|
Thread Number: 36311
/ Tag: Brand New Vacuum Cleaners
Airflow v Airspeed |
[Down to Last] |  |
| Post# 389358 3/29/2018 at 04:53 (2,218 days old) by vacfan1982 (Cardiff) | ||
Can someone explain to me in laymans terms the difference between airflow and airspeed and which is more important to get clean carpets?
Here's an analogy. A wide river could have lots of flow but the flow is slow and you could safely walk across it. A narrow river could have less flow but it is flowing fast, if you tried to walk across this river you would be swept away. So is it airspeed (velocity) That is more important than airflow? This is complicated science for me haha | ||
| Post# 389359 , Reply# 1 3/29/2018 at 05:21 (2,218 days old) by vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389362 , Reply# 3 3/29/2018 at 09:09 (2,218 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389363 , Reply# 4 3/29/2018 at 09:11 (2,218 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389365 , Reply# 5 3/29/2018 at 09:13 (2,218 days old) by Kirbysthebest (Midwest) | ||
|
Headache?? Take two Vicoden and call me tomorrow. | ||
| Post# 389367 , Reply# 6 3/29/2018 at 09:19 (2,218 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389373 , Reply# 7 3/29/2018 at 10:50 (2,218 days old) by Vaclab (Pickerington, Ohio) | ||
I see the two like this... | ||
| Post# 389374 , Reply# 8 3/29/2018 at 11:00 (2,218 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389409 , Reply# 9 3/29/2018 at 21:05 (2,217 days old) by vaclab (Pickerington, Ohio) | ||
|
Yes, Airspeed Over an Area is The Most Important Thing
in addition to agitation. Remember, you can't have airspeed by itself. The speed of the air will have some sort area (i.e. nozzle opening) to flow through.
For comparison, a Dyson DC65 has 30 MPH air with the nozzle removed (ball bottom) and a Kirby Sentria II has 77 MPH air with the nozzle removed (on low speed). The Kirby easily deep cleans through a pile carpet while a typical bag-less machine can't. Bill | ||
| Post# 389428 , Reply# 10 3/30/2018 at 00:44 (2,217 days old) by vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389433 , Reply# 12 3/30/2018 at 07:48 (2,217 days old) by Vaclab (Pickerington, Ohio) | ||
|
Mike, I must disagree with you on this one
My entire youtube channel consistently shows that fine dust pickup requires high airflow coupled with a reasonable amount of agitation. High suction is a lie perpetuated by the bagless manufacturers in order to make their machines seem as good as dirty air machines.
Case(s) in point: Hoover Convertible with 25" of lift but 107 nozzle CFM. Cleans fine dust and grit very well. Next, a typical Kirby with 34" of lift and 120-137 nozzle CFM. Cleans so well, it easily cleans the carpet under the carpet, when the carpet is flow through of course. With my extensive testing, I will not "drink the suction koolaid". Suction is good for lifting large objects, like bowling balls, bolts, pool balls and probably two by fours, not dust and grit though. | ||
| Post# 389434 , Reply# 13 3/30/2018 at 07:53 (2,217 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389456 , Reply# 14 3/30/2018 at 12:06 (2,217 days old) by sptyks (Skowhegan, Maine) | ||
Suction vs airflow | ||
| Post# 389457 , Reply# 15 3/30/2018 at 12:18 (2,217 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389462 , Reply# 16 3/30/2018 at 13:53 (2,217 days old) by Vaclab (Pickerington, Ohio) | ||
|
Airflow with relatively low suction
Can pick up houses. Think of a tornado. They are rated by wind speed, not suction. Also introducing wind driven tools changes the equation quite a bit. You are now making the air do work by forcing it to spin something.
Non mechanical tools work better with high airflow, not high suction. I have many videos showing this repeatedly. Maybe I should make another one... | ||
| Post# 389463 , Reply# 17 3/30/2018 at 13:57 (2,217 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Post# 389466 , Reply# 18 3/30/2018 at 14:22 (2,216 days old) by Vaclab (Pickerington, Ohio) | ||
|
Ah, now I'm seeing where you're coming from I think
The strength you feel is a pressure (suction). If you need to force air to do work (spin something) or traverse long distances (say 50 or 100 feet), then higher suction will maintain more airflow. BUT, if your airflow is restricted too much, like cyclones, air driven tools, etc., then there is not much airflow remaining to pickup dust anyway. Turbine tools reduce airflow horribly just like cyclones unfortunately.
A Kirby Sentria 2 has 120 CFM at the end of the hose, but only 40" of lift. Standard non-Kirby air driven tools will work, but you won't get the best performance due to low suction. See my turbine tools versus suction video for more info. Bill | ||
| Post# 389467 , Reply# 19 3/30/2018 at 14:26 (2,216 days old) by Vacfan1982 (Cardiff) | ||
|
| ||
| Forum Index: | 
| Other Forums: |
|
|
|
|
|
Comes to the Rescue!
