VELOCITY FIELDS OF EXTERNAL AND BOUNDARY-LAYER FLOWS DURING RUN-UP PHASE OF A SOLITARY WAVE TRAVELING ON A SLOPING BEACH
Published In: 5TH INTERNATIONAL CONFERENCE ON ADVANCES IN CIVIL, STRUCTURAL AND MECHANICAL ENGINEERING
Author(s): HAN-CHANG LING , MING-JER KAO , WEI-YING WONG
Abstract: The characteristics of velocity fields of the external and boundary layer flo ws during run - up motion of a non - breaking solitary wave propagating over a 1:3 sloping beach are explored experiment ally. Flow visualization technique (FVT) of particle trajectory photography and high - speed particle image velocimetry (HSPIV) were employed to qualitatively observe and quantitatively measure the macro - viewed external and micro - viewed boundary layer flow fields . The experiments were conducted in wave flume equipped with a wave maker being triggered by a precise servo - motor . The incident wave - h eight to water - depth ratio s , H 0 / h 0 , is equal to 0. 363 . The slope of the sloping beach model is fixed at 1 :3. Profoundly d istinct characteristics of flow fields around the flow demarcation curve s, as observed respectively from the macro - view ed external flow and the micro - viewed boundary layer flow , are first interpreted, together with eluci dation of the flow reversal ex
- Publication Date: 03-Sep-2017
- DOI: 10.15224/978-1-63248-132-0-58
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AN EXPERIMENTAL STUDY OF FLUID DYNAMICS OF STALL DELAY ON THE BLADE OF A HORIZONTAL-AXIS WIND TURBINE*
Published In: 5TH INTERNATIONAL CONFERENCE ON ADVANCES IN CIVIL, STRUCTURAL AND MECHANICAL ENGINEERING
Author(s): SHAOQIONG YANG , YANHUA WU , ZHANQI TANG
Abstract: Fluid dynamics of the stall delay phenomenon is studied experimentally in this work on a horizontal - axis wind turbine (HAWT) blade. The 3D - printed blade is produced from a downscaled model of a 5kW HAWT. Its rotational motion in the test section of wind tunnel is precisely controlled by a programmable motor. Both mean static pressures and dynamic pressur es are measured on the suction surface at the spanwise location of 0.25R of the blade at two different global tip speed ratios (TSR) of 3 and 5. The TSR of 3 corresponds to a large angel of attack (AOA) at 30 degrees where the flow is fully separated. The other TSR of 5 corresponds to a smaller AOA of 15 degrees. Planar time - resolved particle image velocimetry measurements at 0.25R for the above two TSRs were performed to study the dynamics of the separated flows when the stall is delayed on the rotating bl ade. The Reynolds numbers at these two TSRs, based on the half chord length of the blade and its relative velocity, are 8683
- Publication Date: 03-Sep-2017
- DOI: 10.15224/978-1-63248-132-0-59
- Views: 0
- Downloads: 0