• Wind and Structures
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• v.30 no.2
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• pp.199-210
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• 2020

Building wind pressure coefficient transiting test is a new method to test the building wind pressure coefficient by using the wind generated by a moving vehicle, which is susceptible to natural wind and other factors. In this paper, the Commonwealth Advisory Aeronautical Research Council standard model with a scale ratio of 1:300 is used as the test object, and the wind pressure coefficient transiting test is repeated under different natural wind conditions to study the influence of natural wind. Natural wind is measured by an ultrasonic anemometer at a fixed location. All building wind pressure coefficient transiting tests meet the test conditions, and the vehicle's driving speed is 72 km/h. The mean wind pressure coefficient, the fluctuating wind pressure coefficient, and the correlation coefficient of wind pressure are used to describe the influence of natural wind on the building wind pressure coefficient transiting test qualitatively and quantitatively. Some rules, which can also help subsequent transiting tests, are also summarized.

• New & Renewable Energy
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• v.7 no.4
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• pp.42-49
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• 2011

The objective of this paper is to suggest a new method of a wind turbine performance test. The performance test of a wind turbine is generally carried out in a wind tunnel. The test needs not only a high-accuracy measuring system but also durable structure to withstand high speed turbine rotation and wind flow. Therefore, we tried turbine performance test using a towing tank to improve stability and reliability. Because a turbine rotates more slowly and generates more torque in the water than in the wind tunnel under similarity conditions. In this study, we developed turbine performance test systems and verified the turbine test method using a towing tank through comparing results of the wind tunnel and the towing tank test.

• Wind and Structures
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• v.28 no.3
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• pp.155-170
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• 2019

This paper presents a novel test method for the galloping of iced conductor using wind generated by a moving vehicle which can produce relative wind field. The theoretical formula of transiting test is developed based on theoretical derivation and field test. The test devices of transiting test method for aerodynamic coefficient and galloping of an iced conductor are designed and assembled, respectively. The test method is then used to measure the aerodynamic coefficient and galloping of iced conductor which has been performed in the relevant literatures. Experimental results reveal that the theoretical formula of transiting test method for aerodynamic coefficient of iced conductor is accurate. Moreover, the driving wind speed measured by Pitot tube pressure sensors, as well as the lift and drag forces measured by dynamometer in the transiting test are stable and accurate. Vehicle vibration slightly influences the aerodynamic coefficients of the transiting test during driving in ideal conditions. Results of transiting test show that the tendencies of the aerodynamic coefficient curve are generally consistent with those of the wind tunnel tests in related studies. Meanwhile, the galloping is fairly consistent with that obtained through the wind tunnel test in the related literature. These studies validate the feasibility and effectiveness of the transiting test method. The present study on the transiting test method provides a novel testing method for research on the wind-resistance of iced conductor.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.321-325
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• 2006

Because strong wind is one of the few forces that, although considered in container crane design, still cause significant damage, a container crane was tested to investigate wind load characteristic in uniform flows. So, this study measured an external point pressure at the each members of a container crane according to a wind direction and a shape of members in a wind-tunnel test. The result of this test was compared to those of computation fluid dynamics using a CFX 10. The scale of a container crane model for wind tunnel test applied similarity scales to consider the size of the wind tunnel test section and the boundary condition for CFD is like wind tunnel test.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.35.2-35.2
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• 2011

A wind turbine power performance test is very important to wind turbine manufacturers because a wind farm developer or planner must want to define power performance characteristics and reliability of new wind turbines. Based on the IEC 61400-12-1, A wind turbine test site has to be nicely installed at flat terrain for testing. We are developing the wind power system which is IEC wind class IIa model with rated power of 3MW. KEPCO's Gochang power testing center was considered as candidates to build the test site without site calibration. This paper aims to verify the validity of the test site by using implement site assessment result that was based on IEC 61400-12-1.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.5-8
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• 2005

This paper aims to introduce the Daegwallyeong wind turbine test site which is the first official wind turbine test site in Korea. The current status of test site, the characteristics, the projects performed and future plan of this test site are described. The results of wind condition measurements and monitoring system established by the Kangwon National University are presented. The importance of field test is also commented.

• Wind and Structures
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• v.16 no.2
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• pp.137-156
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• 2013

A wind tunnel test of a scaled-down model and field measurement were effective methods for elucidating the aerodynamic behavior of a chimney under a wind load. Therefore, the relationship between the results of the wind tunnel test and the field measurement had to be determined. Accordingly, the set-up and testing method in the wind tunnel had to be modified from the field measurement to simulate the real behavior of a chimney under the wind flow with a larger Reynolds number. It enabled the results of the wind tunnel tests to be correlated with the field measurement. The model surface roughness and different turbulence intensity flows were added to the test. The simulated results of the wind tunnel test agreed with the full-scale measurements in the mean surface pressure distribution behavior.

• New & Renewable Energy
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• v.16 no.4
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• pp.23-32
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• 2020

The wind turbine gearbox has the longest downtime among other major turbine components such as blades, generators, and main bearings. Therefore, gearbox manufacturers conduct rig tests to evaluate conformity in terms of design and function. Rig tests, however, have limited similarity compared with atmospheric wind turbine operating conditions. Rig test conditions are thoroughly controlled and maintained by testers and the component certificates of gearboxes issued through the test cannot fulfill wind farm operator's requirements. Hence, certification bodies such as DNV-GL and UL require a mandatory gearbox field test report for type certification. The Korea Energy Agency (KEA) also introduced gearbox field test as a part of the KS type certificate in 2016, although it is optional . In this paper, gearbox field test procedures and requirements are introduced, and the first domestic application case of the test is reported. The field test was conducted with a 1.5 MW wind turbine gearbox located in Jeju as the test object.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.42-46
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• 2005

In spite of fast growing of prediction codes, there is still not negligible uncertainty in their results. This uncertainty affects on the turbine structural design and power production prediction. With the growing size of wind turbine, reducing this uncertainty is becoming one of critical issues for high performance and efficient wind turbine design. In this respect, there are international efforts to evaluate and tune prediction codes of wind turbine. As the reference data for this purpose, field test data is not appropriate because of its uncontrollable wind characteristics and its inherent uncertainty. Wind tunnel can provide controllable wind. For this reason, NREL has done the full scale test of the 10m turbine at NASA-Ames. With this reference data, a blind comparison has been done with participation of 18 organizations with 19 modeling tools. The results were not favorable. In Europe, a similar project is going on. Nine organizations from five countries are participating in the MEXICO project to do full scale wind tunnel tests and calculation with prediction codes. In this study. these two projects were reviewed in respect of wind tunnel test and its contribution. As a conclusion, it is suggested that scale model wind tunnel tests can be a complementary tool to calculation codes which were evaluated worse than expected.

• New & Renewable Energy
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• v.4 no.2
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• pp.87-93
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• 2008

Wind tunnel test for the 12% scaled model of NREL Phase VI wind turbine was conducted in KARI low speed wind tunnel for $2006{\sim}2007$. The 1st and 2nd test was designed to find out the wind tunnel test method for the blade manufacturing accuracy and surface treatment method by using the composite and aluminum blades. And the 3rd test was designed to study the scale effect. The chord extension method which was used for Bo-105 40% scaled model was adapted for scale effect correction. Test results shows that the chord extension method works well for the torque slope but the maximum torque for scaled model is about 8% below than the real scale model. New correction method to correct this offset was proposed.