Ultrasonic nrhiav kom tau acoustic yoj tshuab

Kev siv thev naus laus zis ultrasonic los ua qhov kev sim tsis muaj kev puas tsuaj ntawm cov khoom sab hauv, pib thaum xyoo 1920 thiab 1930s, tus kws tshawb fawb Soviet Sokolov tau ua tus thawj coj hauv kev siv tshuab ultrasonic los xyuas lub tswv yim ntawm qhov tsis xws luag hauv cov hlau, luam tawm. cov txiaj ntsig ntawm kev sim hauv xyoo 1935 siv txoj kev nkag mus, thiab tib lub sijhawm thov rau txoj cai los kuaj xyuas qhov tsis xws ntawm cov khoom. Raws li cov xwm txheej no, thawj cov cuab yeej tshuaj xyuas kev nkag mus tau raug tsim, tab sis thev naus laus zis siv ib qho kev xa tawm thiab ib qho tau txais kev sojntsuam, thiab qhov kev tso kawm ntawm qhov kev sojntsuam yuav tsum tau khaws cia rau ib leeg, yog li cov peev txheej ntawm daim ntawv thov raug txwv heev. Nrog rau txoj kev loj hlob ntawm no technology, nyob rau hauv lub 1940s, qhov tshwm sim ntawm pulse-reflective ultrasonic flaw detector, mus rau lub non-destructive xeem technology tau txhaj tshuaj tshiab tseem ceeb. Nyob rau hauv xyoo tas los no, kev ntsuas ultrasonic tsis muaj qhov kawg, los ntawm qhov pib nkag mus thiab Pulse reflection ultrasonic twj rau digital ultrasonic ntsuas, diffraction lub sij hawm sib txawv hom ultrasonic ntsuas, phased array ultrasonic ntsuas, thiab lwm yam., ultrasonic kuaj tshuab tau ua tau zoo thiab kev loj hlob, thev naus laus zis tau tsim txoj haujlwm tseem ceeb hauv kev tsim khoom lag luam, dav siv hauv kev lag luam hlau thiab hlau, tshuab tsim kev lag luam, cov cuab yeej tshwj xeeb, nkoj thiab aerospace kev lag luam, kev lag luam nuclear thiab lwm yam lag luam tseem ceeb. Peb lub tuam txhab lub tshuab ultrasonic feem ntau yog siv rau hauv kev tsim cov khoom siv hluav taws xob (hydroelectric generators, chav turbine generators, nuclear fais fab nroj tsuag), tswj zoo ntawm raw cov ntaub ntawv thiab cov khoom nyob rau hauv cov txheej txheem ntau lawm.
Ultrasonic kuaj siv ultrasonic yoj propagation yam ntxwv nyob rau hauv lub workpiece, lub emission phenomenon tshwm sim thaum lub suab nthwv dej ntsib lub interface ntawm ob xov xwm nrog txawv acoustic impedance. Lub hauv paus ntsiab lus ua haujlwm yog tias lub suab tsim los ntawm cov mem tes yoj mus rau hauv lub workpiece, ultrasonic tsis nyob rau hauv ib qho kev taw qhia thiab ceev rau pem hauv ntej propagation, thaum ntsib ntawm ob sab ntawm lub interface nrog txawv acoustic impedance, ib feem ntawm lub suab yoj xav rov qab los. tau txais los ntawm cov cuab yeej tshawb nrhiav, kev tshuaj xyuas ntawm qhov cuam tshuam ntawm acoustic yoj amplitude thiab txoj hauj lwm thiab lwm yam ntaub ntawv, thiab tom qab ntawd ntsuam xyuas lub workpiece yog qhov zoo lossis qhov tsis zoo thiab qhov muaj qhov tsis xws ntawm qhov loj, qhov chaw, thiab qhov xwm ntawm cov ntaub ntawv, feem ntau, nrhiav qhov tsis xws luag thiab lawv qhov kev ntsuam xyuas ntawm peb yam hauv qab no: (1) seb lub teeb liab acoustic thiab amplitude los ntawm qhov tsis xws luag; (2) qhov kev ncua deb ntawm qhov xwm txheej acoustic yoj thiab qhov tau txais acoustic yoj; (3) lub zog attenuation ntawm acoustic yoj los ntawm cov khoom.
Ultrasound yog ib tug neeg kho tshuab yoj, uas yog txhua yam kev co propagated nyob rau hauv nruab nrab. Qee qhov theorems thiab cov ntsiab lus ntawm geometric acoustics thiab lub cev acoustics feem ntau koom nrog hauv kev tshawb pom ultrasonic. Xws li cov pa ultrasound siv geometric acoustics nyob rau hauv txoj cai ntawm kev xav, refraction thiab waveform hloov dua siab tshiab, diffraction lub sij hawm sib txawv txoj kev thiab phased array nrhiav kom tau technology mas siv geometric acoustics nyob rau hauv txoj cai ntawm reflection, refraction thiab lub cev acoustic yoj diffraction thiab superposition. Mechanical yoj piav qhia ntawm lub cev tseem ceeb muaj lub sijhawm, zaus, wavelength thiab ceev.