Pamene Lamulo la Hooke silikwanira ...

Malinga ndi lamulo la Hooke lodziŵika m’mabuku a kusukulu, kutalika kwa thupi kuyenera kugwirizana ndendende ndi kupsinjika kumene kumagwiritsidwa ntchito. Komabe, zida zambiri zomwe zili zofunika kwambiri muukadaulo wamakono ndi moyo watsiku ndi tsiku zimangotsatira lamulo ili kapena kuchita mosiyana kwambiri. Akatswiri a sayansi ya zakuthambo ndi mainjiniya amanena kuti zinthu zoterezi zimakhala ndi rheological properties. Kuphunzira kwa zinthu izi kudzakhala nkhani ya zoyeserera zosangalatsa.

Rheology ndi kafukufuku wofufuza za zinthu zomwe khalidwe lake limaposa chiphunzitso cha kuthanuka kozikidwa pa lamulo la Hooke lomwe tatchulalo. Khalidweli limalumikizidwa ndi zochitika zambiri zosangalatsa. Izi zikuphatikizapo, makamaka: kuchedwa kwa kubwerera kwa zinthu ku chikhalidwe chake choyambirira pambuyo pa kutsika kwa magetsi, mwachitsanzo, elastic hysteresis; kuwonjezeka kwa elongation ya thupi pa kupsinjika kosalekeza, komwe kumatchedwa kutuluka; kapena kuwonjezeka kangapo pakukana kusinthika ndi kuuma kwa thupi loyambirira la pulasitiki, mpaka mawonekedwe a zinthu zomwe zimakhala ndi zida zowonongeka.

wolamulira waulesi

Mapeto amodzi a pulasitiki wolamulira 30 cm kapena kupitilira apo amakhazikika mu nsagwada za vise kuti wolamulirayo akhale ofukula (mkuyu. 1). Timakana mapeto apamwamba a wolamulira kuchokera kumtunda ndi mamilimita ochepa chabe ndikumasula. Zindikirani kuti gawo laulere la wolamulira limazungulira kangapo kuzungulira malo osakanikirana ndikubwerera ku chikhalidwe chake choyambirira (mkuyu 1a). Ma oscillations omwe amawonedwa ndi ogwirizana, popeza pakupatuka kwakung'ono kukula kwa mphamvu yotanuka yomwe imagwira ntchito ngati mphamvu yotsogolera imagwirizana mwachindunji ndi kupatuka kwa kumapeto kwa wolamulira. Khalidwe ili la wolamulira likufotokozedwa ndi chiphunzitso cha elasticity. 

Mpunga. 1. Phunziro la zotanuka hysteresis pogwiritsa ntchito wolamulira

1 - ambulansi,

2 - vise nsagwada, A - kupatuka kwa mapeto a wolamulira kuchokera ofukula

Mu gawo lachiwiri la kuyesa, timapatutsa kumapeto kwa wolamulira ndi masentimita angapo, kumasula, ndikuwona khalidwe lake (mkuyu 1b). Tsopano mapeto awa akubwerera pang'onopang'ono kumalo ogwirizana. Izi ndichifukwa chakuchulukirachulukira kwa malire otanuka a zinthu zolamulira. Izi zimatchedwa zotanuka hysteresis. Zimakhala ndi kubwerera pang'onopang'ono kwa thupi lopunduka kumalo ake oyambirira. Ngati tibwereza kuyesera kotsirizaku popendekera kumapeto kwapamwamba kwa wolamulira kwambiri, tidzapeza kuti kubwerera kwake kudzakhalanso pang'onopang'ono ndipo kungatenge mphindi zingapo. Kuphatikiza apo, wolamulirayo sadzabwereranso chimodzimodzi pamalo oyima ndipo azikhala wopindika mpaka kalekale. Zotsatira zomwe zafotokozedwa mu gawo lachiwiri la kuyesako ndi chimodzi mwa izo maphunziro a rheology.

Mbalame yobwerera kapena kangaude

Pazotsatirapo, tidzagwiritsa ntchito chidole chotsika mtengo komanso chosavuta kugula (nthawi zina chimapezeka m'makiosks). Amakhala ndi fano lathyathyathya mu mawonekedwe a mbalame kapena nyama zina, monga kangaude, olumikizidwa ndi lamba wautali ndi chogwirira mphete (mkuyu 2a). Chidole chonsecho chimapangidwa ndi zinthu zolimba, ngati mphira zomwe zimamatira pang'ono kukhudza. Tepiyo imatha kutambasulidwa mosavuta, kukulitsa kutalika kwake kangapo popanda kuing’amba. Timayesa pafupi ndi malo osalala, monga galasi lagalasi kapena khoma la mipando. Ndi zala za dzanja limodzi, gwirani chogwiriracho ndikugwedezani, potero mukuponya chidolecho pamalo osalala. Mudzawona kuti chifanizirocho chimamamatira pamwamba ndipo tepiyo imakhala yolimba. Timapitiriza kugwira chogwiriracho ndi zala zathu kwa masekondi angapo kapena kuposerapo.

Mpunga. 2. Chitsanzo chowoneka bwino cha zotanuka hysteresis, zosonyezedwa pogwiritsa ntchito mtanda wobwerera

1 - chifaniziro cha kangaude, 2 - gulu la rabala,

3 - chogwirira, 4 - kanjedza, 5 - pamwamba

Patapita kanthawi, tikuwona kuti fanolo lidzatuluka mwadzidzidzi pamwamba ndipo, kukopeka ndi tepi yochepetsera kutentha, idzabwerera mwamsanga m'manja mwathu. Pankhaniyi, monga momwe adayesera kale, palinso kuwola pang'onopang'ono kwa magetsi, mwachitsanzo, elastic hysteresis. Mphamvu zotanuka za tepi yotambasulidwa zimagonjetsa mphamvu zomata za chitsanzo pamwamba, zomwe zimafooketsa pakapita nthawi. Zotsatira zake, chiwerengerocho chimabwerera ku dzanja. Zomwe zimagwiritsidwa ntchito poyesera izi zimatchedwa rheologists viscoelastic. Dzinali ndi lolungama chifukwa limasonyeza zonse zomata - pamene zimamatirira pamtunda wosalala, ndi zotanuka - chifukwa chake zimachoka pamtunda ndikubwerera ku chikhalidwe chake choyambirira.

munthu akutsika

Chithunzi 1. Chithunzi chotsika khoma loyima ndi chitsanzo chabwino cha zotanuka hysteresis.

Kuyesaku kudzagwiritsanso ntchito chidole chopezeka mosavuta chopangidwa ndi viscoelastic material (chithunzi 1). Amapangidwa ngati chithunzi cha munthu kapena kangaude. Timaponyera chidole ichi ndi miyendo yoyikidwa ndikutembenukira pansi pamtunda wathyathyathya, makamaka pagalasi, galasi kapena khoma la mipando. Chinthu choponyedwa chimamamatira pamwamba apa. Patapita nthawi, nthawi yomwe imadalira, mwa zina, pazovuta za pamwamba ndi kuthamanga kwa kuponyera, pamwamba pa chidolecho chimachoka. Izi zimachitika chifukwa cha zomwe zidakambidwa kale. zotanuka hysteresis ndi zochita za kulemera kwa chiwerengerocho, chomwe chimalowa m'malo mwa mphamvu yotanuka ya lamba, yomwe inalipo mukuyesera koyambirira.

Potengera kulemera, gawo lodzipatula la chidolecho limawerama ndikusweka motalikirapo mpaka gawolo likhudzanso pamwamba pake. Pambuyo pa kukhudza uku, gluing lotsatira la chithunzi pamwamba limayamba. Zotsatira zake, chithunzicho chidzalumikizidwanso, koma pamutu-pansi. Njira zomwe zafotokozedwa pansipa zikubwerezedwa, ndi ziwerengerozo zimang'amba miyendo ndiyeno mutu. Zotsatira zake n’zakuti chithunzicho chimatsikira molunjika, n’kupanga zopendekera mochititsa chidwi.

Plasticine wamadzi

Mpunga. 3. Kuyesa kwa pulasitiki

a) chiyambi, b) chomaliza;

1 - kanjedza, 2 - kumtunda kwa pulasitiki,

3 - chizindikiro, 4 - constriction, 5 - chidutswa cha pulasitiki chong'ambika

Muzoyesa izi ndi zingapo zotsatila, tidzagwiritsa ntchito pulasitiki yomwe imapezeka m'masitolo ogulitsa zidole, omwe amadziwika kuti "dongo lamatsenga" kapena "tricolin". Timakanda chidutswa cha pulasitiki mu mawonekedwe ofanana ndi dumbbell, pafupifupi 4 cm yaitali ndi m'mimba mwake wa zigawo zokulirapo mkati mwa 1-2 masentimita ndi m'mimba mwake pafupifupi 5 mm (mkuyu 3a). Timagwira ndikumangirako ndi zala zathu kumapeto kwenikweni kwa gawo lokhuthala ndikuligwira mosasunthika kapena kulipachika molunjika pafupi ndi cholembera chomwe chikuwonetsa komwe kuli kumapeto kwa gawo lokhuthala.

Poyang'ana malo a kumapeto kwa pulasitiki, tikuwona kuti pang'onopang'ono ikuyenda pansi. Pankhaniyi, gawo lapakati la pulasitiki limaponderezedwa. Njirayi imatchedwa kuyenda kapena kukwawa kwa zinthuzo ndipo kumaphatikizapo kuwonjezera kutalika kwake pansi pa kupsinjika kosalekeza. Kwa ife, kupsinjika kumeneku kumayambitsidwa ndi kulemera kwa gawo lapansi la dumbbell ya plasticine (mkuyu 3b). Kuchokera pamalingaliro ang'onoang'ono panopa izi ndi zotsatira za kusintha kwa kapangidwe ka zinthu zomwe zimaperekedwa ku katundu kwa nthawi yayitali mokwanira. Panthawi ina, mphamvu ya gawo lopapatiza ndi yaying'ono kwambiri moti imasweka pansi pa kulemera kwa gawo la pansi la pulasitiki lokha. Kuthamanga kumadalira pazinthu zambiri, kuphatikizapo mtundu wa zinthu, kuchuluka kwake ndi njira yogwiritsira ntchito kupanikizika kwa izo.

Pulasitiki yomwe timagwiritsa ntchito imakhala yovuta kwambiri kuyenda, ndipo timatha kuiwona ndi maso pamasekondi ochepa chabe. Ndikoyenera kuwonjezera kuti dongo lamatsenga linapangidwa mwangozi ku United States, panthawi ya nkhondo yachiwiri ya padziko lonse, pamene kuyesa kupangidwa kupanga zinthu zopangira zopangira matayala a magalimoto ankhondo. Chifukwa cha polymerization yosakwanira, zinthu zinapezedwa momwe ma molekyulu angapo anali osamangidwa, ndipo zomangira pakati pa mamolekyu ena zimatha kusintha mosavuta malo awo mothandizidwa ndi zinthu zakunja. Maulalo "oboola" awa amathandizira kudabwitsa kwa dongo lodumphira.

mpira wopita

Mpunga. 4. Khazikitsani kuyesa pulasitiki kuti ifalitse komanso kupumula kupsinjika:

a) chiyambi, b) chomaliza; 1 - mpira wachitsulo,

2 - chotengera chowonekera, 3 - pulasitiki, 4 - maziko

Tsopano Finyani matsenga plasticine mu chotengera chaching'ono mandala, kutsegula pamwamba, kuonetsetsa kuti mulibe thovu mpweya mmenemo (mkuyu. 4a). Kutalika ndi m'mimba mwake a chotengera ayenera kukhala angapo centimita. Ikani mpira wachitsulo pafupifupi 1,5 masentimita m'mimba mwake pakati pa pamwamba pa pulasitiki, timasiya chombocho ndi mpirawo. Maola angapo aliwonse timawona momwe mpirawo ulili. Zindikirani kuti imapita mozama kwambiri mu pulasitiki, yomwe imalowa mumlengalenga pamwamba pa mpirawo.

Pambuyo pa nthawi yayitali yokwanira, zomwe zimadalira: kulemera kwa mpira, mtundu wa pulasitiki wogwiritsidwa ntchito, kukula kwa mpira ndi poto, kutentha kozungulira, timawona kuti mpirawo umafika pansi pa poto. Danga pamwamba pa mpira lidzadzazidwa kwathunthu ndi plasticine (mkuyu 4b). Kuyesera uku kukuwonetsa kuti zinthu zikuyenda komanso kuthetsa nkhawa.

Kudumpha kwa pulasitiki

Pangani mtanda wamatsenga ndikuuponya pamalo olimba monga pansi kapena khoma. Tikuwona modabwa kuti pulasitiki imadumphira pamalo awa ngati mpira wa rabara. Dongo lamatsenga ndi thupi lomwe limatha kuwonetsa pulasitiki komanso zotanuka. Zimatengera momwe katunduyo achitirapo mwachangu.

Pamene kupsyinjika kumagwiritsidwa ntchito pang'onopang'ono, monga momwe zimakhalira pokanda, zimawonetsa pulasitiki. Kumbali ina, mphamvu ikagwiritsidwa ntchito mofulumira, zomwe zimachitika pamene ziwombana ndi pansi kapena khoma, pulasitiki imasonyeza zotanuka. Dongo lamatsenga limatha kutchedwa mwachidule thupi lapulasitiki-elastic.

Plasticine wokhazikika

Chithunzi 2. Zotsatira za kutambasula pang'onopang'ono kwa dongo lamatsenga (kutalika kwa ulusi wotambasula ndi pafupifupi 60 cm)

Panthawiyi, pangani silinda yamatsenga yamatsenga pafupifupi 1 cm m'mimba mwake ndi masentimita angapo kutalika. Tengani mbali zonse ziwiri ndi zala za dzanja lanu lamanja ndi lamanzere ndikuyika chogudubuza mopingasa. Kenaka timatambasula manja athu pang'onopang'ono kumbali mu mzere umodzi wowongoka, motero timachititsa kuti silinda itambasulire mbali ya axial. Timamva kuti pulasitiki imapereka pafupifupi kukana, ndipo tikuwona kuti imachepa pakati.

Kutalika kwa silinda ya plasticine kumatha kuonjezedwa mpaka makumi angapo masentimita, mpaka ulusi wochepa thupi upangike pakatikati pake, womwe umatha pakapita nthawi (chithunzi 2). Chochitikachi chikuwonetsa kuti pogwiritsira ntchito pang'onopang'ono kupsinjika kwa thupi lapulasitiki-elastic, munthu angayambitse kusokonezeka kwakukulu popanda kuwononga.

pulasitiki wolimba

Timakonzekera silinda yamatsenga yamatsenga mofanana ndi kuyesa koyambirira ndikukulunga zala zathu kumapeto kwake mofanana. Titayang'ana chidwi chathu, timatambasula manja athu m'mbali mwachangu momwe tingathere, tikufuna kutambasula mwamphamvu silindayo. Zikuoneka kuti mu nkhani iyi timamva kwambiri kukana kwa pulasitiki, ndi yamphamvu, n'zosadabwitsa, si kutalikitsa konse, koma kusweka mu theka kutalika kwake, ngati kudula ndi mpeni (chithunzi 3). Kuyesera uku kukuwonetsanso kuti chikhalidwe cha kusinthika kwa thupi lapulasitiki-elastic zimadalira kuchuluka kwa ntchito yopanikizika.

Plasticine ndi wosalimba ngati galasi

Chithunzi 3. Chotsatira cha kutambasula mofulumira kwa pulasitiki yamatsenga - mumatha kuona nthawi zambiri kufupikitsa komanso m'mphepete lakuthwa, lofanana ndi kuphulika kwa zinthu zosalimba.

Kuyesera uku kukuwonetsa momveka bwino momwe kuchuluka kwa kupsinjika kumakhudzira thupi la pulasitiki-elastic. Pangani mpira wokhala ndi mainchesi pafupifupi 1,5 cm kuchokera ku dongo lamatsenga ndikuwuyika pamalo olimba, okulirapo, monga chitsulo cholemera kwambiri, chivundikiro, kapena pansi pa konkire. Pang'onopang'ono kugunda mpira ndi nyundo masekeli osachepera 0,5 makilogalamu (mkuyu. 5a). Zikuwonekeratu kuti panthawiyi mpirawo umakhala ngati thupi la pulasitiki ndipo umagwedezeka pambuyo nyundo itagwa pa izo (mkuyu 5b).

Pangani pulasitiki wophwanyika kukhala mpira kachiwiri ndikuyiyika pa mbale monga kale. Apanso timamenya mpira ndi nyundo, koma nthawi ino timayesetsa kuchita mwamsanga (mkuyu 5c). Zikuoneka kuti mpira wa pulasitiki mu nkhani iyi amachita ngati kuti anapangidwa ndi zinthu zosalimba, monga galasi kapena zadothi, ndipo pa zimakhudza izo shatters mu zidutswa mbali zonse (mkuyu 5d).

Makina otentha pamagulu opangira mphira

Kupanikizika mu rheological zipangizo akhoza kuchepetsedwa ndi kukweza awo kutentha. Tidzagwiritsa ntchito izi mu injini yotentha yokhala ndi mfundo yodabwitsa yogwira ntchito. Kuti musonkhanitse, mufunika: chipewa cha mtsuko wa malata, mphira khumi ndi ziwiri kapena zazifupi, singano yayikulu, chitsulo chopyapyala chamakona anayi, ndi nyali yokhala ndi babu yotentha kwambiri. Mapangidwe a galimotoyo akuwonetsedwa mu chithunzi 6. Kuti asonkhanitse, dulani gawo lapakati kuchokera pachivundikirocho kuti mphete ipezeke.

Mpunga. 5. Njira yowonetsera zinthu zapulasitiki ndi zowonongeka za plasticine

a) Kumenya mpira pang'onopang'ono b) Kumenya pang'onopang'ono

c) kugunda mwachangu pa mpira, d) zotsatira za kugunda mwachangu;

1 - mpira wa pulasitiki, 2 - mbale yolimba ndi yayikulu, 3 - nyundo,

v - liwiro la nyundo

Pakatikati mwa mphete iyi timayika singano, yomwe ndi axis, ndikuyikapo zingwe zotanuka kuti pakati pa kutalika kwake zipume motsutsana ndi mpheteyo ndipo zimatambasulidwa mwamphamvu. Zingwe zotanuka ziyenera kuyikidwa molingana pa mpheteyo, motero, gudumu lokhala ndi masipoko opangidwa kuchokera kumagulu otanuka amapezeka. Pindani chidutswa chachitsulo mu mawonekedwe a crampon ndi manja atatambasula, kukulolani kuti muyike bwalo lopangidwa kale pakati pawo ndikuphimba theka la pamwamba pake. Kumbali imodzi ya cantilever, kumbali zonse ziwiri zoyima, timapanga chodulira chomwe chimatilola kuyika gudumu m'mphepete mwake.

Ikani gudumu lachitsulo podula chothandizira. Timatembenuza gudumu ndi zala zathu ndikuyang'ana ngati ili bwino, i.e. imayima pamalo aliwonse. Ngati sizili choncho, sungani gudumu posuntha pang'ono malo omwe magulu a rabala amakumana ndi mphete. Ikani bulaketi patebulo ndikuwunikira gawo la bwalo lomwe likutuluka m'makona ake ndi nyali yotentha kwambiri. Zikuoneka kuti patapita kanthawi gudumu limayamba kuzungulira.

Chifukwa cha kayendedwe kameneka ndikusintha kosalekeza kwa malo apakati a misa ya gudumu chifukwa cha zotsatira zotchedwa rheologists. kutentha kupsinjika maganizo.

Izi zosangalatsa zachokera chakuti kwambiri anatsindika zotanuka zakuthupi mgwirizano pamene usavutike mtima. Mu injini yathu, zinthu izi ndi magudumu a rabara omwe amatuluka pa bulaketi ndikuwotchedwa ndi babu. Chotsatira chake, pakati pa misa ya gudumu imasunthidwa kumbali yophimbidwa ndi mikono yothandizira. Chifukwa cha kuzungulira kwa gudumu, magulu a mphira otentha amagwera pakati pa mapewa a chithandizo ndikuzizira pansi, popeza amabisika ku babu. Zofufutira zoziziritsidwa zimatalikitsanso. Kutsatizana kwa ndondomeko zofotokozedwa kumatsimikizira kusinthasintha kosalekeza kwa gudumu.

Osati kuyesa kochititsa chidwi kokha

Mpunga. 6. Mapangidwe a injini yotentha yopangidwa ndi magulu a mphira a mankhwala

a) mawonekedwe a mbali

b) gawo ndi axial ndege; 1 - mphete, 2 - singano, 3 - chofufutira chamankhwala,

4 - bulaketi, 5 - cutout mu bulaketi, 6 - babu

Tsopano rheology ndi gawo lomwe likukula mofulumira kwa akatswiri a sayansi ya sayansi ndi akatswiri a sayansi yaukadaulo. Zochitika za Rheological nthawi zina zimatha kukhala ndi zotsatira zoyipa pazomwe zimachitika ndipo ziyenera kuganiziridwa, mwachitsanzo, popanga zida zazikulu zachitsulo zomwe zimapunduka pakapita nthawi. Zimachokera ku kufalikira kwa zinthu pansi pa zochita zolemetsa ndi kulemera kwake.

Miyezo yolondola ya makulidwe a mapepala amkuwa ophimba madenga otsetsereka ndi mazenera agalasi opaka m'matchalitchi odziwika bwino awonetsa kuti zinthu izi ndi zokhuthala pansi kuposa pamwamba. Izi ndi zotsatira panopazonse zamkuwa ndi galasi pansi pa kulemera kwawo kwa zaka mazana angapo. Zochitika za Rheological zimagwiritsidwanso ntchito muukadaulo wambiri wamakono komanso wachuma. Chitsanzo ndi kukonza mapulasitiki. Zambiri zopangidwa kuchokera kuzinthu izi zimapangidwa ndi extrusion, kujambula ndi kuwomba. Izi zimachitika mutatha kutentha zinthuzo ndikuzikakamiza pamlingo wosankhidwa bwino. Choncho, mwa zina, zojambulazo, ndodo, mapaipi, ulusi, komanso zoseweretsa ndi ziwalo zamakina zokhala ndi mawonekedwe ovuta. Ubwino wofunikira kwambiri wa njirazi ndizotsika mtengo komanso zosawononga.