could counteract the higher wind sp

could counteract the higher wind speed, and so the wind
speed was depressed until the end of the model. In this
condition, the air was prevented from suddenly speeding
up. The same occurred on the dimple and dome bionic
models. So the bottom pressure of the model did not
change sharply, and the pressure drag reduced.
(2) Non-smooth structures reduce the surface vorticity
Because of the non-smooth surface, the lateral migration
of the eddy was blocked; the air could extend
only streamwise along the model. The eddy growth was
disturbed, and the derivational velocity was also reduced.
Another reason, because of the non-smooth surface, the
growth of tiny fluid micelle was also prevented. So the
large moment of inertia induced by large fluid micelle
was prevented. The reduction of vorticity reduced the
dissipation of the eddy. So the pressure drag could also
be reduced.
(3) Non-smooth structures make momentum layer
thinner in the boundary
As well as the mechanisms above, the relationship
between momentum thickness and the drag coefficient
can also explain the results. It was believed that the
development of pressure drag relies on the effect between
the momentum thickness and the stress layer one
another before the bottom of the model. The bionic
structures made the momentum layer thinner, according
to the relationship between the drag coefficient and the
momentum thickness shown in Eq. (3,th e reduction of
the momentum thickness leads to drag reduction.
Acknowledgement
This project was supported by the National Natural
Science Foundation of China (Grant No.50635030), the
International Cooperation key Project of Ministry of
Science and Technology of China (Grant No.
2005DFA00850), The key project about ministry of
education of science and technology (Grant No. 105059)
the international cooperative of Jilin Province (Grant
No.20040703-I), and Specialized Research fund for the
Doctoral Program of higher Education (Grant No.
200501 83064).
The authors are grateful to Professor Julian Vincent
for the English check and decoration of this paper.
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Hasil (Bahasa Indonesia) 1:

bisa melawan angin kecepatan yang lebih tinggi, dan begitu anginkecepatan tertekan sampai akhir model. Dalam hal inikondisi, udara dicegah dari tiba-tiba mempercepatup. Sama terjadi pada lesung dan kubah bionikmodel. Jadi tekanan bawah model tidakmengubah tajam, dan drag tekanan berkurang.(2) bebas-halus struktur mengurangi vorticity permukaanKarena permukaan bebas-halus, migrasi lateraldari eddy diblokir; udara dapat memperpanjanghanya streamwise sepanjang model. Pertumbuhan eddyterganggu, dan kecepatan derivational juga berkurang.Alasan lain, karena permukaan bebas-halus,pertumbuhan kecil cairan Misel juga dicegah. Jadibesar Momen inersia disebabkan oleh besar cairan Miseldicegah. Pengurangan vorticity dikurangidisipasi eddy. Jadi drag tekanan bisa jugadikurangi.(3) bebas-halus struktur membuat momentum layertipis di perbatasanSerta mekanisme di atas, hubunganantara momentum ketebalan dan koefisien dragdapat juga menjelaskan hasil. Kononpembentukan tekanan tarik bergantung pada efek antaraketebalan momentum dan stres lapisan satulain sebelum bagian bawah model. Bionicstruktur lapisan momentum yang dibuat lebih tipis, menuruthubungan antara koefisien drag danketebalan momentum yang ditampilkan di EQ (3, th e penguranganketebalan momentum yang mengarah pada pengurangan drag.PengakuanProyek ini didukung oleh alam NasionalScience Foundation Cina (Grant No.50635030),Kerjasama internasional kunci proyek KementerianIlmu pengetahuan dan teknologi (No. hibah2005DFA00850), kunci proyek tentang Departemenpendidikan ilmu pengetahuan dan teknologi (hibah No. 105059)Koperasi internasional Provinsi Jilin (hibahNo.20040703-saya), dan dana penelitian khusus untukProgram Doktor pendidikan tinggi (No. hibah200501 83064).Penulis sangat berterima kasih kepada Profesor Julian Vincentuntuk Periksa Inggris dan hiasan kertas ini.ReferensiRen L Q, Tong J, Li J Q, Chen B C. tanah adhesi danbiomimetics komponen yang menarik tanah: review. Jurnalpenelitian teknik pertanian, 2001, 79, 239 -263.Miklosovic D S, Murray M M, E Howle L, ikan F E. terkemukatepi tuberkel penundaan kios pada paus humpback (Megapterasirip novaeangliae). Fisika cairan, 2004,16,39-42.Memenangkan S Y, Zhang Q, Ligrani P M perbandingan aliranstruktur di atas berlesung Pipit permukaan dengan lesung berbedakedalaman dalam saluran. Fisika cairan, 2005,17,045 105.Tong J, Ren L Q, Chen B C. geometris morfologiKonstitusi kimia dan wettability dari permukaan tubuhhewan tanah. Jurnal teknik pertanian internasional,1994,3,59-68.Lee S J, analisis bidang Lee S H. arus dari batas bergolaklapisan permukaan riblet. Percobaan dalam cairan, 2001, 30,153-166.Walsh M J. Riblets. Dalam: Bushnell D M, Hefner J N (eds).Kental pengurangan drag dalam lapisan batas. Kemajuan dalam Astronauticsdan Antariksa. AIAA, Washington, 1990, 123,203-262.J M Walsh, Penjual W L, McGinley C B. Riblet pengurangan dragpada kondisi penerbangan. Jurnal Aircrafr, 1989,26, 570-575.Bechert D W, Bruse M, W Hage, van der Hoeven J G T,Percobaan G Hoppe pada mengurangi drag permukaan dan merekaoptimasi dengan geometri disesuaikan. Jurnal cairanMekanika, 1997,338,59-87.Bechert D W, Hoppe G, van der Hoeven J G T, Makris R.Saluran minyak Berlin untuk menyeret pengurangan penelitian. Percobaandalam cairan, 1992, 12,251-260.Bechert D W, Bruse M, Hage W. eksperimen dengantiga dimensi riblets sebagai model ideal kulit hiu.Percobaan dalam cairan, 2000,28,403-412.Viswanath P R. pesawat kental tarik pengurangan menggunakan riblets.Kemajuan ilmu kedirgantaraan, 2002,38,57 1-600.Bechert D W, Bruse M, W Hage, mekanika fluida Meyer R.permukaan biologis dan aplikasi teknologi mereka.Naturwissenschaften, 2000,87,157-171.Tian L M, Ren L Q, Han Z W, C. Bang S eksperimen mengenaipengurangan permukaan kasar bionik drag dalam kecepatan yang rendahterowongan angin. Jurnal teknik bionik, 2005, 2, 15 -24.