# Two fans strapped together - what happens? **URL:** \ **Category:** Factual Questions\ **Created:** [June 26, 2018, 1:35pm UTC](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766 "2018-06-26T13:35:02Z")\ **Posts on this page:** 5\ **Page:** 2
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [June 27, 2018, 11:52pm UTC](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766/21 "2018-06-27T23:52:04Z")
> [@Machine\_Elf](#): > > Bottom line, the fans will still generate a pressure drop in the enclosure, even if they aren’t moving any air. No doubt. But the measured pressure drop in the enclosure is quite small: in the “stalled” configuration, a fan cannot create as much pressure differential as it can in the “unstalled” configuration. If, (I have no reason to disagree), the normal operation of a normal fan blade is “half stalled”, then the difference between half stalled and fully stalled is, it would appear, even more than when an airplane wing moves from normal to half-stalled. ---
**Author:** ![Fiendish\_Astronaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fiendish_astronaut/32/3295_2.png) [@Fiendish\_Astronaut](https://boards.straightdope.com/u/Fiendish_Astronaut)\ **Post date:** [June 28, 2018, 11:25am UTC](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766/22 "2018-06-28T11:25:35Z")
I love this board. Thanks for the answers - even if the answer to the question seems simple, the rabbit holes are where the fun is had. ---
**Author:** ![Shodan](https://avatars.discourse-cdn.com/v4/letter/s/9f8e36/32.png) [@Shodan](https://boards.straightdope.com/u/Shodan)\ **Post date:** [June 28, 2018, 12:43pm UTC](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766/23 "2018-06-28T12:43:18Z")
> [@Fiendish\_Astronaut](#): > > … the rabbit holes are where the fun is had. [Assume two rabbits…](https://plus.maths.org/content/fibonacci-sequence-brief-introduction) Regards, Shodan ---
**Author:** ![ataraxy22](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ataraxy22/32/307_2.png) [@ataraxy22](https://boards.straightdope.com/u/ataraxy22)\ **Post date:** [June 28, 2018, 1:23pm UTC](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766/24 "2018-06-28T13:23:49Z")
Wouldn’t the correct answer be dependent on whether the fans both supported the same team or rival teams? Sent from my SM-G930V using Tapatalk ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [June 28, 2018, 1:47pm UTC](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766/25 "2018-06-28T13:47:48Z")
> [@EdelweissPirate;21046352](#): > > but it will be equal to the volume of air that gets sucked in past the blades by the low pressure zone inside the cylinder. No air gets “sucked”, except by gravity or if its ionised and affected by an electrical field, or something in the force fields. Say you have a perfect flask, with a perfect vacuum inside. Now you are inside another perfect vacuum, but there is a piece of paper right in front of the opening to the flash. Now open the flask in such a way that its open, except that the paper blocks the opening. Does it suck the paper in ? No. the flask is not sucking ! The paper would have to be be pushed in. The low pressure zone inside the two fan blades would go to perfect vacuum, but the atmosphere pressure PUSHES air in faster and faster with rate of air flow increasing difference in pressure… [Previous page](https://boards.straightdope.com/t/two-fans-strapped-together-what-happens/816766.md?page=1)