Moisture & Trace Gas Sensor (MA)

Measurement of humidity and the amount of gas impurities in the humid air network.

blockType: AcausalFoundation.MoistAir.Sensors.MoistureAndTraceGas

Path in the library:

/Physical Modeling/Fundamental/Moist Air/Sensors/Moisture & Trace Gas Sensor (MA)

Description

Block Moisture & Trace Gas Sensor (MA) It measures humidity, the number of water droplets and gas impurities in the humid air network. There is no mass or energy flow through the sensor.

Ports W, Tw, D and G display the measurement results on port A of humidity, temperature according to a wet thermometer, the mass ratio of water droplets and the amount of gas impurities, respectively. The Tw port is used if for the parameter Measured humidity specification the value is set Wet-bulb temperature.

The sensor readings correspond to humidity and the amount of gas impurities in front of the measured node. For example, if the port A of the block is Moisture & Trace Gas Sensor (MA) connected to the node between pipe 1 and pipe 2 and humid air flows from pipe 1 into pipe 2, the humidity and the amount of gas impurities measured at port A characterize the volume of humid air in pipe 1. If the air flow then changes direction and flows from pipe 2 to pipe 1, then the humidity and the amount of gas impurities measured at port A characterize the volume of moist air in pipe 2. If the humidity and the amount of gas impurities in the two volumes of humid air are different, then the measured values change when the flow direction changes. If two or more updrafts merge in a node, the measurement of humidity and the amount of gas impurities in the node represents a weighted average based on the ideal mixing of the streams.

Ports

Output

# D — mass ratio of water droplets to moist air
scalar

Details

Signal output port for measuring the mass ratio of water droplets and moist air.

Dependencies

To use this port, check the box Water droplets.

Data types	`Float64`
Complex numbers support	No

# Tw — The temperature of the wet thermometer
scalar

Details

The signal output port for measuring the temperature readings of a wet thermometer that characterizes humidity.

Dependencies

To use this port, check the box Humidity and set for the parameter Measured humidity specification meaning Wet-bulb temperature.

Data types	`Float64`
Complex numbers support	No

# W — humidity
scalar

Details

Signal output port for humidity measurement. The measurement method is set by the parameter Measured humidity specification.

Dependencies

To use this port, check the box Humidity and set for the parameter Measured humidity specification one of the following values:

Relative humidity;
Specific humidity;
Mole fraction;
Humidity ratio.

Data types	`Float64`
Complex numbers support	No

# G — the level of gas impurities
scalar

Details

Signal output port for measuring the amount of gas impurities. The measurement method is set by the parameter Measured trace gas specification.

Dependencies

To use this port, check the box Trace gas.

Data types	`Float64`
Complex numbers support	No

Conserving

# A — sensor input
humid air

Details

The humid air port corresponds to the sensor inlet. Connect this port to the humid air network node where you want to measure humidity and the amount of gas impurities.

Program usage name

port

Parameters

Main

# Measured trace gas specification — method of measuring the amount of gas impurities
Mass fraction | Mole fraction

Details

Sets the measurement method:

Mass fraction ― the signal on port G is equal to the mass fraction of gas impurities.
Mole fraction ― the signal on port G is equal to a molar fraction of the gas impurities.

Values	`Mass fraction` \| `Mole fraction`
Default value	`Mass fraction`
Program usage name	`trace_gas_type`
Evaluatable	No

# Water droplets — turning on the output port for measuring water droplets

Details

When this option is selected, the output port D is activated, which allows you to measure the mass ratio of water droplets to moist air.

Default value	`false (switched off)`
Program usage name	`measure_droplets`
Evaluatable	No

# Measured humidity specification — humidity measurement method
Relative humidity | Specific humidity | Mole fraction | Humidity ratio | Wet-bulb temperature

Details

Sets the measurement method:

Relative humidity ― the signal on port W is equal to relative humidity.
Specific humidity ― the signal on port W is equal to the specific humidity.
Mole fraction ― the signal on port W is equal to a molar fraction of water vapor.
Humidity ratio ― the signal on port W is equal to the water vapor content.
Wet-bulb temperature ― the signal on the Tw port is equal to the temperature of a wet thermometer.

Values	`Relative humidity` \| `Specific humidity` \| `Mole fraction` \| `Humidity ratio` \| `Wet-bulb temperature`
Default value	`Relative humidity`
Program usage name	`moisture_type`
Evaluatable	No

# Trace gas — switching on the output port for measuring the amount of gas impurities

Details

When this option is selected, the output port G is enabled, which allows you to measure the value set by the parameter value. Measured trace gas specification.

Default value	`false (switched off)`
Program usage name	`measure_trace_gas`
Evaluatable	No

# Humidity — enabling the output port for humidity measurement

Details

When this option is selected, the output port W or Tw is enabled, which allows you to measure the value set by the parameter value. Measured humidity specification.

Default value	`true (switched on)`
Program usage name	`measure_humidity`
Evaluatable	No