Sains Malaysiana 45(1)(2016): 99–107

Wind Tunnel Experimental Research on the Effect of Col Topography on Wind Environment

(Penyelidikan Eksperimen Terowong Angin ke atas Kesan Topografi Kol Alam Sekitar Angin)

LIU HUI*

Department of Civil Engineering, Sichuan College of Architectural Technology

618000 Sichuan, China

Diserahkan: 17 Julai 2014/Diterima: 2 November 2014

ABSTRACT

Investigation of meteorological disasters caused by small-scale topography shows that flashover due to wind age yaw occurred quite often where col topography existed. Considering that the distribution pattern of wind profile at different locations of a col topography is not clear, this paper, with wind tunnel tests, studied the influenced of such topographic features of a col as hill slope and valley mouth width on the wind profile at different locations. The results of wind tunnel tests indicated that over-hill wind has a stronger effect on wind velocity correction coefficient than does valley wind, that compared to flat terrain wind velocity, the maximum speed-up amplitude of wind velocity at valley throat and hill summit reach 33 and 53%, respectively, apparently higher than 10% specified in Codes, that wind velocity at valley throat increases with the increase of hill slope and decreases with the increase of valley mouth width, that wind velocity in the valley basically does not go up when the slope of one hill side is smaller than 0.1 and that wind velocity at the same non-dimensional height of a 3D hill summit increases with the increase of hill height.

Keywords: Col; wind tunnel test; wind velocity correction coefficient

ABSTRACT

Kajian bencana meteorologi yang disebabkan oleh topografi berskala kecil menunjukkan bahawa lampau kilat kerana anginan rewang berlaku agak kerap dengan kol topografi wujud. Memandangkan bahawa pola taburan profil angin di lokasi yang berbeza daripada topografi kol tidak jelas, kertas kerja ini dengan ujian terowong angin, mengkaji pengaruh ciri-ciri seperti topografi kol sebagai cerun bukit dan lembah lebar mulut ke atas profil angin di lokasi yang berbeza. Keputusan ujian terowong angin menunjukkan bahawa angin lepas bukit mempunyai kesan yang kuat pada pekali pembetulan halaju angin daripada angin lembah atas dengan halaju angin rupa bumi rata, amplitud kelajuan sehingga maksimum halaju angin di lembah tekak dan puncak bukit masing-masing pada 33 dan 53%, nampaknya 10% lebih tinggi daripada yang dinyatakan dalam Kod, bahawa halaju angin di lembah tekak bertambah dengan peningkatan cerun bukit dan berkurang dengan peningkatan lebar mulut lembah, bahawa halaju angin di lembah itu pada dasarnya tidak naik apabila lereng bukit satu bahagian lebih kecil daripada 0.1 dan bahawa halaju angin pada ketinggian tanpa dimensi yang sama sidang kemuncak bukit 3D meningkat dengan peningkatan ketinggian bukit.

Kata kunci: Angin pekali pembetulan halaju; kol; ujian terowong angina

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*Pengarang untuk surat-menyurat; email: lyzliuhui@126.com