WIND TUNNEL MODEL TEST ON THE PROPERTIES OF WIND PRESSURE ON ROOFING ELEMENTS MODELS IN SEPARATED AND REATTACHED FLOW : Research on the wind load on roofing elements to strong wind (Part 1)

In this paper, the current drag of a barge-shaped floating liquefied natural gas (FLNG) vessel was studied. Three model tests were performed — a wind tunnel model test, a submerged double-body tow test and a surface tow test. Computational fluid dynamics (CFD) simulations were carried out to gain further insights into the test results. During testing, the tow speed was kept low to avoid surface waves. When the current heading was around the beam current direction, the transverse drag coefficient measured from the wind tunnel test was significantly lower than those of the submerged tow and surface tow tests. The submerged tow and the surface tow provided similar drag coefficients. Results presented in this paper indicated that the difference between the wind tunnel test and the tow tests was caused by the wind tunnel boundary layer effect on the incoming wind profile and formation of a recirculation zone on the upstream side of the model, with a possible additional contribution from the wind tunnel floor constraint on the flow in the wake. Such effects are not accounted for with the simple corrections based on flow velocity reduction in the wind tunnel boundary layer. When conducting future wind tunnel model tests for barge-shaped FLNG hulls, one should consider the potential under-measurement of the transverse drag. In this paper, details of the FLNG model, test setup, test quality assurance (QA), measurement and CFD simulation results are presented, as well as discussions and recommendations for model testing.

Download Full-text

Physical Modeling and Simplification of FPSO Topsides Module in Wind Tunnel Model Tests

10.1115/omae2021-63459 ◽

2021 ◽

Author(s):

Zhenjia (Jerry) Huang ◽

Hyun Joe Kim

Keyword(s):

Quality Assurance ◽

Wind Tunnel ◽

Physical Model ◽

Model Test ◽

Physical Modeling ◽

Model Tests ◽

Model Construction ◽

Wind Tunnel Model ◽

Tunnel Model ◽

Modeling Practices

Abstract To evaluate wind load on offshore structures, such as FPSO’s, wind tunnel model test is a common industry practice. Configuration of topsides structures and equipment can be very complex, and it is a practical challenge to model all the structural details for wind tunnel model tests. Sometimes, there may be significant modifications to the topsides over FPSO operation life cycle and there may not be detailed topsides drawing for wind tunnel to use in physical model construction. In practice, wind tunnel laboratories have to simplify physical topsides models. They also use metal meshes to cover the topsides modules to compensate for the force reduction due to the simplification. In order to help establish physical modeling practices of wind tunnel model test, we performed extensive tests using a single topsides module. The original topsides module without simplification and mesh was tested first. Then, two simplifications were adopted in the physical model construction. The module was covered with and without metal mesh of different porosities. Thorough test quality assurance (QA) and quality control (QC) were performed to ensure data quality. Test setup, quality assurance (QA) and results are presented in the paper. The results can be used not only for appropriate physical modeling practices of complex topsides modules, but also for validation of numerical predictions such as Computational Fluid Dynamics (CFD), as well as empirical formulas.

Download Full-text

Wind loads on a moving vehicle-bridge deck system by wind-tunnel model test

Wind and Structures ◽

10.12989/was.2014.19.2.145 ◽

2014 ◽

Vol 19 (2) ◽

pp. 145-167 ◽

Cited By ~ 24

Author(s):

Yongle Li ◽

Peng Hu ◽

You-Lin Xu ◽

Mingjin Zhang ◽

Haili Liao

Keyword(s):

Wind Tunnel ◽

Model Test ◽

Bridge Deck ◽

Wind Loads ◽

Wind Tunnel Model ◽

Moving Vehicle ◽

Tunnel Model

Download Full-text

Development of a six-axis force/moment sensor for wind tunnel model test

Measurement Science and Technology ◽

10.1088/0957-0233/24/11/115101 ◽

2013 ◽

Vol 24 (11) ◽

pp. 115101 ◽

Cited By ~ 4

Author(s):

Wenjun Wang

Keyword(s):

Wind Tunnel ◽

Model Test ◽

Wind Tunnel Model ◽

Tunnel Model ◽

Force Moment

Download Full-text

Wind Tunnel Tests for Wind Pressure Distribution on Gable Roof Buildings

The Scientific World JOURNAL ◽

10.1155/2013/396936 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Xiao-kun Jing ◽

Yuan-qi Li

Keyword(s):

Wind Tunnel ◽

Pressure Field ◽

Wind Load ◽

Wind Pressure ◽

Strong Wind ◽

Load Path ◽

Wind Tunnel Tests ◽

Pressure Distributions ◽

Gable Roof ◽

Aspect Ratios

Gable roof buildings are widely used in industrial buildings. Based on wind tunnel tests with rigid models, wind pressure distributions on gable roof buildings with different aspect ratios were measured simultaneously. Some characteristics of the measured wind pressure field on the surfaces of the models were analyzed, including mean wind pressure, fluctuating wind pressure, peak negative wind pressure, and characteristics of proper orthogonal decomposition results of the measured wind pressure field. The results show that extremely high local suctions often occur in the leading edges of longitudinal wall and windward roof, roof corner, and roof ridge which are the severe damaged locations under strong wind. The aspect ratio of building has a certain effect on the mean wind pressure coefficients, and the effect relates to wind attack angle. Compared with experimental results, the region division of roof corner and roof ridge from AIJ2004 is more reasonable than those from CECS102:2002 and MBMA2006.The contributions of the first several eigenvectors to the overall wind pressure distributions become much bigger. The investigation can offer some basic understanding for estimating wind load distribution on gable roof buildings and facilitate wind-resistant design of cladding components and their connections considering wind load path.

Download Full-text