Shaved ob txhais ceg pom tseeb plam saum huab cua zoo dua cov plaub hau. Los yog lawv?
Puas chais koj ob txhais ceg txhim kho koj qhov kev ua tau zoo ntawm lub tsheb kauj vab? Thaum xub thawj, cov lus teb zoo li pom tseeb. Tom qab tag nrho, saib ib daim duab ntawm Sir Chris Hoy. Nws zoo kawg nkaus, brawny ob txhais ceg - cov uas yeej nws tsib kub puav pheej - yog shaved. Sib cav dhau. Tom qab tag nrho, pab pawg GB Olympic muaj koob npe vim tau hloov kev tshawb fawb ntawm marginal nce mus rau cov hlau muaj nuj nqis.
Qhov tsuas yog snag yog, Sir Chris tej zaum yuav tsis tau chais nws ob txhais ceg rau aero effect. Riders muab ntau yam laj thawj rau kev tshem tawm cov plaub hau - txiav yooj yim dua kom huv, nws chafes tsawg dua.
Ib yam tseem ceeb, shaved ob txhais ceg tsuas yog ua rau koj saib thiab xav sai. Lawv yeej cim koj tawm raws li ib tug cyclist. Los yog tsawg kawg lawv tau ua. Tam sim no muaj ib txoj kev xav hais tias cov plaub hau plaub hau tej zaum yuav tsim tsawg dua li cov du, txawm li cas los xij lawv yuav zoo li lub caij ntuj sov hnub hauv lub eeb.
Ua kom nrawm
Qhov no suab txawv. Nyob rau hauv qhov xwm txheej, ceev ceev creatures yuav luag ib txwm sleek. Ib tug yellowfin tuna (45mph) yog ib qho zoo nkauj zoo nkauj qis-dag qauv, nrog cov tawv nqaij smoother dua lub dav hlau thiab tawv, ntse fins uas quav rov qab rau hauv cov qhov rau kev kub ceev sprints.
Dolphins (txog 33mph) qhia qhov zoo sib xws rau kev nthuav dav. Dr Lissa Batey, tus kws kho tsiaj hauv hiav txwv nrog The Wildlife Trusts hais tias 'Lawv lub cev tau npog hauv cov tawv nqaij tshwj xeeb,' hais tias Dr Lissa Batey
'Lub blubber txheej ua kom cov tawv nqaij ua kom zoo. Cov txheej txheej sab nrauv kuj tseem txhim kho hydrodynamics los ntawm txuas ntxiv exuding cov roj tee thiab tso cov hlwb epithelial.
'Kev tshem tawm ntawm cov hlwb txhim kho laminar ntws los ntawm kev cuam tshuam ntawm kev tsim cov vortices thiab cov roj pab ua kom cov tawv nqaij, ua kom cov dej hla nws yooj yim dua.'
Tab sis cov neeg caij tsheb kauj vab tsis yog ntses taub ntswg ntev, thiab raws li cov tsiaj txhu hauv av peb yuav tsum mus caum tus luag qis sib txawv.
Mike Burrows, tus kws tshaj lij aerodynamics uas tsim Chris Boardman's Lotus 108 carbon TT tsheb kauj vab, piav qhia vim li cas: 'Yog tias ib yam dab tsi zoo nkauj heev, ces koj xav kom lub ntsej muag du li sai tau kom ua tiav laminar ntws.
'Yog tias ib yam dab tsi tsis zoo nkauj heev - piv txwv li koj txhais ceg - koj tsis xav tau qhov chaw du.'
Ib lus qhia ntxhib
Burrows hais txog qhov kev sim cua-qhov nto moo hauv xyoo 1930s uas tau saib ntawm qhov sawv los ntawm sab nraub qaum ntawm ib qho yooj yim.
'Nws yog ob npaug ntawm qhov loj ntawm tus kheej. Tab sis tom qab ntawd lawv muab ib daim nyias nyias nyob ib ncig ntawm tus kheej ua ntej qhov dav tshaj plaws. Nws tau txiav ib nrab ntawm txoj kab uas hla ntawm qhov sawv.'
Yog li cov plaub hau tuaj yeem nyob ntawd vim li no, zoo li kev hloov pauv hloov pauv qis qis? Puas muaj, qhov tseeb, muaj lwm yam piv txwv ntawm ceev ceev, plaub yam khoom? Zoo, yeej muaj pob ntaus pob tesniv.
'Cov plaub hau ntawm lub pob ntaus pob tuaj yeem muab nws nqa,' hais tias Derek Price, tus thawj coj ntawm Nqe Ntawm Da Dej, Tebchaws Europe tsuas yog cov chaw tsim khoom pob.
'Nws nyob ntawm seb tus neeg ntaus pob tesniv ntse npaum li cas - txawm tias nws yog sab saum toj, hauv qab kiv lossis sab kiv. Tab sis rau lub pob tsuas yog raug rho tawm haujlwm ncaj nraim, sab laug rau nws tus kheej cov cuab yeej, cov plaub hau 'cov nyhuv yog ua kom nws qeeb me ntsis.'
Tam sim no, tsis paub meej. Tej zaum Rob Dean tuaj yeem pab tau. Tsis yog nws tsuas yog Santa Cruz-sponsored endurance MTB racer, nws kuj yog ib tug kws kho tshuab ntawm General Electric (GE).
‘Kuv chais kuv ob txhais ceg kom huv si huv dua lwm yam. Kuj tseem muaj teeb meem kev nplij siab; Cov av nkos qhuav tuaj yeem ua tau zoo li lub pob bearing waggling nyob ib ncig ntawm txhua ceg plaub hau - tsis xis nyob thiab cuam tshuam.'
Aero nce?
OK, tab sis ua li cas txog aero txoj kev xav? 'Raws li tus kws tshaj lij kuv tsis ntseeg txog cov txiaj ntsig aero ntawm shaved ob txhais ceg.
'Thaum nws pab txiav cov huab cua nyob rau pem hauv ntej, cov plaub hau kuj tseem yuav txhawb nqa cov txheej txheem ciam teb tom qab, uas pab cov huab cua lo rau saum npoo thiab txo qis.
'Qhov zoo tshaj plaws yog ib tus yuav chais plaub sab pem hauv ntej thiab tawm hauv qab plaub hau. Qhov kev siv lub ntsej muag ntxhib no yog tsim los ntawm UCI hauv lub sijhawm sim sib tw.
Tab sis cov no yog cov kev daws teeb meem loj. Kuv tsis tuaj yeem xav txog leej twg sib nrug ntawm cov sijhawm sim siv qhov no. Kuv twb xav txog nws, txawm li cas los xij!'
Citing the wind-tunnel test with the sphere and wire, Burrows siv ib nrab shaving txoj kev xav ib theem ntxiv. 'Txhua yam koj xav tau yog me ntsis turbulator strip. Yog li qhov tso dag yog koj muab koj tus kheej ob npaug Mohican ntawm koj ob txhais ceg ua ntej qhov dav tshaj plaws.
'Nws nyuaj heev ua, thiab nws yuav zoo li ruam heev. Tab sis kuv xav tias British Cycling tau ua qhov no nrog lawv cov tawv nqaij. Muaj tseeb tiag rau Beijing lawv tau tham txog nws - me me turbulator strips sewn rau hauv suits mus ncig huab cua ua ntej nws tau ntws ncig koj ob txhais caj npab thiab xub pwg.
'Nws muaj peev xwm muaj txiaj ntsig zoo, txawm tias koj yuav tsum ua cua-tunnelling kom ua kom nws zoo dua.'
Lub cev ntawm pov thawj
Ib tug txiv neej uas nkag mus rau lub qhov cua yog Simon Smart, tus thawj coj ntawm Smart Aero Technology. Ib tug qub F1 engineer, Smart yog UK tus thawj coj hauv aero thev naus laus zis thiab caij txoj hauj lwm optimisation. Yog li nws paub seb cov plaub hau plaub hau - lossis qhov tsis muaj tib yam - tseem ceeb. Thiab nws tsis yog.
'Koj lub cev tuaj yeem pab txhawb ntau li 85% rau kev rub ntawm cov neeg caij tsheb / tsheb kauj vab, yog li tau txais lub cev zoo, tsis muaj kev cuam tshuam lub zog thiab kev nplij siab, yog qhov tseem ceeb tshaj plaws, 'nws hais.
'Hmoov tsis muaj cov cai nyuaj thiab nrawm - huab cua ntws ua haujlwm sib txawv nrog lub cev sib txawv thiab txoj haujlwm.'
Smart's wind-tunnel tests qhia tau hais tias qhov kho tau zoo ntawm aero tuav yog qhov tseem ceeb tshaj li lub raj ntawm Veet. Tom qab ntawd nws yog lub kaus mom hlau (qhov kev xaiv zoo tshaj plaws sib txawv ntawm tus neeg caij tsheb mus rau tus neeg caij tsheb) thiab daim tawv nqaij.
'Qhov txawv ntawm qhov zoo thiab cov tawv nqaij tsis zoo tuaj yeem muaj li 25 watts. Qhov ntawd sib npaug rau 2.5 vib nas this dhau 1km, uas yog qhov tseem ceeb hauv 25-mais lub sijhawm sim.'
Ua koj tus kheej
Tsis muaj leej twg tseem tsis tau muaj cua-qhov-kuaj ob lub Mohican sawb lossis ib nrab-shaved ceg, tab sis Burrows qhia txog qhov sib txawv uas peb txhua tus tuaj yeem sim: 'Ib 3 hli strip ntawm insulating daim kab xev rau ob sab ntawm lub raj, txog ib feem peb ntawm ib nti nyob rau hauv pem hauv ntej ntawm qhov widest. Koj yuav tsis tau ob feeb tawm ntawm nws - tab sis nws tsis raug nqi dab tsi thiab koj yuav ua tau zoo.
'Tab sis shaving los tsis? Nws yog theoretical heev. Hauv lub ntiaj teb tiag tiag nws yuav tsis muaj teeb meem ib txoj kev lossis lwm qhov.'
