He rerekē ngā taumata matotoru o ngā wai, arā, ngā wai me ngā hau. Ko te matotoru te kaha waku i waenga i ngā ngota e hanga ana i te wai. Ka mirimiri ngā ngota e hanga ana i te wai tetahi ki tetahi i a ia e rere ana. I roto i ngā wai, ko te matotoru ka puta mai i te piripono (te kukume i waenga i ngā ngota rite). I roto i ngā hau, ko te matotoru ka puta mai i ngā tukinga i waenga i ngā ngota.
Ko ngā wai wai he māmā ake te rere, hei tauira, te wai. I tetahi atu taha, he uaua ake te rere o ngā wai matotoru, hei tauira, te hinu tunu kai, te hinu, te honi, me ētahi atu. Ka taea e koe te whakaatu i tēnei mā te ringihia te wai me te hinu tunu kai ki runga i te papa pari. Ka tere ake te rere o te wai i te hinu tunu kai, i te hinu rānei. Ko te matotoru o te wai ka whakawhirinaki hoki ki te pāmahana. Ko te teitei ake o te pāmahana o te wai, ko te iti ake o te matotoru o te wai. Hei tauira, ina paraihia e te whaea he ika i roto i te kīhini, ka wai ake te hinu tunu kai matotoru i te tīmatanga ina werahia. I tetahi atu taha, ko te teitei ake o te pāmahana o te hau, ko te matotoru ake o te hau.
Tauwehenga Matatini
Ko te matotoru o te wai e tohuhia ana e te tohu η (arā, eta). η = te tauwehenga matotoru. Nō reira, ko te taumata matotoru o te wai e whakaatuhia ana e te tauwehenga matotoru o te wai.
Ka whakatakotoria he paparanga wai angiangi ki waenganui i ngā pereti e rua. Ko te piripono te kaha kukume i waenga i ngā ngota o te momo kotahi, ko te piripono ia ko te kaha kukume i waenga i ngā ngota o ngā momo rerekē. Ka mahi te kaha piripiri i waenga i te pereti me te paparanga wai e piri ana ki te pereti (ka kukume ngā ngota wai me ngā ngota pereti tetahi ki tetahi). Ka mahi te kaha piripono i waenga i ngā paparanga wai (ka kukume ngā ngota wai tetahi ki tetahi).
I te tīmatanga, ka tū te pereti me te paparanga wai (pikitia 1). Whai muri i tēnā, ka tōia te pereti i runga ki te taha matau (pikitia 2). Kāore te pereti i raro e tōia (ka tū te pereti o raro). Ka whakatikatikaina te rahi o te kaha kume kia neke te pereti i runga ki te taha matau i te tere pumau (he pumau te v). Nā te mea he kaha piri kei waenganui i te taha o te pereti me te wāhanga o te wai e piri ana ki te pereti, ka neke hoki te wai i raro i te pereti ki te taha matau. Nā te mea he kaha piri kei waenganui i ngā ngota wai, ko te wai i neke ki te taha matau ka kukume i te wai i raro.
Ka kukume te wāhanga wai o runga i te wai o raro kia neke ki te taha matau, engari ko te wāhanga wai o raro e pupuri ana i te wai o runga, nō reira ka rerekē te tere o te wai. Ka neke te wāhanga wai o runga i te tere nui ake (v), ka neke te wai o raro i te v iti ake, ā, pērā tonu. Nō reira, ka iti ake te v. Arā, ka rerekē te tere o te paparanga wai mai i runga ki raro tae noa ki te l.
Ko te huringa o te tere o te paparanga wai (v) ka wehea e te tawhiti e puta ai te huringa (l) = v/l. E mōhiotia ana a V/l ko te pikinga tere. Ka taea e te pereti i runga te neke nā te kaha kume (F). Mō tētahi wai motuhake, ko te nui o te kaha kume e hiahiatia ana he rite tonu ki te horahanga o te wai e piri ana ki te pereti (A), te tere wai (v) me te rite whakamuri ki te tawhiti l. Mā te pāngarau, ka taea te tuhi penei:
Tātai tauwehenga matotoru
I mua ake nei, i whakamāramahia ko ngā wai angiangi he māmā ake te rere, engari ko ngā wai matotoru he uaua ake te rere. Ko te matotoru o te wai ka whakaatuhia e tōna tauwehenga matotoru. Ko te matotoru o te wai, ko te nui ake o te kaha kume e hiahiatia ana. I tēnei take, he rite tonu te kaha kume ki te tauwehenga matotoru. Mā te pāngarau, ka taea te tuhi penei:
Ngā Mōhiohio:
η = Tauwehenga matotoru
F = Te Kaha
l = Tawhiti
A = Horahanga mata
v = Tere
∝ = rite
Ko te Pūnaha Wāhanga o te Ao (SI) mō te tauwehenga matotoru ko Ns/m2 = Pa.s (hekona pascal). Ko te waeine CGS (henimita karamu hekona) mō te tauwehenga matotoru ko dyn.s/cm2 = tū pakari (P). He maha hoki ngā wā ka whakaatuhia te matotoru ki roto i te centipoise (cP). 1 cP = 1/100 P. E whakamahia ana te waeine tū pakari hei maumaharatanga ki te kaipūtaiao Wīwī, ki a Jean Louis Marie Poiseuille kua mate (pwa-zoo-yuh).
1 tūnga = 1 dyn . s/cm2 = 10-1 Ns/m2
