Water metering device and methods for water consumption apportionment

A method for determining fluid consumption comprising:

• actuating, by a non-invasive fluid meter mounted on a pipe, a first ultrasonic transducer to emit a first ultrasonic signal and a second ultrasonic transducer to emit a second ultrasonic signal;
• detecting, by the non-invasive fluid meter, a total time of flight based on the first ultrasonic signal and the second ultrasonic signal;
• determining, by the non-invasive fluid meter via a temperature sensor, an ambient temperature of an environment surrounding the non-invasive fluid meter;
• estimating, by the non-invasive fluid meter, a temperature of fluid within the pipe based on the total time of flight and the ambient temperature;
• determining, by the non-invasive fluid meter, a volumetric flow rate coefficient and an offset by taking into account environmental factors for the non-invasive fluid meter at the environment surrounding the non-invasive fluid meter, wherein the volumetric flow rate coefficient and the offset are each based on at least one pipe characteristic, the ambient temperature of the environment, or the temperature of the fluid;
• and
• determining, by the non-invasive fluid meter, a volumetric flow rate based on the volumetric flow rate coefficient, the offset, and a time of flight difference between the first ultrasonic signal and the second ultrasonic signal.