[ABSTRAK
Aliran PAS dibuat oleh Pekeris, Accad, dan Shkoller pada tahun 1973 sewaktumelakukan studi tentang model aliran yang dapat membangkitkan proses dinamo.Ternyata aliran PAS yang membangkitkan proses dinamo merupakan aliranBeltrami. Berdasarkan definisi helicity yang dikemukakan oleh Moffatt, aliranBeltrami memiliki helicity yang besar. Pada studi ini kita hitung seberapa besarhelicity aliran Beltrami tersebut. Untuk membandingkan besar helicity Beltramidengan helicity aliran yang lain maka kita hitung pula helicity salah satu alirannon Beltrami, yaitu aliran Quasi PAS. Hasilnya menunjukkan bahwa helicityaliran PAS lebih tinggi dari pada helicity aliran Quasi PAS.

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ABSTRACT
PAS flow created by Pekeris, Accad, and Shkoller in 1973 while conducting astudy on the flow model which can generate a dynamo process. Apparently thatPAS flow which generates dynamo process is a Beltrami flow. Based on thedefinition of helicity proposed by Moffatt, Beltrami flow has a large helicity. Inthis study we calculate how much the magnitude helicity of Beltrami flow. Tocompare the magnitude helicity of Beltrami flow with another flow, we alsocalculate helicity of a non Beltrami flow, that is Quasi PAS . The results show thatthe magnitude helicity of PAS flow is higher than the magnitude helicity of QuasiPAS flow ., PAS flow created by Pekeris, Accad, and Shkoller in 1973 while conducting astudy on the flow model which can generate a dynamo process. Apparently thatPAS flow which generates dynamo process is a Beltrami flow. Based on thedefinition of helicity proposed by Moffatt, Beltrami flow has a large helicity. Inthis study we calculate how much the magnitude helicity of Beltrami flow. Tocompare the magnitude helicity of Beltrami flow with another flow, we alsocalculate helicity of a non Beltrami flow, that is Quasi PAS . The results show thatthe magnitude helicity of PAS flow is higher than the magnitude helicity of QuasiPAS flow .]