Abstract
This paper presents analysis of steady flow passing through
a porous body in 3D, representing a steady current passing
through a space-frame offshore structure such as an offshore
jacket or a compliant tower. A porous body is used as a proxy
for a space-frame structure to model the effect of current blockage,
which may be interpreted as a global flow and force reduction
relative to the standard Morison drag formulation due
to the presence of the structure as a distributed obstacle. Both
uniform and sheared approach flows are simulated with CFD in
OpenFOAM for a porous body with uniformly distributed resistance.
The behaviour of the blockage due to both types of flow
are compared and contrasted using flow visualisation to illustrate
the interaction of the flow with the body and the evolution
of the resultant wake downstream of the body. The numerical
results are compared with the actuator disc model for uniform
flow due to [8] and the actuator disc model for sheared flow due
to [1]. A porous body with non-uniform vertically distributed
resistance is also considered, and the difference in the flow interaction
relative to body with uniform resistance is analysed
and discussed. The analysis provides the framework for applications
for wind loading on offshore structures such as a spaceframe
during load-out and transportation on a barge, as well as
numerical comparisons for an extension of the [1] model to an
actuator disc with non-uniform resistance.
a porous body in 3D, representing a steady current passing
through a space-frame offshore structure such as an offshore
jacket or a compliant tower. A porous body is used as a proxy
for a space-frame structure to model the effect of current blockage,
which may be interpreted as a global flow and force reduction
relative to the standard Morison drag formulation due
to the presence of the structure as a distributed obstacle. Both
uniform and sheared approach flows are simulated with CFD in
OpenFOAM for a porous body with uniformly distributed resistance.
The behaviour of the blockage due to both types of flow
are compared and contrasted using flow visualisation to illustrate
the interaction of the flow with the body and the evolution
of the resultant wake downstream of the body. The numerical
results are compared with the actuator disc model for uniform
flow due to [8] and the actuator disc model for sheared flow due
to [1]. A porous body with non-uniform vertically distributed
resistance is also considered, and the difference in the flow interaction
relative to body with uniform resistance is analysed
and discussed. The analysis provides the framework for applications
for wind loading on offshore structures such as a spaceframe
during load-out and transportation on a barge, as well as
numerical comparisons for an extension of the [1] model to an
actuator disc with non-uniform resistance.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 20th Australasian Fluid Mechanics Conference |
| Editors | Greg Ivey, Nicole Jones, Tongming Zhou |
| Publisher | Australasian Fluid Mechanics Society |
| Number of pages | 4 |
| ISBN (Electronic) | 9781740523776 |
| ISBN (Print) | 978-1-74052-377-6 |
| Publication status | Published - 2016 |
| Event | Australasian Fluid Mechanics Conference - , Australia Duration: 1 Jan 2011 → … |
Publication series
| Name | Proceedings of the 20th Australasian Fluid Mechanics Conference, AFMC 2016 |
|---|
Conference
| Conference | Australasian Fluid Mechanics Conference |
|---|---|
| Country/Territory | Australia |
| Period | 1/01/11 → … |