Okwu Mmalite nke okwu mgbapụta nkịtị (6) – Ozizi cavitation mgbapụta

Cavitation nke mgbapụta: Ozizi na Ngụkọta

Nkọwa nke ihe gbasara cavitation
Nrụgide nke vaporization mmiri mmiri bụ nrụgide vaporization nke mmiri mmiri (nrụgide vapor juru). Nrụgide vaporization nke mmiri mmiri na-ejikọta ya na okpomọkụ. Ka okpomọkụ dị elu, otú ahụ ka nrụgide vaporization na-abawanye. Nrụgide vaporization nke mmiri dị ọcha na okpomọkụ ụlọ nke 20℃ bụ 233.8Pa. Ọ bụ ezie na nrụgide vaporization nke mmiri na 100℃ bụ 101296Pa. Ya mere, mmiri dị ọcha na okpomọkụ ụlọ (20℃) na-amalite vaporization mgbe nrụgide ahụ dara na 233.8Pa.
Mgbe nrụgide nke mmiri mmiri belatara ruo na nrụgide vaporization n'otu okpomọkụ, mmiri mmiri ahụ ga-emepụta afụ, nke a na-akpọ cavitation. Agbanyeghị, uzuoku dị na afụ ahụ abụghị uzuoku kpamkpam, kama ọ nwekwara gas (karịsịa ikuku) n'ụdị mgbaze ma ọ bụ nucleus.
Mgbe afụfụ na-apụta n'oge cavitation na-eruba n'elu nrụgide dị elu, olu ha na-ebelata ma ọbụna gbawaa. Ihe a na-akpọ cavitation daa n'ime mmiri mmiri n'ihi mmụba nrụgide.

Ihe na-eme ka cavitation dị na mgbapụta ahụ
Mgbe ọkpọkọ ahụ na-arụ ọrụ, ọ bụrụ na mpaghara mpaghara nke akụkụ ya jupụtara (na-abụkarị n'azụ ntinye nke agụba impeller). N'ihi ihe ụfọdụ, mgbe nrụgide zuru oke nke mmiri a na-agbapụta dara na nrụgide vaporization na okpomọkụ dị ugbu a, mmiri ahụ na-amalite ịgbọpụta ebe ahụ, na-emepụta uzuoku ma na-akpụ afụ. Afụkọ ndị a na-asọga n'ihu na mmiri ahụ, mgbe ha ruru nrụgide dị elu ụfọdụ, mmiri nrụgide dị elu gburugburu afụkọ ndị ahụ na-amanye afụkọ ndị ahụ ka ha daa nke ọma ma ọbụna gbawaa. Mgbe afụkọ ahụ gbawara, ihe ndị dị n'ime mmiri ga-ejupụta oghere ahụ n'ọsọ dị elu ma kụọ ibe ha iji mepụta hama mmiri. Ihe a ga-eme ka ihe ndị dị n'elu ọkụ mebie mgbe ọ mere na mgbidi siri ike.
Usoro a bụ usoro cavitation mgbapụta.

Mmetụta nke cavitation mgbapụta
Mee mkpọtụ na mkpọtụ
Mmebi nke ihe ndị na-agafe agafe
Mmebi arụmọrụ

a

Mgbapụta cavitation nhazi bụ isi
A na-akpọkwa NPSHr-Pum cavitation allowance dị mkpa, a na-akpọkwa ya isi dị mkpa dị na mba ọzọ.
NPSHa- A na-akpọkwa ikike cavitation nke ngwaọrụ ahụ onyinye cavitation dị irè, nke ngwaọrụ ịmịnye na-enye. Ka NPSHA na-abawanye, otú ahụ ka ọ ga-adị obere ka ọkpọkọ ahụ ga-enwe cavitation. NPSHa na-ebelata ka okporo ụzọ na-abawanye.

b

Mmekọrịta dị n'etiti NPSHa na NPSHr mgbe mmiri na-agbanwe

Usoro ngụkọ nke cavitation ngwaọrụ

hg=Pc/ρg-hc-Pv/ρg-[NPSH]

[NPSH] -Nkwenye cavitation enwere ike inye ikike
[NPSH] = (1.1 ~ 1.5) NPSHr

Mgbe ọnụego mmiri ahụ buru ibu, were nnukwu uru, mgbe ọnụego mmiri ahụ pere mpe, were obere uru.


Oge ozi: Jenụwarị-22-2024