HollowCylinder
Created Tuesday 08 April 2014
This model defines the basic geometric parameters of a hollow cylinder.
1. Purpose of Model
The model is used to define the geometry of a cylindrical control volume of the level of detail L2
2. Physical Insight
The volume and heat transfer area of the block are calculated according to the following properties:
- Cylinder diameter
- Cylinder length
- Cylinder orientation
- Flow orientation
3. Limits of Validity
4. Nomenclature
5. Governing Equations
5.1 System Description and General Model Approach
This model defines geometrical properties of a hollow cylinder. The orientation of the cylinder can be set to "horizontal" or to "vertical" as can be seen in the following pictures. The model defines also the flowOrientation through the component. Thus, the hollow cylinder geometry is basically characterised by its length, diameter and the flow orientation.
5.2 Governing Model Equations
The volume is calculated via the standard equation for a cuboid in Eq. 1.
The frontal area of the cylinder is determined by Eq. 2 depending on the relation between geometrical and flow orientation
The cross sectional area of the hollow cylinder is equivalent to the frontal area.
Depending on the cylinder orientation the nominal horizontal area is computed via Eq.4
The vector of the heat transferring area is calculated depending on the flow orientation. For a hollow cylinder geometry surfaces are considered for the heat transfer.
The first entry is the lateral surface of the block determined by Eq. 5.1. The heat transfer area is calculated via:
Thus, it is assumed that the frontal area does not contribute to the total external surface.
The fillable height of the component is determined by
6. Remarks for Usage
Whenever the cylinder's volume or its cross section is zero or negative an assert will raise an error message. Additionally, z_in and z_out must be smaller than height_fill and greater equal than 0.
- A_cross > 0
- volume > 0
- z_in < height_fill
- z_out < height_fill
- z_in >= 0
- z_out >= 0
7. Validation
8. References
9. Version History
20.02.2012 - v01 - Initial implementation - Friedrich Gottelt, XRG Simulation GmbH
07.03.2016 - v1.1.0 - introduced assert for inlet outlet height outside the component - Friedrich Gottelt, XRG Simulation GmbH