DIFRAKSI GELOMBANG MELALUI BREAKWATER AMBANG RENDAH HALF CYLINDER
Jurusan Teknik Sipil Universitas Jenderal Soedirman
Indonesia
Departemen Teknik Sipil Universitas Diponegoro
Indonesia
Departemen Teknik Sipil dan Lingkungan Universitas Gadjah Mada
Indonesia
Departemen Teknik Sipil Universitas Diponegoro
Indonesia
Abstract
Gelombang datang akan mengalami difraksi saat melewati sebuah struktur yang relatif besar. Gelombang difraksi akibat breakwater ambang rendah half cylinder akan dihamburkan secara radial arah normalnya berupa gelombang hambur (scatter). Penelitian ini dilakukan untuk mengetahui kinerja breakwater ambang rendah half cylinder berdasarkan nilai koefesien hambur (scatter) gelombang (Ks) yang terjadi. Analisis potensial gelombang dilakukan untuk menyelesaikan persamaan pengatur aliran secara analitik menggunakan potensial kecepatan sebagai variabel dasar dengan menerapkan kondisi syarat batas yang ada. Hasil analitik kemudian diverifikasi menggunakan metode numerik. Hasil penelitian menunjukan bahwa koefesien scatter (Ks) breakwater ambang rendah half cylinder akan meningkat jika periode gelombang (T) dan nilai parameter a/h (a = jari-jari half cylinder, h = kedalaman air) bertambah besar. Nilai koefesien scatter (Ks) akan bernilai maksimum jika nilai ka 2 (k = wave number). Hasil verifikasi menunjukan bahwa metode analitik dan numerik menggunakan potensial kecepatan sebagai variabel dasar mendekati hasil yang sama jika nilai a/h ≤ 0,50.
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