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Measurement Selector (MA)

Measure pressure, temperature, humidity, and trace gas levels in moist air internal volumes

  • Library:
  • Simscape / Foundation Library / Moist Air / Sensors

  • Measurement Selector (MA) block

Description

The Measurement Selector (MA) block lets you access the pressure, temperature, moisture level, and trace gas level measurements inside a block with a finite moist air volume. There is no mass or energy flow through the sensor.

Blocks with a finite moist air volume contain an internal node, which represents the moist air volume inside the component. (For a complete list of these blocks, see Blocks with Moist Air Volume.) Regular sensors cannot connect to this internal node. Therefore, each of the blocks with a finite moist air volume has a physical signal output port F, which outputs a vector signal containing the pressure (in Pa), temperature (in K), moisture level, and trace gas level measurements inside the component. For more information, see Measuring Moisture and Trace Gas Levels.

Use the Measurement Selector (MA) block to unpack the vector signal and reassign units to pressure and temperature values. Connect the input port F of the Measurement Selector (MA) block to the physical signal output port F of a block with finite internal moist air volume to access the data.

Connect the output ports of the Measurement Selector (MA) block to PS-Simulink Converter blocks to transform the output physical signals into Simulink® signals, for example, for plotting or additional data processing. Use the Output signal unit parameter of the PS-Simulink Converter blocks connected to ports P and T to reassign units to pressure and temperature values, respectively.

Ports

Input

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Connect this port to the physical signal output port F of a block with finite internal moist air volume to access the data. Blocks with a finite moist air volume have a physical signal output port F, which outputs a vector signal containing the pressure (in Pa), temperature (in K), moisture level, and trace gas level measurements inside the component. Use the Measurement Selector (MA) block to unpack this vector signal.

Output

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Physical signal output port for pressure measurement.

Physical signal output port for temperature measurement.

Physical signal output port for moisture level measurement. To select the quantity you want to measure, use the Measured moisture specification parameter.

Physical signal output port for trace gas level measurement. To select the quantity you want to measure, use the Measured trace gas specification parameter.

Parameters

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Select the property to measure:

  • Relative humidity ― Physical signal port W reports the relative humidity.

  • Specific humidity ― Physical signal port W reports the specific humidity.

  • Mole fraction ― Physical signal port W reports the water vapor mole fraction.

  • Humidity ratio ― Physical signal port W reports the humidity ratio.

Select the property to measure:

  • Mass fraction ― Physical signal port G reports the trace gas mass fraction.

  • Mole fraction ― Physical signal port G reports the trace gas mole fraction.

Model Examples

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Introduced in R2018a