I checked the previous questions on the forum, but I still can’t understand it. The following is my personal understanding of backpressure; what about the experts?
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This post was last edited by HaiChuanXiaoDangJia on 2020-6-29 at 10:42. I often come across expressions like “system back pressure XXX MPa”; generally speaking, the back pressure of a turbine refers to the pressure of the exhaust gas after the steam has done its work. But the use of the word \"back\" confuses me. Look at the diagram and the text: \"When the back pressure at the outlet of the proportioning mixer is greater than zero, there should be a mechanism on the suction pipe to prevent water from flowing back into the foam liquid tank (a one-way valve).\" ”Based on what’s mentioned in the \"Fire Engineer Textbook,\" I’m confused. Taking this proportioning mixer as an example, if the back pressure is greater than zero, it means there is pressure at the outlet of the proportioning mixer that can hold back the water, right? So why would there be a risk of water flowing back into the foam liquid tank? Is back pressure a force at the outlet, a force that prevents the fluid from exiting? Is that what you mean?
Add it to a container with a pressure of 1 Ma; if the outlet pressure of the centrifugal pump is only 0.5 MPa, can it be pumped in?
Could you explain it more clearly, sir?
Got it, it’s the outlet resistance
What’s there to say about this? It’s just like blowing up a balloon: if the pressure inside is high, you need to generate even greater pressure in order to blow air in; otherwise, the air inside will escape
Hello, may I ask if the pressure in this \"foam liquid storage tank\" is equal to atmospheric pressure? There should be an intake pipe connected to the atmosphere, right? Please give me some advice. Thank you!
:victory: Thank you!
In my opinion, it’s just an ordinary container at normal pressure; it must have some opening or valve that connects to the atmosphere, otherwise nothing can be drawn out
This post was last edited by CHANGBAISHI on 2020-6-30 at 15:46. Oh, once you understand the principle, there’s no need to worry about terms like \"back pressure\". As development progresses, one will encounter more such terms. Actually, these words are just used to express something; once you understand it, that’s enough. For reference. Oh, Baidu provides an explanation for the term “back pressure”; given my limited knowledge, I’m not confused by it; P
Due to my limited skills, there is nothing I don’t understand. .