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Thermodynamic Properties Sensor (MA)

Measure specific enthalpy, density, specific heat at constant pressure, and specific entropy of air mixture

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

  • Thermodynamic Properties Sensor (MA) block

Description

The Thermodynamic Properties Sensor (MA) block represents an ideal sensor that measures specific enthalpy, density, specific heat at constant pressure, and specific entropy of the air mixture in a moist air network. There is no mass or energy flow through the sensor.

The block measures these thermodynamic properties at the node connected to port A.

You have a choice of outputting these measurements normalized by the mass of the whole air mixture, or by the mass of dry air and trace gas only. The second option is consistent with the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) standards.

The specific entropy reference value, used for sensor calibration, is 0 for each constituent of the moist mixture at atmospheric pressure and atmospheric temperature. Atmospheric pressure and atmospheric temperature are defined by the parameters of the Moist Air Properties (MA) block connected to the circuit.

Ports

Output

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Physical signal output port for measuring the specific enthalpy of the air mixture.

Physical signal output port for measuring the density of the air mixture.

Physical signal output port for measuring the specific heat of the air mixture at constant pressure.

Physical signal output port for measuring the specific entropy of the air mixture.

Conserving

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Moist air conserving port. Connect this port to the node in the moist air network where you want to measure the thermodynamic properties.

Parameters

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Select whether measurements are normalized by the mass of the whole air mixture, or by the mass of dry air and trace gas only:

  • Unit mass of moist air mixture — For each thermodynamic property, the measured mass of that property in a moist air volume is divided my the mass of the most air mixture.

  • Unit mass of dry air and trace gas — For each thermodynamic property, the measured mass of that property in a moist air volume is divided my the mass of dry air and trace gas (leaving out the mass of the water vapor). Use this option when you need to compare your measurements with ASHRAE figures and charts.

Extended Capabilities

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

Introduced in R2018a