Multi-chamber rate-of-change system for gas flow verification

1. A multi-chamber rate-of-change flow meter system, the system comprising:

a collection of N chambers;

means for drawing a gas into or out of the collection of N chambers;

at least one temperature sensor to measure temperature of the gas;

N pressure sensors, each one of the N pressure sensors is coupled to a corresponding one of the N chambers;

means for redistributing the gas among the chambers, the means for redistributing the gas among the chambers includes a plurality of flow restrictors; and

a measurement module coupled to the pressure sensors to obtain a rate of change of pressure in each of the chambers due to the redistribution of the gas and calculate a sum of gas flows into or out of each of the N chambers to obtain a flow rate of the gas flowing into or out of the collection of N chambers based upon the temperature and the rate of change of pressure in each of the chambers.

2. The multi-chamber rate-of-change flow meter system of claim 1 , wherein the means for drawing a gas into or out of the collection of N chambers includes:

an upstream valve;

a downstream valve;

a vacuum pump; and

the measurement module is configured to:

close the upstream valve, open the downstream valve, and evacuate the N chambers with the vacuum pump; and

close the downstream valve and open the upstream valve to draw the gas into the collection of N chambers.

3. The multi-chamber rate-of-change flow meter system of claim 2 , including:

a diversion duct coupled between an inlet of the collection of N chambers and an outlet of the collection of N chambers via a diversion valve;

wherein the measurement module is configured to:

open the diversion valve while the upstream valve is closed to allow gas to flow through the diversion duct to create a non-zero flow before the downstream is closed; and

close the diversion valve in connection with the opening the upstream valve to draw the gas into the collection of N chambers.

4. The multi-chamber rate-of-change flow meter system of claim 3 , wherein the diversion valve and the upstream valve are integrated into a three-way valve.

5. The multi-chamber rate-of-change flow meter system of claim 1 , wherein the means for drawing a gas into or out of the collection of N chambers includes:

an upstream valve;

a downstream valve;

a vacuum pump; and

the measurement module configured to:

open the upstream valve to draw the gas into the collection of N chambers at a first flow rate, open the downstream valve to draw the gas out of the collection of N chambers at a second flow rate that exceeds the first flow rate to evacuate the N chambers with the vacuum pump; and

close the downstream valve to draw the gas into the collection of N chambers.

6. The multi-chamber rate-of-change flow meter system of claim 1 , wherein the at least one temperature sensor comprises

N temperature sensors, each one of the N temperature sensors is coupled to a corresponding one of the N chambers; and

wherein the measurement module is coupled to the temperature sensors to obtain a temperature of each of the N chambers and calculate a flow rate of the gas flowing into or out of the collection of N chambers based upon the rate of change of pressure in each of the chambers and the temperature of each of the N chambers.

7. The multi-chamber rate-of-change flow meter system of claim 1 , wherein the means for redistributing the gas among the chambers includes conduit between each chamber and one other chamber.

8. The multi-chamber rate-of-change flow meter system of claim 1 , wherein the means for drawing a gas into or out of the collection of N chambers includes:

an upstream valve;

a downstream valve;

a gas pressurizer; and

the measurement module configured to:

open the upstream valve, close the downstream valve, and pressurize the collection of N chambers with the gas pressurizer; and

open the downstream valve and close the upstream valve to draw the gas out of the collection of N chambers.

9. A method for measuring a flow rate of a gas with a mulit-chamber rate-of-change flow meter system, the method comprising:

drawing a gas into or out of the collection of N chambers;

obtaining readings from N pressure sensors, each one of the N pressure sensors is coupled to a corresponding one of the N chambers;

obtaining a measure of a temperature of the gas;

restricting, without stopping, gas flow between chambers via a plurality of flow restrictors, to redistribute the gas among the N chambers; and

calculating a sum of gas flows into or out of each of the N chambers to obtain a flow rate of the gas flowing into or out of the collection of N chambers based upon the temperature and the rate of change of pressure in each of the chambers.

10. The method of claim 9 , wherein drawing the gas into or out of the collection of N chambers includes:

evacuating the N chambers; and

opening an upstream valve to draw the gas into the collection of N chambers.

11. The method of claim 10 , including diverting gas around the collection of N chambers to create a non-zero flow before drawing a gas into or out of the collection of N chambers.

12. The method of claim 9 , wherein drawing the gas into or out of the collection of the N chambers includes:

drawing the gas into the collection of N chambers at a first flow rate while drawing the gas out of the collection of the N chambers at a second flow rate that exceeds the first flow rate to create a lower pressure in the N chambers than exists outside of the N chambers; and

ceasing to draw gas out of the collection of the N chambers when the lower pressure reaches a threshold.