• Proceedings of the KSME Conference
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• 2003.11a
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• pp.729-734
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• 2003

This paper reports the characteristics of the three dimensional turbulent flow in the rectangular-sectioned 180 degree bends by Hot-wire anemometer. Grande and Kool proposed a cooling law for the measurements of the flow through the narrow passage. The authors noticed that the calibration coefficients of original method are not constant and fairly sensitive to the flow approaching angle. Measured voltages are converted to three velocity and six Reynolds stress components using the modified method in which the coefficients are treated as a function of approaching angle.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.183-196
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• 1997

Gas flow field within the cylinder which is called a tumble flow is important factor in improving lean combustion stability. In this study, steady state flow tests were performed to quantify tumble ratio of flowfields generated by a tumble intensifying valve(TIV). In addition, velocity and fluctuation profiles in an intake port and flowfields in th cylinder were inspected using a hotwire anemometer and a laser light sheet method with various TIV configurations. These experimental results show that installated TIV has a great effect on flow field distribution in an intake port and test effects enhance a tumble flow in the cylinder.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.273-279
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• 2014

In this paper, wind tunnel tests of a scaled wind turbine have been performed to investigate the effects of turbulent intensity of oncoming flow on turbine wake field. The scaled turbine model was carefully designed to satisfy the similarity conditions. The wind velocities and turbulent intensities were measured using hotwire anemometer in order to compare with existing wake model. It was found from the tests that the existing wake models well fit with test results at turbulent flow rather than at uniform flow. Finally modified wake model has been proposed based on the measured data.

• International Journal of Fluid Machinery and Systems
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• v.7 no.2
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• pp.60-67
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• 2014

In order to clarify the effect of inlet bellmouth size of semi-opened type axial fan on its performance and flow fields around rotor, fan test and flow field measurements using hotwire anemometer were carried out for 6 kinds of bellmouth size. As results of fan test, the shaft power curve hardly changed, even if the bellmouth size changed. On the other hand, the pressure-rise near best efficiency point became small with the bellmouth size decreasing. Therefore, the value of maximum efficiency became small as the bellmouth size decreased. As results of flow field measurements at fan inlet, the main flow region with large meridional velocity existed near blade tip when the bellmouth size was large. As bellmouth size became smaller, the meridional velocity at fan inlet became smaller and the one at outside of blade tip became larger. As results of flow field measurements at fan outlet, the main flow region existed near rotor hub side.