Qhov sib txawv tseem ceeb ntawm convection thiab diffusion yog tias convection yog qhov loj ntawm qhov loj ntawm cov khoom nyob rau hauv tib txoj kev los ntawm cov kua, whereas diffusion yog lub zog ntawm ib tug hais thiab hloov ntawm particle lub zog thiab lub zog mus rau lwm yam. cov khoom hauv cov kua.
Convection thiab diffusion yog ob lub cev txheej txheem peb tuaj yeem piav qhia txog tshuaj lom neeg los ntawm kev txav ntawm cov khoom.
Convection yog dab tsi?
Convection yog cov txheej txheem ntawm kev hloov hluav taws xob los ntawm kev txav ntawm cov molecules hauv cov kua. Cov kua yuav ua tau roj los yog kua. Thaum xub thawj, cov cua kub hloov ntawm cov kua thiab ib yam khoom tshwm sim los ntawm conduction; Txawm li cas los xij, qhov hloov pauv kub ntau tshwm sim vim qhov kev txav ntawm cov kua dej. Peb tuaj yeem hais tias convection yog cov txheej txheem hloov hluav taws xob hauv cov kua los ntawm qhov tseeb ntawm qhov teeb meem. Cov txheej txheem no tuaj yeem tshwm sim raws li lub ntuj tsim lossis raug yuam.
Txog cov txheej txheem ntawm convection, cua sov cov kua ua rau thermal expansion, thiab cov khaubncaws sab nraud povtseg uas nyob ze rau qhov cua sov qhov chaw tau kub thiab ua tsis tshua muaj ntom. Yog li, ua raws li qhov no yog qhov nce ntawm qhov kub ntawm cov kua dej raws li kev sib tw uas cov txheej txheem dej txias yuav hloov cov txheej txheem dej kub nce. Cov txheej txheem no rov ua dua, thiab nws yog txheej txheem ntawm convection qhov twg cov cua sov hloov mus.
Muaj ob hom convection li natural convection thiab yuam convection. Ntuj convection tshwm sim vim lub zog buoyant, thiab yuam convection tshwm sim vim yog ib qho chaw sab nraud xws li cua los ntawm kiv cua lossis lub twj tso kua mis.
Diffusion yog dab tsi?
Diffusion yog qhov txav ntawm cov molecules los ntawm thaj tsam ntawm qhov siab mus rau qhov tsis tshua muaj siab ntawm qhov concentration gradient. Cov kev txav no tshwm sim hauv tib txoj kev daws teeb meem. Cov yam ntxwv uas cuam tshuam rau qhov concentration gradient cuam tshuam rau kev nthuav dav thiab.
Nyob rau hauv kev nthuav dav, cov lus tsa suab no raug txiav tawm thaum qhov sib npaug ntawm ob cheeb tsam sib npaug ntawm txhua qhov chaw. Qhov no txhais tau tias qhov kev txav no tshwm sim kom txog thaum lub concentration gradient ploj mus. Tom qab ntawd cov molecules kis mus rau txhua qhov chaw hauv cov tshuaj.
Tus nqi ntawm kev txav ntawm cov molecules los ntawm kev sib kis yog qhov ua haujlwm ntawm qhov kub thiab txias, qhov viscosity ntawm cov roj (los yog kua) thiab qhov loj me. Feem ntau, molecular diffusion piav qhia txog cov net flux ntawm molecules los ntawm ib cheeb tsam ntawm siab concentration mus rau ib tug tsawg concentration. Thaum xav txog ob lub tshuab, A1 thiab A2, uas nyob rau tib qhov kub thiab muaj peev xwm sib pauv cov molecules ntawm lawv, kev hloov pauv ntawm lub zog muaj peev xwm ntawm ob lub tshuab no tuaj yeem tsim lub zog ntws los ntawm ib qho mus rau lwm qhov (los ntawm A1. rau A2 los yog vice versa). Qhov no yog vim txhua qhov system ib txwm nyiam qis zog thiab siab entropy xeev. Qhov no tsim ib lub xeev ntawm molecular diffusion.
Qhov txawv ntawm Convection thiab Diffusion yog dab tsi?
Convection thiab diffusion yog cov txheej txheem ntawm lub cev peb tuaj yeem piav qhia txog tshuaj lom neeg los ntawm kev txav ntawm cov khoom. Qhov sib txawv tseem ceeb ntawm convection thiab diffusion yog tias convection yog qhov loj ntawm qhov loj ntawm cov khoom nyob rau hauv tib txoj kev los ntawm cov kua, whereas diffusion yog lub zog ntawm ib tug hais thiab hloov particle lub zog thiab lub zog mus rau lwm yam hais nyob rau hauv cov kua.
Cov infographic hauv qab no teev qhov sib txawv ntawm convection thiab diffusion hauv daim ntawv tabular rau ib sab ntawm kev sib piv.
Summary – Convection vs Diffusion
Convection yog cov txheej txheem ntawm kev hloov hluav taws xob los ntawm kev txav ntawm cov molecules hauv cov kua. Diffusion yog qhov txav ntawm cov molecules los ntawm thaj tsam ntawm qhov siab mus rau qhov tsis tshua muaj siab ntawm qhov concentration gradient. Yog li ntawd, qhov sib txawv tseem ceeb ntawm convection thiab diffusion yog tias convection yog qhov loj ntawm qhov loj ntawm cov khoom nyob rau hauv tib txoj kev los ntawm cov kua, whereas diffusion yog lub zog ntawm ib tug hais thiab hloov ntawm particle lub zog thiab lub zog mus rau lwm yam hais nyob rau hauv lub diffusion. dej.
