Ngā Huarahi Māmā ki te Mārama ki ngā Tikanga o te Mīhini Tīhiera
Ko te mīhini tīhiera he momo mīhini tahunga ā-roto e whakamahia whānuitia ana i roto i ngā waka me ngā taputapu ahumahi. E mōhiotia ana mō tōna pai me tōna roa, ko ngā mīhini tīhiera te mea matua mō ngā tono e hiahia ana ki te mahi nui me te roa. Heoi, ki te tokomaha, he uaua te mārama ki ngā tikanga o te mīhini tīhiera. Nō reira, mā tēnei tuhinga ka whakaratohia he whakamārama ngāwari ki te mārama mō te mahi a te mīhini tīhiera me ōna wāhanga.
1. Te Mahi a te Mīhini Tīhiera
Ko ngā miihini tahunga ā-roto katoa, tae atu ki ngā miihini tīhiera, ka mahi i runga i tētahi huringa thermodynamic motuhake. Ka mahi ngā miihini tīhiera i runga i te huringa tīhiera, he rerekē tēnei i te huringa Otto e whakamahia ana e ngā miihini penehīni. E whā ngā wāhanga matua o te huringa tīhiera: te whakauru, te kōpeketanga, te tahunga, me te whakaputanga hau.
– Te Whakaurunga: I tēnei wāhanga, ka tomo te hau parakore ki roto i te rango mā te takirere whakauru i te nekehanga o te piston ki raro. Kāore i rite ki te miihini penehīni, kāore he ranunga wahie-hau i tēnei wāhanga.
– Te Kōpeketanga: I te nekenga ake o te piston, ka kōpeketia te hau i roto i te rango ki ngā pēhanga me ngā pāmahana tino teitei. I roto i ngā miihini tīhiera, he nui ake te ōwehenga kōpeketanga i ngā miihini penehīni, i waenganui i te 14:1 me te 25:1.
– Te tahunga: Ina eke te piston ki tōna taumata teitei i te wā o te pēhanga, ka werohia te wahie tīhiera ki roto i te rango mā te werohanga. Kātahi ka taunekeneke tēnei wahie ki te hau, kua tino wera nā te pēhanga teitei, ā, ka puta noa te tahunga. Kāore he mura horihori pērā i te puru mura i roto i te miihini penehīni.
– Putanga hau: Ka panaia te piston ki raro e ngā hau mura e puta ana, ka whakaputa i te mana e pana ana i te porowhita. Kātahi ka panaia ngā hau putanga hau i roto i te rango mā roto i te takirere putanga hau i te mea ka neke ake anō te piston.
2. Ngā Wāhanga Matua o te Mīhini Tīhiera
Hei mārama katoa ki ngā mahi a te miihini tīhiera, he mea nui te mārama ki ōna wāhanga matua. Anei ētahi wāhanga matua o te miihini tīhiera me ā rātou mahi:
– Poraka Pūoto: Ko te wāhanga matua o te mīhini e pupuri ana i te pūoto, te piston, me ngā momo hongere wai whakamatao me te hinu whakahinuhinu.
– Pistona: Ko te wāhanga e neke ake ana, e heke iho ana hoki i roto i te rango, ā, koia te kawenga mō te huri i te pūngao mai i te tahunga ki te nekehanga miihini.
– Poro Porowhita (Poro Porowhita): He poro e huri ai te nekehanga raina o te piston hei nekehanga hurihuri e akiaki ana i ngā wira o tētahi waka, taputapu rānei.
– Camshaft (Camshaft): He kawenga mō te whakahaere i te whakatuwheratanga me te katinga o ngā takirere whakauru me te takirere whakaputa, mā te nekehanga hurihuri ka hurihia hei nekehanga raina e ngā ringa ruku (ngā ringa taraiwa).
– Werohanga: He wāhanga e werohanga ana i te wahie tīhiera ki roto i te rango i te pēhanga teitei, ka puta he rehu pai, he mura.
– Pūkaha turbo: He maha ngā miihini tīhiera hou he pūkaha turbo, e whakamahi ana i ngā hau putanga hei pēhi i te hau ki roto i ngā rango, hei whakanui ake i te pai me te mana.
– Papu Wahie: Ka tukuna te wahie mai i te tāke ki te werowero i te pēhanga teitei.
3. Ngā Āhuatanga Matua o ngā Mīhini Tīhiera
He maha ngā āhuatanga e wehewehe ana i ngā miihini tīhiera mai i ngā miihini penehīni, i runga i te hoahoa me te mahi:
– Te Whai Hua o te Wera: He pai ake te whai hua o ngā miihini tīhiera i ngā miihini penehīni, nā te mea he nui ake te ōwehenga kōpeketanga ka taea te tahunga tino pai ake.
– Te Taipana Teitei i te RPM Iti: Ka whakaputahia e ngā miihini tīhiera he taipana teitei ake i te RPM iti, ā, he mea tino pai mō ngā waka taumaha me ngā waka taumaha.
– Te Pakari me te Manawanui: Nā te mea he kaha ake te hanga o ngā wāhanga o te mīhini tīhiera kia tu atu i te pēhanga teitei, he roa ake te mau o ngā mīhini tīhiera.
– Te Whakapaunga Wahie: He iti ake te ōhanga o te wahie tīhiera i te penehīni, inā koa i raro i ngā kawenga nui me te whakamahinga tawhiti.
4. Ngā Wero me ngā Raru Noa o ngā Mīhini Tīhiera
Ahakoa he nui ngā painga o ngā miihini tīhiera, he maha atu anō ngā wero hei whakaaroaro mā rātou:
– Ngā Tukunga: Ka whakaputahia e ngā miihini tīhiera ngā tukunga NOx (hauota waikura) me ngā matūriki (ngārara), e hiahia ana ki ngā pūnaha horoi tukunga uaua ake pērā i ngā kaitahuri catalytic me te DPF (Ngā Tātari Māriki Tīhiera).
– Ngā Utu Tiaki: Ahakoa he roa ake te ora o ngā miihini tīhiera, me whai tiaki motuhake ēnei, ā, ka nui ake te utu, inā koa mō te pūnaha wahie e mahi ana i te pēhanga tino tiketike.
– Te Whakahaere i ngā Taiao Matao: Ka uaua pea te whakahaere i ngā miihini tīhiera i ngā pāmahana tino iti, me whakamahi pūnaha whakamahana tāpiri pēnei i ngā mono mura hei whakahaere i te tukanga tīmatanga.
5. Auahatanga i roto i te Hangarau Mīhini Tīhiera
I te whanaketanga o te hangarau, kei te haere tonu ngā mahi auaha a ngā miihini tīhiera hei whakapai ake i te mahi, te whai huatanga o te wahie, me te whakaiti i ngā tukunga. Ko ētahi o ngā hangarau hou ko:
– Werohanga Rerewē Noa: He pūnaha werohanga wahie e whakamahi ana i te rerewē pēhanga-teitei mō te tohatoha wahie tika ake, whai hua ake hoki i ngā pūnaha werohanga tikanga.
– Te Whakakaha Turbo me te Whakakaha Nui: Mā te whakamahi i te hangarau whakakaha turbo me te whakakaha nui, ehara i te mea ka whakanui ake i te mana anake engari ka whakanui ake hoki i te pai o te wahie mā te whakamahi i te hau putanga hei whakanui ake i te urunga o te hau ki roto i te rango.
– Te Whakaiti Whakakorikori Whiriwhiri (SCR): Hangarau hei whakaiti i ngā tukunga NOx mā te whakamahi i te wai AdBlue (urea) ka rehuhia ki roto i te hau putanga, ka hurihia hei hauota me te wai.
– Pūkaha Whakapūngao Āhua Taurangi (VGT): He pūnaha whakapūngao me te āhua taurangi e whakarerekē ana (e whakanui ana, e whakaiti ana rānei) i te rere o te hau putanga mā roto i te whakapūngao i runga i ngā hiahia o nāianei o te mīhini, e whakapai ake ana i te whai huatanga me te urupare.
Mā te mārama ki te mahi a te miihini tīhiera me ōna tikanga, ehara i te mea ka puta he māramatanga hangarau anake, engari ka puta hoki he maioha ki ngā hangarau o nāianei me ngā hangarau e whanake haere ana. Ahakoa he ahua uaua i te tīmatanga, mā te ako i ia wāhanga me ōna mātāpono mahi, ka taea e te tangata te mārama ki te mahi a te miihini tīhiera me te whai hua me te pumau. Mō te hunga e hiahia ana ki te umanga motuka, ki te umanga taumaha rānei, he mea tino nui tēnei mōhiotanga, ā, ka taea te whakamahi hei tūāpapa mō te whakapai ake i te whakamahinga me te tiaki i ngā miihini tīhiera.
