature sensors configured to sandwich the heating element and arranged opposite each other, wherein the controller is configured to:

• identify a sensor pair in which an output difference between an output value corresponding to a temperature detected by one temperature sensor of the sensor pair and an output value corresponding to a temperature detected by the other temperature sensor of the sensor pair is largest among the three or more sensor pairs;
• identify other sensor pairs adjacent to the identified sensor pair in the circumferential direction;
• and
• estimate the flow direction of the fluid on the basis of the output difference in the sensor pair having the largest output difference and output differences in the other sensor pairs adjacent to the sensor pair in the circumferential direction.

A flow direction estimation method of estimating a flow direction of a fluid in a flow path on the basis of an output from a sensor including a heating element arranged on a flow path forming surface that forms the flow path of the fluid and configured to generate heat according to electric power supplied from an external power supply and an outer peripheral sensor unit including three or more sensor pairs provided at intervals in a circumferential direction to surround the heating element, each sensor pair of the three or more sensor pairs including two temperature sensors configured to sandwich the heating element and arranged opposite each other, the flow direction estimation method comprising steps of:

• identifying the sensor pair in which an output difference between an output value corresponding to a temperature detected by one temperature sensor of the sensor pair and an output value corresponding to a temperature detected by the other temperature sensor of the sensor pair is largest among the three or more sensor pairs;
• identifying other sensor pairs adjacent to the identified sensor pair in the circumferential direction;
• and
• estimating the flow direction of the fluid on the basis of the output difference in the sensor pair having the largest output difference and output differences in the other sensor pairs adjacent to the sensor pair in the circumferential direction.