I don't expect that anyone here has done this before, but I want your opinion on this anyways.
If I were to stage several radial fans as illustrated in the pic would it actually increase the maximum pressure on the output end by a non marginal amount?
It would increase pressure but not as efficiently as selecting a way higher rpm radial fan. Cascading fans works okay with radial fans but is not the most efficient means to increase pressure. Without knowing the fan specs it would be hard to give any figures as to pressure gain.
Fans like that don't compress air to any reasonable extent. This is why strapping a big electric fan to the intake of your car does absolutely nothing, but attaching a supercharger or turbocharger that has an impeller rotating at several tens of thousands of rpm does.
>>900630
centrifugal pumps can be stacked in series to increase output pressure.
air is a fluid.
i'm not saying it will work but its probably worth a shout op.
>>900630
Putting two or more fans in series allows it to maintain its airflow better when resistance occurs; Filters, Cooling fins or Duct loss.
You have twice the number of blades pushing the same air, wich does increase pressure. it will be marginal though
But Depending on the application it might be enough.
>>900633
A compressor is not a fan anon.
>>900643
So 2 Fans in series results in ~double the static pressure at same airflow? Sounds pretty much like what I hoped for.
>>900649
well considering what everyone pointed out, they do not increase pressure alot. but it does stack up.
using the 2w example wich is 2,5 millibar
if you were to put 10 in series, you would get around 25millibars. the atmosphere is ~1000millibars for reference
not sure about the efficiency, but im guessing anywhere between 50 and 90%
>>900634
Small channels?
why not use one intake and one exhaust fan
>>900630
of course. Youre pressurizing already pressurized air. Unless the next fan doesnt have enough power to furtherbincrease the pressure it will rise. It is how jet engines work. However you dont need to do this. Simply put a divergent nozzle on the end and the pressure will automatically drop. Also as others have said those little electric fans dont really rise pressure that much. Best to design your own and power it with petrol. Google "centrifugal compressor" they have exxtras like guide vanes and a expanding volute to decrease pressure.
This is the most retarded thread I've seen in a while.
If for example you have 1, 2 or even 3 fans, all capable of the same amount of air movement, do you think having them running in series, you're going to magically have an increase in performance?
No. You're just introducing drag and restriction. I'd proabably expect lower performance.
Two fans working side by side (parallel) would increase air movement.
>>900662
sorry i mean the pressure will rise through the expansion nozzle
>>900663
if you are going to call others retarded at least know what you are talking about. First of all he wants to increase pressure not air movement and secondly seeing as series staging of compressors is standard in industry i doubt its retarded.
>>900663
u dumb
blower creates high pressure at output and low pressure at intake.
stacking means previous blower has lower resistance and blower after has higher pressure to begin with.
pressure and volume are different.
>parallel increase air movement
if you mean volume then yes congratulations one sensible thing.
>>900665
>>900666
>fan
>compressor
One of these is not like the other.
The increase in pressure at the output of one fan is bottle necked by the low pressure by design at the input of the other. Unless the second, third etc. fans are being driven at an increased ratio and more air being driven in to it (larger fan needed at the first stage) you wont increase pressure either.
>Two fans in series are normally rated as a single unit in order for AMCA rating definitions and practices to apply. To simplify selection and control, two fans of the same size are typically used with the required flow rate defined by the inlet conditions of the first fan. The combined total pressure across both fans will be the sum of the individual total pressure of each fan. Total pressures are used instead of static pressure because the fans can actually be different sizes and a change in fan or connecting duct areas has an influence upon static pressure values.
There's a reason most systems of air movement (being for high or low pressure applications) use only one fan.
If you see secondary fancy within systems its either for redundancy or increased air flow where size of the unit is limitedm and again, these wont be in 'series' unless it is purely for redundancy or if one may have to be run in reverse.
>in b4 that's axial, not radial
Irrelevant. Same bottle-necks apply.
>>900672
Yes and i explained this in mybresponse to OP, he needs to use dedicated centrifugal compressors and not electric fans. Nevertheless calling him retarded is rude and uncalled for because his concept is sound it just needs dedicated compressors to work. Nobody likes an obnoxious pseudo know it all, how about you fuck off and learn some manners while youre gone?
What is your goal op?
There may be a better way.
>>901332
Cooling solution for a tight spot. I don't have enough space for air channels bigger than 5*5mm / 1/5*1/5" so I need something that still gets a decent airflow at that size.
>>901454
Why can't you use heatpipes?
>>901501
Can't connect anything to the thing to cool. Liquids wont work for this either.
>>901543
>So why can't you use heatpipes with a radiator on both ends?
Because that would be overcomplicated and would have way less effect than air.
>Why the secrecy?
It's nothing secret. Just a FDM machine. That doesn't realy ad much to the original question though.
>>900663
Why does Nilfisk add more heads to their commercial vacuums if adding more fans won't work better?
just buy a delta.
>>902642
They are side by side, not in series. Learn 2 reading comprehension.
>>900649
Actually no. Pumps and fans in series increases the ability to perform under load. If you want more power you have to set them up in parallel.
>>902723
>Pumps and fans in series increases the ability to perform under load
Well thats the essence of what I want.
>>902723
so it's like the opposite of electric?
>>902852
and that exactly will happen.
loads of people in here are mistaking compressors for fans
>>900633
Is it considered an impellor in a turbo and a propellor in a super?
>>902892
Good question.
I've never heard of a propeller used as a term on either device.
Usually you hear compressor.
>>900633
turbochargers spin to a maximum of 150-200krpm anon...
as for fans spin to like 3000rpm
also fans just use a rough casting as shroud or housing with huge tolerances, where turbines are machined to have a <0.1mm gap.
>>902892
turbochargers use a centrifugal compressor wheel driven by a turbine, as superchargers use a mechanically driven screw compressor, or roots blowers.
>to get your question answered on the internet, you dont post the question. You post the wrong answer instead.
even google can teach you this.
>>900630
No.
HVAC Tech here.
>>902928
So no impellers or propellers?
I tried that once but couldn't handle the hate
my commercial wall vac system has them in a parallel setup, just went to look. has two fans.
