 

Building-Cube Method ࠍ↪޿ߚࠛࡦࠫࡦ࠽࠮࡞ࠗࡦ࡟࠶࠻߆ࠄߩ㛍㖸વ᠞⸃ᨆ
⑔ፉ⵨㚍 㧘ᄢᨋ⨃ 㧘૒‫ᧁޘ‬ᄢテ 㧘ਛᯅ๺ඳ 1᧲ർᄢቇᄢቇ㒮Ꮏቇ⎇ⓥ⑼㧘2 ᧲ർᄢቇᵹ૕⑼ቇ⎇ⓥᚲ
3㊄ᴛᎿᬺᄢቇᎿቇㇱ㧘4 ቝቮ⥶ⓨ⎇ⓥ㐿⊒ᯏ᭴ ᰴ਎ઍߩᢙ୯ᵹ૕⸃ᨆᚻᴺߣߒߡឭ᩺ߐࠇߚ Building-Cube Method ࠍ↪޿ߡ㧘⥶ⓨಽ㊁ࠍਛᔃߦታ↪⊛ߥᄢⷙᮨࠪࡒࡘ࡟࡯࡚ࠪࡦߩขࠅ⚵ߺࠍㅴ߼ߡ޿ࠆ㧚ᧄⓂߢߪ Building-Cube Method ߩ೑ὐࠍ↢߆ߒߡ㧘⥶ⓨᯏࠛࡦࠫࡦ߆ࠄ⊒↢ߔࠆ㛍㖸ߩ⸃ᨆࠍⴕ޿㧘ߘߩ⚿ᨐࠍ␜ߔ㧚㛍㖸ߩ⸃ᨆߦߪ㜞๟ᵄࠍ⸃௝ߔࠆߚ߼ߦ⤘ᄢߥᩰሶὐᢙ߇ᔅⷐߣߥࠅ⸘▚⽶⩄߇㜞ߊߥࠆ௑ะߦ޽ࠆ߇㧘ࡌࠢ࠻࡞ൻߐࠇߚ Building-Cube Method ࠰࡞ࡃ࡯ߣࠨࠗࡃ࡯ࠨࠗࠛࡦࠬ࠮ࡦ࠲࡯ߩ⸘▚ᯏⅣႺߩ೑
↪ߦࠃࠅᄢⷙᮨⓨജ㖸㗀⸃ᨆࠍታ⃻ߒߚ㧚㧝㧚 ✜⸒
ㄭᐕ㧘㜞ࡃࠗࡄࠬᲧࠛࡦࠫࡦߩណ↪ߥߤߦࠃߞߡ⥶ⓨᯏ߆ࠄ⊒↢ߔࠆ㛍㖸ߪૐਅߒߡ޿ࠆ㧚ߘߩ৻ᣇߢ㧘ⓨ᷼ઃㄭߩ㛍㖸ⷙ೙ߪએ೨ߦჇߒߡ෩ߒߊߥߞߡ߅ࠅ㧘⥶ⓨᯏ߆ࠄ⊒↢ߔࠆ㛍㖸ߩᦝߥࠆૐ㛍㖸ൻߦะߌߚ⎇ⓥߪࠃࠅ㊀ⷐߦߥߞߡ޿ࠆ㧚⥶ⓨᯏ߆ࠄߩ㛍㖸ߪࠛࡦࠫࡦ㛍㖸㧘ᯏ૕㛍㖸ߦಽߌࠆߎߣ߇ߢ߈㧘ࠛࡦࠫࡦ㛍㖸ߦߪࡈࠔࡦ㛍㖸㧘ࠫࠚ࠶࠻㛍㖸߇޽ࠆ㧚ࠛࡦࠫࡦ߇ࡈ࡞ࠬࡠ࠶࠻࡞ߩ⁁ᘒߢ޽ࠆ㔌㒽ᤨߦߪࡈࠔࡦ㛍㖸㧘ࠫࠚ࠶࠻㛍㖸߇ᡰ㈩⊛ߢ޽ࠅ㧘⌕㒽ᤨߦߪࠬ࡜࠶࠻߿ዷ㐿ਛߩࡈ࡜࠶ࡊߥߤߩ㜞឴ജⵝ⟎㧘⣉ߥߤߩ㒠⌕ⵝ⟎߆ࠄ⊒↢ߔࠆᯏ૕㛍㖸ߩഀว߇Ⴧടߔࠆߣ޿߁௑ะ߇㗼⪺ߦ⷗ࠄࠇࠆ㧚 ৻⥸⊛ߥⓨജ㖸㗀႐ߩᢙ୯⸃ᨆߪ㧘ᦨೋߦ㖸Ḯ๟ㄝߩᵹࠇ႐ࠍ࠽ࡆࠛ࡮ࠬ࠻࡯ࠢࠬᣇ⒟ᑼߢ⸃߈㧘ߘߩ⚿ᨐ߆ࠄ Lighthill ߩ㖸㗀ቇ⊛㘃ផߦၮߠ޿ߡ㆙ᣇ㖸႐ࠍ੍᷹ߔࠆߣ޿߁ಽ㔌ᣇᴺ߇↪޿ࠄࠇࠆ㧚࿕૕Ⴚ⇇ߩᓇ㗀ࠍ⠨ᘦߒߚ Curle ߩᑼࠍ↪޿ߚ⸃ᨆߪ⸘▚ࠦࠬ࠻ߩὐ߆ࠄఝࠇߡ߅ࠅ㧘ᐢߊ↪޿ࠄࠇߡ޿ࠆ[1]㧚ߒ߆ߒߎߩᚻᴺߦߪ㧘ᵹࠇ႐ߩ৻᭽ᕈ㧘㖸Ḯߩࠦࡦࡄࠢ࠻ᕈࠍ઒ቯߒߡ޿ࠆߣ޿߁໧㗴ὐ߽޽ࠆ㧚ߎࠇߦኻߒߡ㧘࿶❗ᕈࠝࠗ࡜࡯ᣇ⒟ᑼࠍ㖸ᵄᚑಽߦኻߒߡ✢ᒻൻߒߚ✢ᒻࠝࠗ࡜࡯ᣇ⒟ᑼ (Linearized Euler Equation, LEE)ࠍ↪޿ߚ⸃ᨆᴺ߇ᵈ⋡ߐࠇߡ߅ࠅ㧘ゲኻ⒓ࠛࡦࠫࡦᒻ⁁߆ࠄߩ㛍㖸⸃ᨆߦ↪޿ࠄࠇߡ޿ࠆ[2]㧚LEE ߦࠃࠆ⸃ᨆߪ㧘⸃ᨆኻ⽎߇৻᭽ߥᵹࠇ႐ߩ㗔ၞߦ㒢ቯߐࠇߕ㧘‛૕ㄭறߢߩ࿁᛬߿෻኿߽ขࠅ౉ࠇߚ㛍㖸ߩ੍᷹ߦㆡߒߡ޿ࠆ㧚ታ〣⊛ߥⶄ㔀ᒻ⁁ࠍขࠅᛒ߁ߎߣࠍ⠨߃ࠆߣ㧘ᓥ᧪ߩ᭴ㅧᩰሶ㧘㕖᭴ㅧᩰሶࠍ↪޿ߚᚻᴺߢߪߘࠇߙࠇ⺖㗴߇޽ࠆ㧚᭴ㅧᩰሶࠍ↪޿ߚ⸃ᨆߢߪ㧘‛૕ᒻ⁁ߦᴪߞߚᩰሶࠍ㈩⟎ߔࠆߚ߼ߦ‛૕ㆡวᕈߦఝࠇߡ޿ࠆ߇㧘⥶ⓨᯏోᯏᒻ⁁߿ߐࠄߦⶄ㔀ߥᒻ⁁๟ࠅߦᩰሶࠍ↢ᚑߔࠆߦߪ⤘ᄢߥᤨ㑆ࠍⷐߒ㧘ታ↪⊛ߢߪߥ޿㧚㕖᭴ㅧᩰሶߦࠃࠆ⸃ᨆߪ㧘ⶄ㔀ᒻ⁁ࠍᛒ߁ߩߦఝࠇߡ޿ࠆ߇㧘৻⥸ߦⓨ㑆♖ᐲ߇ૐߊ㧘㜞ᰴ♖ᐲߩ⸃ᨆᚻᴺߢ޽ࠆ Discontinuous Galerkin Method (DGM)ߢߪᩰሶὐᒰ
ߚࠅߩ⸘▚ࠦࠬ࠻߇ᄢ߈ߊߥࠆ㧚ߘߎߢᧄ⎇ⓥߢߪ㧘න⚐ߥ⋥੤ᩰሶࠍ↪޿ߚ⸃ᨆߦ⌕⋡ߒߚ㧚⋥੤ᩰሶߦࠃࠆ⸃ᨆߢߪ㧘ⓨ㑆ࠍ⋥੤ߦಽഀߔࠆߣ޿߁◲ଢߐߩߚ߼ߦⶄ㔀ᒻ⁁ࠍኈᤃߦᛒ߁ߎߣ߇ߢ߈ࠆ㧚߹ߚ㧘ⓨ㑆㜞ᰴ♖ᐲൻ߇ኈᤃ㧘⸘▚ല₸߇㜞޿ߣ޿߁೑ὐ߽޽ࠆ㧚⋥੤ᩰሶࠍ↪޿ߚ⸃ᨆߪ㧘㓏Ბ⁁ㄭૃߦࠃࠆᓇ㗀ࠍߢ߈ࠆߛߌዊߐߊߔࠆߚ߼ߦ㧘‛૕ㄭறߦ⚦߆޿ᩰሶࠍᔅⷐߣߔࠆ㧚ߒ߆ߒ㧘╬㑆㓒ᩰሶ߿ਇ╬㑆㓒ᩰሶߦ߅޿ߡ㜞ኒᐲߥᩰሶࠍ↪޿ࠆߣ㧘⚦߆޿ᩰሶὐ߇ਇᔅⷐߥ㆙ᣇߦ߹ߢ㈩⟎ߐࠇࠆ㧚ߘߎߢᧄ⎇ⓥߢߪ㧘ਛᯅߩឭ᩺ߒߚ⋥੤Ⓧߺ਄ߍᴺ (Building-Cube Method, BCM [3])ߦࠃࠅ⸃ᨆࠍⴕ߁㧚‛૕߆ࠄ㔌ࠇߚ㗔ၞߦ߅޿ߡߪᔅⷐචಽߥኒᐲߩᩰሶࠍ↪޿ࠆ৻ᣇߢ㧘‛૕ㄭறߦߪࠃࠅ⚦߆ߊ⚦ಽൻߐࠇߚᩰሶࠍ↪޿ࠆߎߣߢ㧘ᩰሶ  ὐᢙߩჇടࠍᛥ߃ߥ߇ࠄ㓏Ბ⁁ㄭૃߦࠃࠆ⺋Ꮕࠍᛥ೙ߢ߈ࠆ㧚ߒ߆ߒߥ߇ࠄ㧘ዪᚲ⚦ಽൻᩰሶߩߺߢߪ㧘‛૕ㄭறࠍߤࠇ߶ߤ⚦߆ߊ⚦ಽൻߒߡ߽㧘⴫㕙ߦ㑐ߒߡߪ㓏Ბ⁁ㄭૃߩᓇ㗀ߪᱷߞߡߒ߹߁ߚ߼㧘ࠃࠅ㜞♖ᐲߥო㕙ߩขࠅᛒ޿߇ᦸ߹ߒ޿㧚ട߃ߡ㧘㓁⸃ᴺߦࠃࠆ⸃ᨆߢߪᦨዊᩰሶ᏷ߦࠃߞߡᤨ㑆ࠬ࠹࠶ࡊ߇᳿ቯߒߡߒ߹߁㧚ߎࠇࠄߩߎߣࠃࠅ㧘♖ᐲ⦟޿⸃ᨆࠍታ↪⊛ߥ⚦߆ߐߢⴕ߁ᔅⷐ߇޽ࠅ㧘ᧄ⎇ⓥߢߪၒ߼ㄟߺႺ⇇ᴺ(Immersed Boundary Method, IBM)ߦࠃࠆ‛૕⴫⃻ࠍ↪
޿ࠆ㧚 ᧄⓂߢߪ㧘BCM ߩࠕ࡞ࠧ࡝࠭ࡓߦၮߠߊ LEE ࠰࡞ࡃ࡯ࠍ↪޿ߡ⥶ⓨᯏࠛࡦࠫࡦࠍᮨߒߚ
Generic Inlet ᒻ⁁߆ࠄߩ㛍㖸વ᠞ߩ⸃ᨆࠍⴕ߁㧚Ყセߩኻ⽎ߪ 50m ㆙ᣇߦ߅ߌࠆ Sound Pressure
Level (SPL)ಽᏓߢ޽ࠅ㧘㆙ᣇߢߩᜰะᕈߩផቯߪ Ffowcs Williams-Hawkings (FW-H)ᴺߦࠃࠅⴕ߁㧚⸘▚㗔ၞౝߩ Point Per Wavelength (PPW)ߩᄌൻ㧘FW-H 㕙ߩ૏⟎ߦࠃࠆᄌൻ㧘࠽࠮࡞๟ࠅߩᩰሶࠍ⚦ಽൻߒߚ㓙ߩᄌൻࠍߘࠇߙࠇᲧセߔࠆߎߣߦࠃࠅ㧘ᧄ⸘▚ᚻᴺߩ㛍㖸⸃ᨆߦ߅ߌࠆ᦭ലᕈࠍᬌ⸽ߔࠆ㧚㧞㧚 ⸘▚ᚻᴺ㧞㧚㧝 ✢ᒻൻࠝࠗ࡜࡯ᣇ⒟ᑼ(Linearized Euler Equations, LEE)㛍㖸વ᠞ߩᡰ㈩ᣇ⒟ᑼߢ޽ࠆ LEE ࠍᑼ(1)㧘(2)ߦ␜ߔ㧚LEE ߪ㧘࿶❗ᕈࠝࠗ࡜࡯ᣇ⒟ᑼߩ‛ℂᄌᢙ Q ࠍ Q=Q0+Q’ߩࠃ߁ߦᵹࠇ႐ߩᐔဋᚑಽ Q0 ߣᄌേᚑಽ Q’ߦಽ⸃ߔࠆߎߣߢᓧࠄࠇࠆ㧚(1)㧘(2)ߦ߅޿ߡ H ߪᐔဋᚑಽߩⓨ㑆ᄌേߦߟ޿ߡߩ㗄ߢ޽ࠅ㧘S ߪ㖸Ḯ㗄ߢ޽ࠆ㧚߹ߚ㧘 ߪᲧᾲᲧߢ޽ࠆ㧚⸘▚ߩ㓙ߪ㧘ᵹࠇ႐ߩᐔဋᚑಽ Q0 ߣ㖸Ḯ㗄 S ࠍਈ߃㧘ᄌേᚑಽ Q’ߩᤨ㑆⊒ዷࠍ⸘▚ߔࠆ㧚
wQ ' wE wF wGHwtwx wy wzª U0 º«u »« 0»« v0 » , E« »« w0 »«¬ p0 »¼(1)Sª U 0 u ' U ' u0 º«»« u0 u ' p ' »U0 »««», Fu0 v '«»«»u0 w '«»«¬u0 p ' J p0 u '»¼

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w0 v '«»« w w ' p ' »0«U0 »«»«¬ w0 p ' J p0 w '»¼(2)!"#$%&'&()*+&,-./01234567

㧞㧚㧞 ⸘▚ࠕ࡞ࠧ࡝࠭ࡓ
ᢙ୯⸘▚ߪ BCM ߩ⸘▚ࠕ࡞ࠧ࡝࠭ࡓߦࠃࠅⴕࠊࠇࠆ[3]㧚BCM ߢߪ⸘▚㗔ၞో૕ߢ╬㑆㓒⋥੤ᩰሶࠍ↪޿ࠆߎߣߢ㧘೨ಣℂ࡮ᢙ୯⸘▚࡮ᓟಣℂߩߔߴߡߩᲑ㓏ߢಣℂࠍන⚐ൻߢ߈ࠆ㧚⸘▚ᩰሶߩ↢ᚑߪ㧘࿑ 1(a)ߩࠃ߁ߦ㧘⸘▚㗔ၞࠍ Cube ߣ๭߫ࠇࠆ 2n ୚ߩᄢ߈ߐߩ㆑޿ࠍᜬߟᱜᣇᒻ㗔ၞߦಽഀߒ㧘ᰴߦ㧘Cube ࠍ࿑ 1(b)ߩࠃ߁ߦฦゲᣇะหᢙߩᩰሶὐ(Cell)ߢಽഀߔࠆ㧚߹ߚ㧘ߘࠇߙࠇߩ Cube ߪ㓞ࠅว߁ Cube ߣ㊀ߥࠅวߞߚ overlap Cell ࠍ 3 ߟᜬߞߡ߅ࠅ㧘overlap Cell ߦ‛ℂ㊂ࠍ⵬㑆ߔࠆߎߣߢ㓞ࠅว߁ Cube ߣᖱႎ੤឵ࠍⴕ޿ߥ߇ࠄ⸘▚ࠍㅴ߼ࠆ㧚࿑ 2 ߦ LEE ࠰࡞ࡃ࡯ߩ⸘▚ࠕ࡞ࠧ࡝࠭ࡓࠍ␜ߔ㧚⸘▚ߩೋᦼߢ⸘▚ᩰሶ߿‛૕ᒻ⁁࠺࡯࠲ࠍ౉ജߒ㧘೨ಣℂࠍⴕ߁㧚ᧄ⎇ⓥߢߪ Runge-Kutta ᴺߦࠃࠅᤨ㑆Ⓧಽࠍⴕ߁ߩߢ㧘ߘߩ෻ᓳ⸘▚ߩਛߢ㧘⸘▚㗔ၞࠍභ߼ࠆ Cubeౝߩ⸘▚ߪ OpenMP ߦࠃࠅਗ೉ߦⴕࠊࠇࠆ㧚BCM ߩ⸘▚ᩰሶߪ㧘ߔߴߡߩ Cube ߇หᢙߩ Cell ࠍ฽ࠎߢ޿ࠆߩߢ㧘ਗ೉⸘▚ߩ㓙ߦ⽶⩄ߩ஍ࠅ߇ߥߊਗ೉ൻല₸ߦఝࠇߡ޿ࠆ㧚Cube ߦ߅޿ߡ⸘▚ߔࠆౝኈߪએਅߢ޽ࠆ㧚
1.Cube Ⴚ⇇ߦ߅޿ߡ㓞ធߔࠆ Cube ߣߩᖱႎ੤឵
2.ᡰ㈩ᣇ⒟ᑼࠍ⸘▚3.Runge-Kutta ᴺߦ߅ߌࠆ઒ߩ‛ℂ㊂ Qsub ࠍᦝᣂ4.✭ⴣ㗔ၞߢ‛ℂ㊂ࠍᷫ⴮ⓨ㑆ᓸಽߪ 4 ᰴ♖ᐲߩ᦭㒢Ꮕಽࠬࠠ࡯ࡓߢ޽ࠆ Dispersion Relation Preserving (DRP)ࠬࠠ࡯ࡓ[4]ࠍ↪޿ࠆ㧚߹ߚ㧘⸘▚ߢ⊒↢ߔࠆ㕖‛ℂ⊛ߥᝄേࠍขࠅ㒰ߊߚ߼ߦ 4 ᰴ♖ᐲߩ Damper ࠍㆡ↪ߒߡ޿ࠆ㧚ᤨ㑆Ⓧಽߦߪ 6 Ბ 4 ᰴ♖ᐲߩ Low Dissipation Dispersion Runge-Kutta (LDDRK)[5]ࠍ↪޿ࠆ㧚
LEE ࠰࡞ࡃ࡯ߩ⸘▚ߢߪ㧘⊒↢ߒߚ㛍㖸ߪ⸘▚㗔ၞߩᄖㇱႺ⇇ߢ෻኿ߒߡߒ߹߁㧚ߘࠇࠍ㒐ߋߚ߼㧘ᧄ⎇ⓥߢߪᄖㇱႺ⇇ઃㄭߦ✭ⴣ㗔ၞࠍ⸳ቯߒ㧘✭ⴣ㗔ၞߢߪ buffer zone Ⴚ⇇᧦ઙ[6]ߦࠃࠅ‛ℂ㊂ࠍᷫ⴮ߐߖࠆ㧚&XEH&HOO2YHUODS&HOO(a) ⸘▚㗔ၞౝߩ Cube(b) Cube ߩ᭴ᚑ (1515Cell, 3 overlap Cells)࿑ 1 ੑᰴరߩ⸘▚ᩰሶߩ଀  
Q '( n )E , F , G, H , S

Q'sub(n)Q 'sub ( n )Q '( n 1)

࿑ 2 LEE ߩ⸘▚ࠕ࡞ࠧ࡝࠭ࡓ

㧞㧚㧟 ၒ߼ㄟߺႺ⇇ᴺ(Immersed Boundary Method, IBM) ᧄ⎇ⓥߢ↪޿ࠆ IBM ߪ ghost cell (GC)ߣ image point (IP)ࠍ↪޿ߚ߽ߩߢ޽ࠆ[7]㧚߹ߕ㧘‛૕ᒻ⁁ࠍ Stereo Lithography (STL)࠺࡯࠲ߣߒߡ౉ജߒ㧘ߘࠇࠍ↪޿ߡ⸘▚ Cell ߇‛૕ߩౝㇱ߆ᄖㇱ߆ࠍ್೎ߔࠆ㧚ߘߒߡ㧘‛૕ౝㇱߩ৻ጀ⋡ߩ Cell ࠍ GC ߣߒߡ↪޿ࠆ㧚ߘߒߡ㧘GC ߆ࠄ‛૕ု⋥ᣇะߦ㧘ᦨዊ Cell ߩ 1.5 ୚ߩ㐳ߐߩ૏⟎ߦ IP ࠍቯ⟵ߔࠆ㧚ߘߒߡ IP ߦ๟ࠅߩ Cell ߆ࠄ‛ℂ㊂ࠍ⵬㑆ߒ㧘IP ߢߩ୯ࠍ↪޿ߡ‛૕⴫㕙ߢṖࠅოႺ⇇᧦ઙࠍḩߚߔࠃ߁ߦ GC ߩ‛ℂ㊂ࠍ᳿ቯߔࠆ㧚IP ߳ߩ⵬㑆ࠍⴕ߁㓙㧘ਃᰴరߢߪ IP ࠍ࿐߻ 333 ߩ 27 ὐࠍ↪޿ߡㅒ〒㔌ട㊀ᴺߦࠃߞߡⴕ߁(࿑3)㧚

(a) GC ߩቯ⟵ߣ IP ߳ߩ⵬㑆        
࿑ 3 ၒ߼ㄟߺႺ⇇ᴺq1q4q7q2q5q8q3q6qIP q9(b) IP ߳ߩ⵬㑆㧞㧚㧠 Cube Ⴚ⇇ߢߩᖱႎ੤឵
ᄢ߈ߐߩ㆑߁ Cube ߩႺ⇇ߢߪᩰሶὐ߇❬߇ߞߡ޿ߥ޿ߚ߼ߦ㧘⵬㑆ߦࠃߞߡᖱႎ੤឵ࠍⴕ߁ᔅ
ⷐ߇޽ࠆ㧚ᧄ⎇ⓥߢߪ㜞ᰴߩᄙ㗄ᑼ⵬㑆ᴺߢ޽ࠆ࡜ࠣ࡜ࡦࠫࡘ⵬㑆ࠍ↪޿ߚ[8]㧚ߎࠇߪ㧘ᑼ(3)㧘












!

"#$%&'(')*+,'-./012345678

(4)ߦ␜ߔ〒㔌ߩ㊀ߺଥᢙࠍ↪޿ߡ⵬㑆ࠍⴕ߁߽ߩߢ޽ࠆ㧚
QOC¦Q

j ,k ,l w j ( xOC )wk ( yOC )wl ( zOC )(3)

j ,k ,lw j ( xOC )( xOC  xi )( yOC  yi )( zOC  zi ) (x  x ) , w ( y )  ( y  y ) , w (z )  (z  z )
iz j

jik

OCizkklOCi

i zll(4)i

Qj,k,l ߪࠬ࠹ࡦࠪ࡞ߢߩ‛ℂ㊂ߢ޽ࠆ㧚
wj(xOC)㧘wk(yOC)㧘
ߎߎߢ㧘
QOC ߪ overlap Cell ߢߩ‛ℂ㊂ߢ޽ࠅ㧘wl(zOC)ߪ overlap Cell ߳ߩ⵬㑆ߦ↪޿ࠆ㊀ߺଥᢙߢ޽ࠆ㧚߹ߚ㧘xOC㧘yOC㧘zOC ߪ overlap Cell ߩ x,y,zᐳᮡߢ޽ࠅ㧘xi㧘yi㧘zi ߪ⵬㑆ߦ↪޿ࠆࠬ࠹ࡦࠪ࡞ߩᐳᮡߢ޽ࠆ㧚࿑ 4 ߪੑᰴరߢߩ⵬㑆ߦ↪޿ࠆࠬ࠹ࡦࠪ࡞㈩⟎ࠍ␜ߒߡ޿ࠆ㧚࿑ 4(a)ߪዊߐ޿ Cube ߆ࠄᄢ߈޿Cube ߳ߩ⵬㑆ߦ↪޿ࠆࠬ࠹ࡦࠪ࡞ߢ޽ࠆ㧚Overlap Cell ߪ 1 ೉ߦኻߒߡ 3 ߟߢ޽ࠆ߇㧘࡞ࡦࠥ⃻⽎ࠍᛥ߃ࠆߚ߼㧘⵬㑆ߦ↪޿ࠆࠬ࠹ࡦࠪ࡞߇ኻ⒓ߣߥࠆࠃ߁ߦ Cube Ⴚ⇇ߦᦨ߽ㄭ޿ Cell ߪ 22ὐߢߩ⵬㑆㧘ߘߩઁ 2 ߟߪ 44 ὐߢߩ⵬㑆ࠍⴕ߁㧚࿑ 4(b)ߪᄢ߈޿ Cube ߆ࠄዊߐ޿ Cube ߳ߩ⵬㑆ߦ↪޿ࠆࠬ࠹ࡦࠪ࡞ߢ޽ࠆ㧚ߎߜࠄߪ overlap Cell 2 ೉ಽߩ⵬㑆ὐߦኻߒߡᄢ߈޿ Cube ߩ 33ὐߩหߓ Cell ߩ‛ℂ㊂ࠍ↪޿ߚ⵬㑆ࠍⴕ߁㧚(a) ዊߐ޿ Cube ߆ࠄᄢ߈޿ Cube ߳ߩ⵬㑆  (b) ᄢ߈޿ Cube ߆ࠄዊߐ޿ Cube ߳ߩ⵬㑆࿑ 4 ⵬㑆ߩ↪޿ࠆࠬ࠹ࡦࠪ࡞㈩⟎㧞㧚㧡 㖸Ḯߩ⸳ቯᣇᴺ ࡈࠔࡦ㛍㖸ߩ౉ജߪ Tyler ߣ Sofrin ߦࠃࠅឭ᩺ߐࠇߚ spinning mode ౉ജߦࠃࠅਈ߃ࠆ㧚ߎࠇߪ㧘ࡈࠔࡦ߿േ⠢࡮㕒⠢ߩ⋧੕ᐓᷤߦࠃߞߡ⊒↢ߔࠆ㛍㖸ࠍᮨߒߚ߽ߩߢ޽ࠅ㧘એਅߩᑼߦࠃߞߡ㖸࿶ᄌേࠍਈ߃ࠆ߽ߩߢ޽ࠆ㧚(5)p '( x, r ,T , t ) a[ J m (kr r )  c1Ym (kr r )]cos(kt  ka x  mT )ߎߎߢ㧘Jm, Ym ߪߘࠇߙࠇ m ᰴߩ╙ 1 ⒳㧘2 ⒳ߩ Bessel 㑐ᢙߢ޽ࠆ㧚ka ߪ axial wavenumber㧘kr ߪradial wavenumber ߢ޽ࠆ㧚kr ߩ n ᰴߩ⸃ߪએਅߩᑼߦ೰ოߩႺ⇇᧦ઙࠍਈ߃ࠆߎߣߦࠃࠅ᳞߹ࠆ㧚d [ J m ( router k r )] d [Ym ( rinner k r )] d [ J m ( rinner k r )] d [Ym ( router k r )]
drdrdrdr0ߎߎߢ㧘router㧘rinner ߪ࠳ࠢ࠻ߩౝඨᓘ㧘ᄖඨᓘߢ޽ࠆ㧚ka ߪએਅߩᑼ߆ࠄ⸘▚ߐࠇࠆ㧚(6) ka kr2 (1  M 2j ) ·k §¨¸Mr1
j¸
1  M 2j ¨k2©
¹

(7)ߎߎߢ㧘+ߪ౞ᩇᐳᮡߦ߅޿ߡᱜᣇะߦㅴ߻ᵄ㧘㧙ߪ⽶ᣇะߦㅴ߻ᵄࠍ⴫ߒߡ޿ࠆ㧚ଥᢙ c1 ߪએਅߩᑼߦࠃࠅ⸘▚ߐࠇࠆ㧚c1



(d / dr )[ J m (router kr )](d / dr )[Ym (router kr )](d / dr )[ J m (rinner kr )](d / dr )[Ym (rinner kr )](8)㧞㧚㧢 ㆙ᣇߢߩ㛍㖸ߩផቯᣇᴺ ᧄ⎇ⓥߢߪ Ffowcs Williams-Hawkings (FW-H)ᴺࠍ↪޿ߡ㆙ᣇ㖸႐ࠍផቯߔࠆ㧚FW-H ᴺߣߪ㧘ㄭறߩ㖸Ḯࠍ࿐߻㐽ᦛ㕙਄ߩ‛ℂ㊂࠺࡯࠲ߩᤨ㑆ᄌൻࠍ↪޿ߡ㧘㆙ᣇߢߩ‛ℂ㊂ߩᤨ㑆ᄌൻࠍផቯ
ߔࠆ⸘▚ᚻᴺߢ޽ࠆ㧚ߎߩ㐽ᦛ㕙ࠍ FW-H 㕙ߣ๭߱㧚㆙ᣇ႐ߩ㛍㖸ផቯߩߚ߼ߩ⸘▚ߩᵹࠇߪએਅߩࠃ߁ߦߥࠆ㧚߹ߕ㧘ࡈࠔࡦ㕙ߦ spinning mode ౉ജࠍਈ߃ࠆ㧚ߘߒߡ㧘LEE ߦࠃࠅㄭறߢߩ㛍㖸ߩવ᠞ࠍ⸃ᨆߔࠆ㧚ᦨᓟߦ FW-H ᴺߦࠃࠅ㆙ᣇߢߩ㛍㖸ߩવ᠞ࠍផቯߔࠆ㧚㧟㧚 Generic Inlet ๟ࠅߩ㛍㖸વ᠞⸃ᨆਃᰴరゲኻ⒓࠽࠮࡞ᒻ⁁ߢ޽ࠆ Generic Inlet ߆ࠄߩ㛍㖸વ᠞ࠍ⸃ᨆߒ㧘⸃ᨆࡄ࡜ࡔ࡯࠲ࠍᄌൻߐߖߚ႐วߩ㆙ᣇߦ߅ߌࠆ SPL ಽᏓࠍᲧセߔࠆ㧚߹ߚ㧘DGM ࠍ↪޿ߚᏒ⽼ߩ⸘▚࠰࡞ࡃ࡯ߢ޽ࠆ ACTRAN/DGM ߦࠃࠆ⸘▚⚿ᨐߣᲧセߔࠆߎߣߢ㧘ᧄᚻᴺߩ⸘▚♖ᐲࠍ⏕⹺ߔࠆ㧚⸘▚ኻ⽎ߣߥࠆ Generic Inlet ᒻ⁁ࠍ࿑ 5 ߦ␜ߔ㧚࿑ౝߩὐ✢ߪࡈࠔࡦ㕙ߩ૏⟎ߢ޽ࠆ㧚߹ߚ㧘㕍✢ߪ㖸㗀࡜ࠗ࠽࡯ߩ⸳⟎૏⟎ࠍ␜ߒߡ޿ࠆ߇㧘੹࿁ߩ⸃ᨆߢߪ↪޿ߥ޿㧚⸘▚㗔ၞߩේὐߪ࿑
5(a)ߩ z=0㧘y=0 ߩ૏⟎ߢ޽ࠅ㧘⸘▚㗔ၞߩᄢ߈ߐ߽࿑ 5(a)ߩ୯ࠍήᰴరൻߒߡ↪޿ߡ޿ࠆ㧚⊒↢ߔࠆ㛍㖸ߩ๟ᵄᢙߪ 1,578Hz ߢ޽ࠅ㧘spinning mode ߪࡕ࡯࠼(24,1)ࠍ↪޿ࠆ㧚 ⸘▚ᩰሶࠍ⸳ቯߔࠆ㓙ߦߪ߹ߕ㧘㖸Ḯ૏⟎ߣ✭ⴣ㗔ၞࠍ⠨ᘦߒߡ⸘▚㗔ၞࠍ⸳ቯߔࠆ㧚੹࿁ߩ⸃ᨆߢߪ⸘▚㗔ၞߩ y,z ᣇะߦήᰴర㐳ߐ 3 ߩ✭ⴣ㗔ၞࠍᜬߜ㧘ߘߩਛߦ⚂ 80 ὐߩᩰሶὐࠍ↪޿ࠆ㧚ߎࠇࠄߩࡄ࡜ࡔ࡯࠲ߪ㧘ㆊ෰ߩ⎇ⓥ߆ࠄචಽߥᷫ⴮ലᨐࠍᜬߞߡ޿ࠆߣ⠨߃ࠄࠇࠆ[9]㧚+x ᣇะߪߎߩ୚ߩ㗔ၞࠍᜬߞߡ޿ࠆ߇㧘-x ᣇะߪ⚂ 1.5 ߩ✭ⴣ㗔ၞࠍ⏕଻ߒߡ޿ࠆ㧚ߎࠇߪ࠽࠮࡞ࠍ
࿁᛬ߒߡᓟᣇߦ࿁ࠅㄟ߻㖸ᵄߪᒙߊ㧘චಽߦᷫ⴮ߐߖࠆߎߣ߇ߢ߈ࠆߣ⠨߃ࠄࠇࠆߚ߼ߢ޽ࠆ㧚ᰴߦ㧘㖸Ḯ๟ࠅߩ PPW ࠍ⸳ቯߒ㧘ߘࠇߦࠃߞߡ৻ߟߩ Cube ߩಽഀᢙࠍ᳿ቯߔࠆ㧚੹࿁ߩ⸃ᨆߢ
ߪ⸘▚㗔ၞߣ✭ⴣ㗔ၞࠍ᣿⏕ߦߔࠆߚ߼㧘߹ߚ㧘࠽࠮࡞๟ࠅߩᩰሶߩ⚦ಽൻࠍⴕ߁ߎߣࠍ⠨߃ᩰሶὐࠍ㈩⟎ߒߚ㧚 ࿑ 6 ߦ㧘⸘▚㗔ၞౝߩ Cube ㈩⟎ࠍ㧘⴫ 1 ߦ⸃ᨆߦ↪޿ߚᩰሶᖱႎࠍ␜ߔ㧚੹࿁ߩ⸃ᨆߢߪ Cubeᢙ߇ 708 ߣ 1,464 ߩੑߟߩ㈩⟎ߣ㧘Cube ౝߩ৻ㄝߩಽഀᢙࠍ 30 ߣ 40 ߣߒߡ㧘ว⸘ 4 ࠤ࡯ࠬߩ⸃ᨆࠍⴕ߁㧚࿑ 6(a)ߩ㈩⟎ߢߪᦨ߽ዊߐ޿ Cube ߩႺ⇇ߦ FW-H 㕙ࠍ⸳⟎ߒ㧘ߎࠇߦࠃࠅ㆙ᣇߢߩ㛍㖸ߩផቯࠍⴕ߁㧚ߚߛߒ㧘-x ᣇะߩႺ⇇ߪ࠽࠮࡞߇ㅜಾࠇࠆ૏⟎ߣߔࠆ㧚⸳⟎ߒߚ FW-H 㕙ࠃࠅ߽ᄖㇱߦ૏⟎ߔࠆ Cube ߢߪᩰሶߩ⸃௝ᐲ߇ዋߥ޿ߎߣߦࠃࠅ㛍㖸߇⥄ὼߦᷫ⴮ߔࠆ߆㧘߹ߚߪbuffer zone ๆ෼Ⴚ⇇ߦࠃߞߡᷫ⴮ߐࠇࠆ㧚࿑ 6(b)ߦ㑐ߒߡߪ࿑ 6(a)ߣหߓ૏⟎ߦ FW-H 㕙ࠍ⸳⟎ߔࠆ߇㧘ߎߩߣ߈-x ᣇะߩ FW-H 㕙ߢߪᩰሶ߇⚦ಽൻߐࠇߡ޿ࠆߚ߼㧘ߎߩಽߛߌ FW-H 㕙਄ߩᩰሶὐᢙ߇Ⴧടߒߡ޿ࠆ㧚ߐࠄߦ Case1 ߦ㑐ߒߡ㧘FW-H 㕙ߩ૏⟎ࠍᄌൻߐߖߡ㆙ᣇߢߩផቯࠍⴕ޿㧘ߎࠇࠄߩ⚿ᨐࠍ Case1-2㧘Case1-3 ߣߒߚ㧚FW-H 㕙ߩ૏⟎ߪ㧘Case1,2,3,4 ߢߪ x=[-0.5,4.0]㧘
y=[-3.0,3.0]㧘z=[-3.0,3.0]㧘Case1-2 ߪ x=[-0.5,2.5]㧘y=[-2.25,2.25]㧘z=[-2.25,2.25]㧘Case1-3 ߪ x=[-0.5,1.75]㧘
y=[-1.6,1.6]㧘z=[-1.6,1.6]ߢ޽ࠆ㧚

 !"#$%&%'()*%+,-./0123456

 (a) ੑᰴరᢿ㕙ᒻ⁁ (b) ਃᰴర STL ᒻ⁁
࿑ 5 Generic inlet ᒻ⁁(a) Case1,3(b) Case2,4
࿑ 6 ⸘▚㗔ၞౝߩ Cube ㈩⟎Min. Cell size
Caase1㩷
Ca
ase2㩷
Case3
Case4

0.0188㩷
0.0094㩷
0.02500.0125⴫ 1 ⸘▚ᩰሶߩ⹦⚦Number of
Number ofCells in one
CubeCube
40×40×40
708
40×40×40
1,464
30×30×30
708
30×30×30
1,464

Total Numberof Cells
45,312,000
93,696,000
19,116,000
39,528,000

Max. PPW
11.68
23.37
8.76
17.53

   ࿑ 7 ߦ㧘Case1㧘Case2 ߢߩ㧘z=0 ᢿ㕙ߢߩ࿶ജᄌേಽᏓࠍ␜ߔ㧚࿑ 7 ߢߪ㧘✭ⴣ㗔ၞߣߥߞߡ޿ࠆㇱಽߪ⋭޿ߡ߅ࠅ㧘߹ߚ㧘ਅඨಽߦߘࠇߙࠇߩᩰሶὐߩಽᏓࠍ৻ὐ߅߈ߦ␜ߒߡ޿ࠆ㧚࿑ 7ࠍ⷗ࠆߣ㧘ࡈࠔࡦ㕙ߢ⊒↢ߒߚ㛍㖸߇࠽࠮࡞ౝოࠍવࠊࠅ㧘ᦨ⚳⊛ߦ಴ญߢ࿁᛬ߒߡ㧘ඨᓘᣇะߦવ᠞ߒߡ޿ࠆ᭽ሶ߇⏕⹺ߢ߈ࠆ㧚߹ߚ㧘Case2 ߢߪ Case1 ߣᲧセߒߡ⸃௝ᐲ߇㜞޿ߚ߼㧘࿶ജᄌേߩࡇ࡯ࠢ߇㜞ૐ౒ߦߪߞ߈ࠅߣ⴫ࠇߡ޿ࠆ㧚࿑ 8 ߪ Case1 ߢߩ࿶ജᄌേಽᏓࠍ+x ᣇะ߆ࠄ⷗ߚ
࿑ߢ޽ࠅ㧘x ᐳᮡߏߣߦ␜ߒߡ޿ࠆ㧚⊒↢ߒߚ㛍㖸߇࿁ォߒߥ߇ࠄ৻ᣤߔ߷߼ࠄࠇ㧘ߘࠇࠍᛮߌ
ࠆߣඨᓘᣇะߦᄢ߈ߊᐢ߇ߞߡ޿ࠆ᭽ሶ߇⏕⹺ߢ߈ࠆ㧚࿑ 8 ߢߪࡈࠔࡦߪ෻ᤨ⸘࿁ࠅߦ࿁ォߒߡ޿ࠆ㧚࿶ജᄌേߩࡇ࡯ࠢߩᢙߪ㜞ૐ౒ߦ 24 ୘޽ࠅ㧘spinning mode ߩ౉ജࡕ࡯࠼ߢ޽ࠆ(24,1)ߦኻ
ᔕߒߡ޿ࠆߎߣ߇ಽ߆ࠆ㧚(a) Case1(a) x= -0.1(b) Case2࿑ᢿ㕙ߢߩ࿶ജᄌേಽᏓ
࿑ 7 z=0 ᢿ㕙ߢߩ࿶ജᄌേಽᏓ

(b) x= 0.9࿑࿑ 8 +x ᣇะ߆ࠄ⷗ߚ࿶ജᄌേಽᏓ(Case1)ᣇะ߆ࠄ⷗ߚ࿶ജᄌേಽᏓ(Case1)(c) x= 1.9

 ⴫ 2 ߦ FW-H ᴺߦ౉ജߔࠆ࿶ജᄌേߩࠨࡦࡊ࡝ࡦࠣᣇᴺࠍ␜ߔ㧚ߎߎߢ㧘Total number of cycleߪ FW-H ᴺߦ౉ജߣߒߡ↪޿ߚว⸘ߩ๟ᦼߩᢙߢ޽ࠆ߇㧘੹࿁ߩ⸃ᨆߢߪ LEE ߢߩ⸃ᨆߩ㓙ߦ 10๟ᦼಽࠍ಴ജߒ㧘ߘߩ࠺࡯࠲ࠍࠦࡇ࡯ߒߡ↪޿ߡ޿ࠆ㧚㆙ᣇߢߩ㖸࿶ᄌേࠍ᷹ቯߔࠆ૏⟎ߪ㧘࿑
5(a)ߦ⷗ࠄࠇࠆὐ(1.5,0,0)ࠍਛᔃߣߒߡඨᓘ 50 ߩ૏⟎ߦ޽ࠆὐߢ޽ࠆ㧚y=0㧘z=0 ߣߥࠆὐࠍ 0 degߣߒߡ㧘ඨᓘᣇะߦ 150 deg ߹ߢ᷹ቯߒߚ㧚



!"#$%&'&()*+&,-./01234567

 

⴫ 2 FW-H ᴺߦ౉ജߔࠆ࿶ജᄌേߩࠨࡦࡊ࡝ࡦࠣᣇᴺ
Tootal faces on
Time step per Total number ofFW--H surface
one cycle
cycle
Case1
512,000
29
Ca
ase1-2
2㩷
268,800
29
Ca
ase1-3
3㩷
139,400
29
70
Case2
684,800
58Ca
ase3㩷
288,000
21
Case4385,200
42 ࿑ 9 ߦ Case1, 2, 3 ߅ࠃ߮ 4 ߩ⸃ߩᲧセࠍ␜ߔ㧚߹ߕೋ߼ߦ㧘Case1,3 ߩᲧセࠍⴕ߁㧚40 deg ࠃࠅᄢ߈޿ⷺᐲߢߩ⸃ߦߪߘࠇ߶ߤᏅߪ⷗ࠄࠇߥ޿߇㧘0 deg ߆ࠄ 30 deg ߢߩ SPL ߪ PPW ߩૐ޿ Case3ߩᣇ߇ᄢ߈ߊߥߞߡ޿ࠆ㧚ߎࠇߪ Case3 ߩ⸃௝ᐲ߇ૐ޿ߚ߼ߦ࠽࠮࡞ḧᦛㇱߢߩ෻኿߇㗼⪺ߦ⷗ࠄࠇ㧘ㅒߦ࠽࠮࡞಴ญߦ߅ߌࠆ࿁᛬ߪ޽߹ࠅ⷗ࠄࠇߥ޿ߚ߼ߢ޽ࠆߣ⠨߃ࠄࠇࠆ㧚90 deg ࠃࠅᄢ߈޿ⷺᐲߢߩ୯ߦ߽ Case3 ߩᣇߦᝄേ߇⷗ࠄࠇ㧘વ᠞ߔࠆ㖸ᵄࠍචಽߦ⸃௝ߢ߈ߡ޿ߥ޿ߎߣ߇
ࠊ߆ࠆ㧚ACTRAN/DGM ߣߩ⸃ᨆ⚿ᨐߣᲧセߔࠆߣ㧘40 deg ߆ࠄ 120 deg ߹ߢߩ୯ߪ Case1,3 ౒ߦ߶߷৻⥌ߒߡ޿ࠆ㧚0 deg ߆ࠄ 30 deg ߩ୯ߪ Case1 ߩ⚿ᨐߦㄭ޿୯ࠍ␜ߒߡ޿ࠆ㧚߹ߚ㧘120 degએ਄ߩ୯ߪ Case1,3 ࠃࠅ߽㜞޿୯ࠍ␜ߒߡ޿ࠆ㧚ߎߩ⚿ᨐࠍ⷗ࠆߣ㧘SPL ߇ᦨᄢߣߥࠆ 40 deg ߆ࠄ 70 deg ߹ߢߩᜰะᕈߪᧄ⸘▚ᚻᴺߢ㜞޿♖ᐲߢផቯߢ߈ࠆߎߣ߇ಽ߆ߞߚ㧚ߚߛߒ㧘SPL ߇ዊߐ޿ 0 deg ߆ࠄ 30 deg ૏⟎㧘120 deg એ਄ߩ૏⟎ߢߪ㧘ࠃࠅ㜞⸃௝ᐲߩᩰሶߢߩ⸃ᨆ߇ᔅⷐߦߥࠆ
ߣ⠨߃ࠄࠇࠆ㧚ᰴߦ㧘Case1,2,3,4 ో૕ߩᲧセࠍⴕ߁㧚Case1,3 ߪၮḰߣߥࠆ PPW ߇⚂ 12 ߩᩰሶ㧘Case3,4 ߪ⚂ 9ߩᩰሶߢ޽ࠆ㧚PPW ߇ዊߐ޿ Case3 ߩᩰሶࠍ⚦ಽൻߒߚ Case4 ߢߪ㧘0 deg ߆ࠄ 30 deg ૏⟎ߢߩ
SPL ߇ࠊߕ߆ߦዊߐߊߥߞߚ㧚ߎࠇߪ࠽࠮࡞๟ࠅߩߺᩰሶߩ⚦ಽൻߦࠃߞߡ⸃௝ᐲ߇਄߇ߞߚߚ߼ߢ޽ࠆ㧚ߚߛߒ㧘⸃ో૕ߦ⷗ࠄࠇࠆᝄേߪ⚦ಽൻߦࠃߞߡ߽ᡷༀ߇⷗ࠄࠇߥ߆ߞߚ㧚ߎࠇߪ㧘
FW-H 㕙ߦ߅ߌࠆ PPW ߪ Case3 ߣ Case4 ߢᄌࠊࠄߥ޿ߚ߼ߢ޽ࠆ㧚Case1,2 ࠍᲧセߔࠆߣ㧘40 degࠃࠅᄢ߈޿ⷺᐲߩ SPL ߪ ACTRAN/DGM ߢߩ⸃ᨆ⚿ᨐߣࠃ޿৻⥌ࠍ␜ߒߡ޿ࠆ߇㧘0 deg ߆ࠄ 30deg ߩ SPL ߪᩰሶ⚦ಽൻߦࠃࠆᡷༀߪ⷗ࠄࠇߥ߆ߞߚ㧚 ࿑ 10 ߦ Case1 ߣ Case1-2,1-3 ߩ⚿ᨐࠍᲧセߔࠆ㧚ߔߴߡߩ⚿ᨐߢᄢ߈ߥᏅߪ⷗ࠄࠇߥ޿߇㧘 120deg ࠃࠅᄢ߈޿ⷺᐲ૏⟎ߢߪ Case1 ߣᲧセߒߡ㧘Case1-2,1-3 ߢߩ⸃ᨆߪࠃࠅ ACTRAN/DGM ߢߩ⸃ᨆ⚿ᨐߦㄭ޿୯ࠍ␜ߒߡ޿ࠆ㧚ߎߩℂ↱ߣߒߡ㧘Case1-2,1-3 ߢߩ⸃ᨆߢߪ FW-H 㕙⥄૕߇ዊߐߊߥࠆߚ߼ߦ㧘㆙ᣇ㖸႐ࠍផቯߔࠆ㓙ߩ᦭ല࠺࡯࠲₸߇㜞ߊߥࠆߚ߼ߢ޽ࠆ㧚ታ㓙ߦ㧘ࠃࠅᄙߊߩ FW-H 㕙࠺࡯࠲ࠍ↪޿ߡ⸃ᨆࠍⴕߞߚ⚿ᨐߢߪ㆙ᣇߢߩ⸃ᨆ⚿ᨐߪ Case1-3 ߩ⚿ᨐߦ෼᧤ߒߚ㧚 

SPL[dB]

130
120
1101009080706050ACTRAN/DGMCase1Case2
Case3
Case4

0306090Angle[deg.]

120150࿑ 9 Case1,2,3 ߅ࠃ߮ 4 ߦ߅ߌࠆ㆙ᣇ႐ SPL ߩᲧセ

SPL[dB]

130120110
1009080706050

ACTRAN/DGM
Case1
Case1-2
Case1-3
0306090Angle[deg.]

120150࿑ 10 Case1,1-2 ߅ࠃ߮ 1-3 ߦ߅ߌࠆ㆙ᣇ႐ SPL ߩᲧセ㧠㧚 ⚿⺰
 Building-Cube Method ߩࠕ࡞ࠧ࡝࠭ࡓߦၮߠߊ✢ᒻࠝࠗ࡜࡯ᣇ⒟ᑼࠦ࡯࠼ࠍ↪޿ߡ㧘⥶ⓨᯏࠛࡦࠫࡦࠍᮨߒߚゲኻ⒓࠽࠮࡞ᒻ⁁߆ࠄߩ㛍㖸વ᠞⸃ᨆࠍⴕ޿㧘⸘▚ᩰሶ߅ࠃ߮㆙ᣇ႐ផቯߦ߅ߌࠆ
౉ജ࠺࡯࠲ࠍᄌ߃ߚߣ߈ߩ㆙ᣇ႐ SPL ߩᲧセ㧘߅ࠃ߮㧘㕖᭴ㅧᩰሶᴺߦࠃࠆ⚿ᨐߣߩᲧセࠍⴕߞߚ㧚ߘߩ⚿ᨐࠍએਅߦ␜ߔ㧚 㕖᭴ㅧᩰሶᴺߢߩ⸃ᨆߣᲧセߔࠆߣ㧘ߔߴߡߩࠤ࡯ࠬߦ߅޿ߡ 0 deg ߆ࠄ 30 deg ߹ߢߩ SPL
߇ 20dB ߶ߤᄢ߈ߊߥߞߡ޿ࠆ㧚ߎࠇߪઁߩㇱಽࠃࠅ߽Ꮕ߇㗼⪺ߢ޽ࠆ㧚࠽࠮࡞๟ࠅߩ Cube ࠍ⚦ಽൻߒߚ႐วߦߪߎߩ▸࿐ߢ SPL ߪᷫዋߩ௑ะࠍ␜ߒߚߚ߼㧘㕖᭴ㅧᩰሶᴺߦ⷗ࠄࠇࠆࠃ߁ߦ㧘ߎߩઃㄭߦ߅ߌࠆ SPL ߪᧄ᧪㧘ࠃࠅዊߐߥ୯ࠍ␜ߔߣ⠨߃ࠄࠇࠆ㧚ߚߛߒ㧘0 deg ߆ࠄ 30 deg ߢߩ SPL ߪઁߩ૏⟎ߢߩ୯ߣᲧセߒߡዊߐ޿ߚ߼㧘ࠛࡦࠫࡦ߆ࠄ⊒↢ߔࠆ㛍㖸ࠍ⹏ଔߔࠆ㓙ߦߪߘࠇ߶ߤᄢ߈޿ᓇ㗀ߪߥ޿ߣ⠨߃ࠄࠇࠆ㧚 FW-H 㕙ߩ૏⟎ࠍ࠽࠮࡞ߦㄭߠߌߚ႐วߦߪ㧘120 deg એ਄ߩ૏⟎ߢߩ SPL ߦᄌൻ߇⷗ࠄࠇ㧘㕖᭴ㅧᩰሶᴺߦࠃࠆ⚿ᨐߦㄭઃ޿ߚ㧚FW-H 㕙ߩ▸࿐߇ዊߐߊߥࠆߣ㧘ߘߩಽ࠺࡯࠲㊂߇ዊߐߊߥࠆߚ߼㧘Case1-3 ߩ FW-H 㕙ߩ㈩⟎ߢ߽චಽߢ޽ࠆߣ޿߁ߎߣߪ᦭↪ߥ⚿ᨐߢ޽ࠆߣ⠨߃ࠄࠇࠆ㧚!"#$%&'&()*+&,-./01234567

 ⻢ㄉᧄ⎇ⓥߪ᧲ർᄢቇࠨࠗࡃ࡯ࠨࠗࠛࡦࠬ࠮ࡦ࠲࡯ߩࠬ࡯ࡄ࡯ࠦࡦࡇࡘ࡯࠲ࠍ೑↪ߒߡⴕߞߚ㧚⎇ⓥߦ޽ߚߞߡߪห࠮ࡦ࠲࡯㑐ଥฦ૏ߦߏᜰዉߣߏදജࠍ޿ߚߛ޿ߚ㧚߹ߚ㧘LEE ࠦ࡯࠼ߩࡌࠢ࠻࡞ൻߦߪ㧘NEC ࠪࠬ࠹ࡓ࠹ࠢࡁࡠࠫ࡯ ᦥᚒ 㓉 ᭽㧘ጊญ ஜᄥ ᭽ߩߏදജߣഥ⸒ࠍ޿ߚߛ޿ߚ㧚ᧄ⎇ⓥߪ⑼⎇⾌(21226018)ߩ੤ઃࠍฃߌߚ߽ߩߢ޽ࠆ㧚ᧄ⎇ⓥߢ↪޿ߚ Generic Inlet ᒻ⁁ߩ࠺࡯࠲㧘㕖᭴ㅧᩰሶᴺߦࠃࠆ⸘▚࠺࡯࠲ߪ Fluid Dynamics and Acoustic Group, Institute of Sound andVibration Research, University of Southampton ߆ࠄឭଏߐࠇߚ㧚⸥ߒߡ⻢ᗧࠍ⴫ߔ㧚ෳ⠨ᢥ₂[1] ᕲ↰ඳࠄ, “Building-Cube ᴺࠍ↪޿ߚ JAXA ਥ⣉ࡕ࠺࡞ߩ⹦⚦ㇱຠߩᵹ૕⸃ᨆ,” ╙ 24 ࿁ᢙ୯ᵹ૕ജቇࠪࡦࡐࠫ࠙ࡓ⻠Ṷ⺰ᢥ㓸(USB), ᮮᵿ, 2010 ᐕ 12 ᦬.
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