Coefficient na zamiya gogayya da kuma mirgina

A nazarin sasannin yanayi wani motsi jiki (ko zuwa a tashin) a lamba tare da kewaye yanayi ko abu tare da wasu gawawwaki. A wannan yanayin, dakarun bayyana cewa samar da juriya ga su motsi. Wadannan dakarun kira gogayya sojojin da suka canja wurin wani ɓangare na da inji makamashi na motsi a cikin ciki makamashi, wanda yana tare da dumama jikinsu da kuma muhalli.

Gogayya ne waje da ciki. Ciki (in ba haka ba ya kira danko) ne da ya faru na tangential sojojin tsakanin motsi ruwa ko gas Layer da cewa ya hana wannan yunkuri.

A bambanci, external gogayya auku a lamba na daskararru, a cikin hanyar karfi tangential ga surface kuma impeding juna motsi. Yana, bi da bi, ne zuwa kashi a tsaye (a tsaye gogayya) da kuma kinematic. A tsaye gogayya bayyana lokacin da ka yi kokarin motsa jiki daya zumunta zuwa wani tsit. Kinematic wanzu tsakanin motsi jikinsu, a lamba tare da juna. External gogayya za a iya raba mirgina da zamiya gogayya.

Mene ne ma'anar jiki na gogayya? Yana da amfani ko cutarwa? A duban farko, gogayya kawai ya hana mu ci inji sassa, mota tayoyin, takalma soles ake sharewa, da dai sauransu da kuma kafa .. Perpetual motsi kawai ba zai yiwu ga wannan dalilin. Amma duba a hankali a hankali. Gogayya bace - ba za mu iya ba tafiya kuma flipping littafin ko ja tafi da mota, ko a daina motsi. A babbar yawan jiki mamaki a duniya dogara ne a kan gogayya. The biyu main nasarori daga mutãne da suka dimbin yawa da ci gaban wayewar - samar da wuta da kuma sabuwar dabara na da dabaran - ba zai yiwu ba ba tare da shi.

Wannan sabon abu ne dangane da magudi da wani jikinsu: daya daraja a lamba ko da yaushe jingina zuwa ga surface roughness na sauran. Domin a daidai santsi (msl, a hankali goge) saman tam dab da juna, da dokokin kwayoyin gogayya dogara ne a kan juna janye daga cikin kwayoyin.

Karantar kimiyya gogayya tribology. A 1781, Faransa likita C. Coulomb tsara ka'idojin bushe gogayya. Empirically, da masu bincike gano cewa, da gogayya da karfi ne F, abin da ke faruwa a lokacin da zamiya, shi ne kai tsaye na gwargwado ga karfi aiki a kan wani jiki N al'ada matsa lamba. Wannan dangantaka ne kamar haka:

N: F = k ∙ N;

inda da yawa k - gogayya coefficient (gwargwado coefficient). Its darajar da aka lasafta kamar haka: A jikin da aka sanya a kan karkata jirgin sama da kuma ta karkatar da shi kai wani uniform motsi. A wannan yanayin, da gogayya da karfi F ne daidai da tuki da karfi na P:

F = P ∙ zunubi a.

A karfi N (al'ada matsa lamba karfi) ne daidai P ∙ cos wani. saboda haka k = KU wani. A coefficient na gogayya ne a nan cikin tangent na surface karkata kwana a da nunin jiki gaba ɗaya, watau. E. A akai gudun.

A aikace, da darajar za a iya lasafta kawai kamar. A surface na jiki, yawanci a daya mataki ko wani gurbata ne oxides, tsatsa da sauran impurities. gogayya coefficient ƙaddara pairwise haduwa da daban-daban kayan da gwaje-gwajen, da aka gabatar a cikin na musamman reference Tables.

Mirgina gogayya mai tushe daga gaskiya cewa wani dabba ba a kanta dabaran ne dan kadan guga man a cikin hanya surface, watau. E. Yana yana shawo wata kananan hillock. The wuya hanya, da kasa da karo da kasa gogayya da karfi. Da darajar da aka lasafta a cikin wannan hali ta hanyar da dabara: F = k ∙ N / r, a cikin abin da r - darajar da dabaran radius. Saboda haka, da mirgina gogayya coefficient yana da tsawon girma. Yawancin lokaci shi ne aka bayyana a cikin santimita a matsayin adawa da zamiya gogayya coefficient, wanda shi ne mai dimensionless yawa.

Kamar yadda aka ambata a sama, da ciki gogayya coefficient wanzu ba kawai don daskararru amma kuma zuwa taya. A hydraulics ne sau da yawa ake bukata yin lissafi da takamaiman makamashi hasara a na'ura mai aiki da karfin ruwa da tsarin tasowa a cikin bututun. Su na iri biyu: asara a tsawon asali mike bututu tare da uniform da kwarara, da kuma gida asara saboda - kwarara nakasawa saboda canje-canje a tashar siffar (ƙanƙancewa, fadada, juyawa). Na'ura mai aiki da karfin ruwa asarar da aka lasafta ta yin amfani da wannan darajar, wanda ake kira da "coefficient na na'ura mai aiki da karfin ruwa gogayya".