SensorVLE L3 T
Created Dienstag 31 Januar 2017
A real temperature sensor.
1. Purpose
Create a temperature measurement signal locally and use it for visualisation and control purposes. The unit of the signal may be adjusted by setting unitOption appropriately. The model includes heat transfer to the sheath of the thermocouple element and thermal masses. Optionally, the heat conduction of the sensor sheath to the pipe wall can be considered.
2. Level of Detail, Physical Effects Considered and Physical Insight
2.1 Level of Detail
Referring to Brunnemann et al. [1], this model refers to the level of detail L3 because the system is modelled with the use of balance equations.
2.2 Physical Effects Considered
- Heat transfer to sheath of sensor
- Thermal mass of sheath
- Optionally: Thermal mass of pipe wall which is affected by (ideal) heat conduction from sensor sheath
2.3 Level of Insight
Heat Transfer
- Basics:ControlVolumes:Fundamentals:HeatTransport:Generic HT:Adiabat L2
- Basics:ControlVolumes:Fundamentals:HeatTransport:Generic HT:IdealHeatTransfer L2
- Basics:ControlVolumes:Fundamentals:HeatTransport:Generic HT:Constant L2
- Basics:ControlVolumes:Fundamentals:HeatTransport:Generic HT:CharLine L2
3. Limits of Validity
- only simple heat transfer models
- no heat transfer to component's wall
- no influence of sensor on pressure loss
4. Governing Equations
This model is composed by instantiation of the following classes:
- Basics:ControlVolumes:FluidVolumes:VolumeVLE L2 volume of the volume in the component
- Basics:ControlVolumes:SolidVolumes:ThinWall L4 sheath of sensor
5. Usage
- Prefer the usage of this sensor over text based, "virtual" measurements e.g. via MSL's RealExpression as it is less error prone.
- The visualised value will turn red if its value is below 0°C (end of validity of water media model).
- Adjust heat transfer model and sheath material of the sensor
- If the option considerHeatConduction==true the parameter length determines the length of the pipe wall which is affected by heat conduction. Heat conduction is assumed as ideal in axial direction. Furthermore, temperatures at the heat ports of sensor sheath and inner pipe wall are equal.
6. Revisions
- 31.01.2017 - v 1.2.0 initial implementation - F.Gottelt, T.Hoppe, XRG Simulation GmbH
- 20.02.2018 - v 1.3.0 added option to consider heat conduction - T.Hoppe, XRG Simulation GmbH