Physical quantity measurement system

A physical quantity measurement system comprising:

• a flow channel through which gas mixtures including hydrogen and water vapor flow;
• a pair of ultrasonic transducers arranged to transmit and receive an ultrasonic wave and cause the ultrasonic wave to propagate across a flow of the gas mixtures through the flow channel;
• a pressure sensor configured to measure a pressure of the gas mixtures;
• a temperature sensor configured to measure a temperature of the gas mixtures;
• a humidity sensor configured to measure a humidity of the gas mixtures;
• a concentration measurer configured to measure a water vapor concentration as a concentration of the water vapor with respect to the gas mixtures and a gas concentration as a concentration of a gas included in the gas mixtures and different from the water vapor;
• and
• a flow rate measurer configured to measure a flow rate of the gas mixtures in the flow channel and also measure a flow rate of the gas using the flow rate of the gas mixtures,
• the concentration measurer being configured to:
• calculate the water vapor concentration using the pressure of the gas mixtures that has been measured by the pressure sensor, the humidity thereof that has been measured by the humidity sensor, and the temperature thereof that has been measured by the temperature sensor;
• and
• calculate the gas concentration using the water vapor concentration, a propagation time of the ultrasonic wave obtained by causing the pair of ultrasonic transducers to transmit and receive the ultrasonic wave, and the temperature that has been measured by the temperature sensor,
• the flow rate measurer being configured to calculate the flow rate of the gas mixtures using the pressure of the gas mixtures, the water vapor concentration, the gas concentration, and a flow coefficient, and
• the flow coefficient being a value based on a kinematic viscosity of the gas mixtures.

A physical quantity measurement system comprising:

• a flow channel through which gas mixtures including hydrogen and water vapor flow;
• a pair of ultrasonic transducers arranged to transmit and receive an ultrasonic wave and cause the ultrasonic wave to propagate across a flow of the gas mixtures through the flow channel;
• a concentration measurer configured to measure a water vapor concentration as a concentration of the water vapor with respect to the gas mixtures and a gas concentration as a concentration of a gas included in the gas mixtures and different from the water vapor;
• and
• a flow rate measurer configured to measure a flow rate of the gas mixtures in the flow channel and also measure a flow rate of the gas using the flow rate of the gas mixtures, the concentration measurer being configured to:
• calculate the water vapor concentration using the pressure of the gas mixtures, the humidity of the gas mixtures, and the temperature of the gas mixtures;
• and
• calculate the gas concentration using the water vapor concentration, a propagation time of the ultrasonic wave obtained by causing the pair of ultrasonic transducers to transmit and receive the ultrasonic wave, and the temperature of the gas mixtures,
• the flow rate measurer being configured to calculate the flow rate of the gas mixtures using the pressure of the gas mixtures, the water vapor concentration, the gas concentration, and a flow coefficient, and
• the flow coefficient being a value based on a kinematic viscosity of the gas mixtures.