Patent ID: 7418878

Claim:
An anemometer for measuring a flow property of a fluid flowing through a conduit, comprising: a first sensor in the conduit and immersed in the fluid, wherein: the first sensor has a first resistance that changes with temperature; the first sensor is heated by one of (1) a first current flowing through the first sensor and (2) the first current flowing through a heating element thermally coupled to the first sensor, the first sensor exchanging heat with the fluid; a second sensor in the conduit and immersed in the fluid, wherein: the second sensor has a second resistance that changes with temperature; and the second sensor is substantially at the temperature of the fluid; and a microcontroller containing firmware, wherein: the microcontroller calculates the first current; the microcontroller calculates the first and the second resistances; the microcontroller provides a control signal that sets the first current based on at least one of the first current, the first resistance, and the second resistance; and the microcontroller provides an output signal that is related to the flow property of the fluid based on at least one of the first current, the first resistance, and the second resistance.