System and method for measuring flow

A system of determining a flow rate of a fluid comprising:

• a constant volume chamber;
• a sonic nozzle in fluid communication with the constant volume chamber;
• one or more valves configured to direct a flow of a fluid to the constant volume chamber and the sonic nozzle;
• sensors configured to read one or parameters of the fluid;
• and
• a controller coupled to the sensors configured to receive measurements from the sensors, the controller comprising:
• a processor;
• a memory accessible by the processor, the memory storing a set of computer instructions comprising instructions executable by the processor to:
• in a first mode of operation, calculate the flow rate as fluid accumulates in the constant volume chamber;
• and
• in a second mode of operation, calculate the flow rate as the fluid flows through the sonic nozzle;
• and
• switch between the first mode of operation and the second mode of operation after a delay to allow the constant volume chamber to equilibrate.

A method of determining a flow rate of a fluid comprising:

• for a first mode of operation, calculating the flow rate as fluid accumulates in a constant volume chamber for a first range of flow rates;
• and
• for a second mode of operation, calculating the flow rate as the fluid flows through the sonic nozzle;
• delaying to allow the constant volume chamber to equilibrate;
• and
• switching between the first mode of operation and the second mode of operation.

A system of determining a flow rate of a fluid comprising:

• a constant volume chamber;
• a sonic nozzle in fluid communication with the constant volume chamber;
• one or more valves configured to direct a flow of a fluid to the constant volume chamber and the sonic nozzle;
• sensors configured to read one or parameters of the fluid;
• and
• a controller coupled to the sensors configured to receive measurements from the sensors, the controller comprising:
• a processor;
• a memory accessible by the processor, the memory storing a set of computer instructions comprising instructions executable by the processor to:
• in a first mode of operation, calculate the flow rate as fluid accumulates in the constant volume chamber;
• and
• in a second mode of operation, calculate the flow rate as the fluid flows through the sonic nozzle;
• switch between the first mode of operation and the second mode of operation;
• calculate the flow rate according to the first mode of operation in an overlap range of flow rates;
• and
• calculate a cross sectional area of the sonic nozzle based on the flow rate calculated according to the first mode of operation.

A system of determining a flow rate of a fluid comprising:

• a constant volume chamber;
• a sonic nozzle in fluid communication with the constant volume chamber;
• one or more valves configured to direct a flow of a fluid to the constant volume chamber and the sonic nozzle;
• sensors configured to read one or parameters of the fluid;
• and
• a controller coupled to the sensors configured to receive measurements from the sensors, the controller comprising:
• a processor;
• a memory accessible by the processor, the memory storing a set of computer instructions comprising instructions executable by the processor to:
• in a first mode of operation, calculate the flow rate as fluid accumulates in the constant volume chamber;
• and
• in a second mode of operation, calculate the flow rate as the fluid flows through the sonic nozzle;
• switch between the first mode of operation and the second mode of operation;
• calculate the flow rate according to the first mode of operation in an overlap range;
• and
• calculate a heat capacity ratio of the fluid based on the flow rate calculated according to the first mode of operation.

A method of determining a flow rate of a fluid comprising:

• for a first mode of operation, calculating the flow rate as fluid accumulates in a constant volume chamber for a first range of flow rates;
• and
• for a second mode of operation, calculating the flow rate as the fluid flows through the sonic nozzle;
• switching between the first mode of operation and the second mode of operation;
• calculating the flow rate according to the first mode of operation in an overlap range of flow rates;
• and
• calculating a cross sectional area of the sonic nozzle based on the flow rate calculated according to the first mode of operation.

A method of determining a flow rate of a fluid comprising:

• for a first mode of operation, calculating the flow rate as fluid accumulates in a constant volume chamber for a first range of flow rates;
• and
• for a second mode of operation, calculating the flow rate as the fluid flows through the sonic nozzle;
• switching between the first mode of operation and the second mode of operation
• calculating the flow rate according to the first mode of operation in an overlap range;
• and
• calculating a heat capacity ratio of the fluid based on a the flow rate calculated according to the first mode of operation.