Sucking better than Blowing ?
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Sucking better than Blowing ?
Good title post eh ?
During this warm spell my thoughts always turn to keeping cool.
The Question ? Can these cheap Chinese ceiling fans be reversed ? ie: to suck the cold air upwards, rather
than them pushing hot air down.
I have three expensive fans that do both summertime anticlockwise winter clockwise .
Answers on a postcard or just a post, cheers.....
Ps: I ask because I have just had 8 calls from Souk.com
telling me my two new oscillating motion fans have arrived @ Gezira Gdns. (bakshesh)
During this warm spell my thoughts always turn to keeping cool.
The Question ? Can these cheap Chinese ceiling fans be reversed ? ie: to suck the cold air upwards, rather
than them pushing hot air down.
I have three expensive fans that do both summertime anticlockwise winter clockwise .
Answers on a postcard or just a post, cheers.....
Ps: I ask because I have just had 8 calls from Souk.com
telling me my two new oscillating motion fans have arrived @ Gezira Gdns. (bakshesh)
"The Salvation of Mankind lies in making everything the responsibility of All"
Sophocles.
Sophocles.
- Horus
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Re: Sucking better than Blowing ?
If your asking a serious question then the answer would be that a ceiling fan with fixed blades would be directional and as such the motor cannot be reversed being single phase, but the main thing would be the blade angle which would be the wrong shape if going in reverse.
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Re: Sucking better than Blowing ?
If you can flip the fan over, it will solve your problem.
This may involve a certain amount of screwing to translate the blowing into sucking
This may involve a certain amount of screwing to translate the blowing into sucking
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Re: Sucking better than Blowing ?
You could always stick it on a pole upside down with a trailing lead across the floornewcastle wrote:If you can flip the fan over, it will solve your problem.
This may involve a certain amount of screwing to translate the blowing into sucking
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Re: Sucking better than Blowing ?
Iv'e tried many forms of the blade angles, doesn't work.
How I know ? I use smoke to follow the air currents around the house...
The mud ceilings in these adobe houses normally also have a high-up hole to let out the hot air,
mine contains a very large voltage stabilizer.....
Ps: This subject is a complicated one: Quote...
"Ceiling fans do not move air in the room in a homogenous manner. Bassiouny and Korah in 2011 studied the airflow patterns in a room due to a single rotating ceiling fan. They found that airflow was the lowest at two locations: at the ceiling fan hub (i.e., fan center) and at the fan blade tip. It is somewhere between the fan center and fan blade tip that airflow was the highest.
So, if we plot the airflow velocity (speed) at various distances along the fan blade length, we would observe that the airflow generated by a ceiling fan would increase from the fan center, reach maximum at somewhere midway of the fan blade length, and then decline moving towards the fan blade tip. This change in airflow velocity which rises then falls along the fan blade length is the so-called humped airflow profile.
Humped airflow profile, where airflow velocity increases from the fan center before reaching maximum (i.e., hump) at about midway of the blade length, then decreases along the blade length (Schmidth and patterson, 2001)
All ceiling fans display the so-called humped airflow profile, where airflow velocity increases from the fan center before reaching maximum (i.e., hump) at about midway of the blade length, then decreases farther along the blade length (Schmidt and Patterson, 2001).
'Simples ? I don't think so....
How I know ? I use smoke to follow the air currents around the house...
The mud ceilings in these adobe houses normally also have a high-up hole to let out the hot air,
mine contains a very large voltage stabilizer.....
Ps: This subject is a complicated one: Quote...
"Ceiling fans do not move air in the room in a homogenous manner. Bassiouny and Korah in 2011 studied the airflow patterns in a room due to a single rotating ceiling fan. They found that airflow was the lowest at two locations: at the ceiling fan hub (i.e., fan center) and at the fan blade tip. It is somewhere between the fan center and fan blade tip that airflow was the highest.
So, if we plot the airflow velocity (speed) at various distances along the fan blade length, we would observe that the airflow generated by a ceiling fan would increase from the fan center, reach maximum at somewhere midway of the fan blade length, and then decline moving towards the fan blade tip. This change in airflow velocity which rises then falls along the fan blade length is the so-called humped airflow profile.
Humped airflow profile, where airflow velocity increases from the fan center before reaching maximum (i.e., hump) at about midway of the blade length, then decreases along the blade length (Schmidth and patterson, 2001)
All ceiling fans display the so-called humped airflow profile, where airflow velocity increases from the fan center before reaching maximum (i.e., hump) at about midway of the blade length, then decreases farther along the blade length (Schmidt and Patterson, 2001).
'Simples ? I don't think so....
"The Salvation of Mankind lies in making everything the responsibility of All"
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Re: Sucking better than Blowing ?
In one of the apartments I stayed in all the fans had the usual looking box with a knob which you turned clockwise to increase the speed of the fan, except these boxes had the knob in the centre position (which was off) If you turned it right it blew down air, turned it left and it sucked up the air, the fans looked no different to the normal fans you see in most apartments.
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Re: Sucking better than Blowing ?
As the Winter here fast approaches....on a sunny Monday and only 42oC.
So as the "Nile fed plunge healing pool™ pending, is turning chilly Here, Is the 'mark 4 Winter water heater.....
Note the bubbles it gets to a pleasant 38oC in 24 hrs and stays hot for 10 hours.
(Obviously! not connected in this picture)
Plus + I have a very clever Chinese Disco Ball that plays soothing Ambient 8gig memory stick
though a 'newly attached car speaker. 300le souk.com 'thats the light not the speaker!
Axel of JJ's Bar reckons they are also sound to light, "chill Winstone chill...
So The Dr is popping back to the 'Smoke next week,
hopefully rain, beer, smog, bacon butties, black pudding, a chilled bottle of Chevalier-Montrachet
and people who ignore a cheery morning "AsSalam Alaikum" .....
"Love London Love Life" Who said that ?
So as the "Nile fed plunge healing pool™ pending, is turning chilly Here, Is the 'mark 4 Winter water heater.....
Note the bubbles it gets to a pleasant 38oC in 24 hrs and stays hot for 10 hours.
(Obviously! not connected in this picture)
Plus + I have a very clever Chinese Disco Ball that plays soothing Ambient 8gig memory stick
though a 'newly attached car speaker. 300le souk.com 'thats the light not the speaker!
Axel of JJ's Bar reckons they are also sound to light, "chill Winstone chill...
So The Dr is popping back to the 'Smoke next week,
hopefully rain, beer, smog, bacon butties, black pudding, a chilled bottle of Chevalier-Montrachet
and people who ignore a cheery morning "AsSalam Alaikum" .....
"Love London Love Life" Who said that ?
"The Salvation of Mankind lies in making everything the responsibility of All"
Sophocles.
Sophocles.
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Re: Sucking better than Blowing ?
Try looking for a proper fan control box with speeds and fan direction on. I used them many years ago for Expelair extractor fans, so would imagine that they would do the same for ceiling fans. Google Expelair Fan Controllers.
Of course if it was 3 phase then it would just be a matter of changing 2 of the phases around.
Of course if it was 3 phase then it would just be a matter of changing 2 of the phases around.
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Re: Sucking better than Blowing ?
Hmm! the control box. If it was that simple it might just have slipped under my radar..
Sadly not, it's the motor rather than the control box that determines it's direction.
A good try to say the least, don't give up the day job...
"Marks out of 10 = 2 for effort could do better...
Sadly not, it's the motor rather than the control box that determines it's direction.
A good try to say the least, don't give up the day job...
"Marks out of 10 = 2 for effort could do better...
"The Salvation of Mankind lies in making everything the responsibility of All"
Sophocles.
Sophocles.
- Major Thom
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Re: Sucking better than Blowing ?
The Expelair control unit has all the works in it and takes over the control of the motor on the fan unit Dr. The controller itself is more costly than the fan in most cases, but does the job by reversing electrical fields, and a rheostat to control the speed.
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Re: Sucking better than Blowing ?
Far to complicated an operation for me to perform....
https://woodgears.ca/motors/reversing.html
https://woodgears.ca/motors/reversing.html
"The Salvation of Mankind lies in making everything the responsibility of All"
Sophocles.
Sophocles.