Blower capability cfm
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oldrusty
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Blower capability cfm
I am wondering with what i have read so far about the size of a vacuum motor necessary to test at 28" of depression. What i read in the 101 thread i got that with bruces digital manometers span of 16" if i wanted to test at 28" of vacuum and 450 cfm my vacuum source would actually have to be capable of 450 cfm at 44" is this correct or is my thinking flawed? If this is the case then i could see one advantage of a pitot style bench not having to have quite as big of vacuum source. help me understand this please.
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Brucepts
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Re: Blower capability cfm
Same thing happens with a pitot style flowbench you need to be able to pull the maximum differential pressure (measured as airspeed on a pitot system).
A pitot style bench uses a pipe of known diameter and you have to move the air at a specific speed so you might actually need more static pressure, depends on pipe diameter and cfm range.
Is it easier to suck air through a garden hose or straw?
Nice thing about the orifice style we already have a good idea of what is required, I don't see to many pitot style vendors talking about blower size required for specific ranges?
I've been down the pitot style flowbench road, was a staunch supporter for many years till I saw the light . . .
A pitot style bench uses a pipe of known diameter and you have to move the air at a specific speed so you might actually need more static pressure, depends on pipe diameter and cfm range.
Is it easier to suck air through a garden hose or straw?
Nice thing about the orifice style we already have a good idea of what is required, I don't see to many pitot style vendors talking about blower size required for specific ranges?
I've been down the pitot style flowbench road, was a staunch supporter for many years till I saw the light . . .
Bruce
Who . . . me? I stayed at a Holiday in Express . . .
Who . . . me? I stayed at a Holiday in Express . . .
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andykaw1
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- Location: North Italy (Malegno BS)
Re: Blower capability cfm
Brucepts wrote:Same thing happens with a pitot style flowbench you need to be able to pull the maximum differential pressure (measured as airspeed on a pitot system).
A pitot style bench uses a pipe of known diameter and you have to move the air at a specific speed so you might actually need more static pressure, depends on pipe diameter and cfm range.
Is it easier to suck air through a garden hose or straw?
Nice thing about the orifice style we already have a good idea of what is required, I don't see to many pitot style vendors talking about blower size required for specific ranges?
I've been down the pitot style flowbench road, was a staunch supporter for many years till I saw the light . . .
Great and logical answer!
Slowly I begin to understand the difference between the various type of flow bench......
Andrea