Thread Number: 38411
/ Tag: Brand New Vacuum Cleaners
Tapered Hose on Miele Blizzard Bagless Canister Vac |
[Down to Last] |
Post# 408821   4/28/2019 at 10:22 (1,822 days old) by eurekaprince (Montreal, Canada)   |   | |
Checkrate/Likes
 
1    
Our friend Ibaisaic Sensotronic in the UK has posted a new video demonstrating the Miele Blizzard canister vac. One strange thing with this vac is that the tapered hose needs to be installed with the wider end near the handle, rather than on the canister end.
Why would Miele do this? It’s seems to go against the idea that the airflow will speed up at the hose end, like a crevice tool, or a cyclone. The way the Blizzard hose is installed, it would seem prone to clogging as the hose could accomodate a large piece of debris at the handle end but get stuck in the narrower part of the hose closer to the canister. Why would this design work better than those hoses that widen closer to the canister? Am I missing something here? |
Post# 408822 , Reply# 1   4/28/2019 at 10:40 (1,822 days old) by Blackheart (North Dakota)   |   | |
Checkrate/Likes
 
     
|
Post# 408827 , Reply# 3   4/28/2019 at 11:09 (1,822 days old) by eurekaprince (Montreal, Canada)   |   | |
Checkrate/Likes
 
1    
|
Post# 408828 , Reply# 4   4/28/2019 at 11:25 (1,822 days old) by Blackheart (North Dakota)   |   | |
Checkrate/Likes
 
     
|
Post# 408830 , Reply# 5   4/28/2019 at 12:20 (1,822 days old) by luxflairguy (Wilmington, NC)   |   | |
Checkrate/Likes
 
     
Total ignorance..! G |
Post# 408832 , Reply# 6   4/28/2019 at 12:25 (1,822 days old) by luxflairguy (Wilmington, NC)   |   | |
Checkrate/Likes
 
     
My opeing line came off the fingers wrong! It should have "That's just DUMB! Oppps! Old man here! |
Post# 408883 , Reply# 7   4/29/2019 at 16:27 (1,821 days old) by Blackheart (North Dakota)   |   | |
Checkrate/Likes
 
     
After giving it some thought the only reason I can only see one reason for the reversed taper.
Using the same body. If it were wider at the machine end the inlet and the piping leading to the bin would have to be as wide if not wider than the hose. It's been my experience that tapered hoses offer performance advantages over uniform diameter ones at least if the uniform is equal to the narrowest diameter on the taper. I saw that on my lindhaus Aria, it originally had a tapered hose which allowed it to read 7.5 on the baird meter but a replacement non tapered 1.25" hose brought the meter down to 5.5. which is about a 12 CFM difference. I'm quite curious if the reverse taper effects a machine's airflow as much as the standard. To test this i'll remove the cuffs from my Numatic Henry and and then use both the standard and 1.25" machine ends which will allow me to flip the taper. It'll be interesting but I have a feeling the standard taper will work better due to the greater resistance being encountered later than sooner. |
Post# 408886 , Reply# 8   4/29/2019 at 17:40 (1,821 days old) by Blackheart (North Dakota)   |   | |
Checkrate/Likes
 
     
Here's what I did, I removed the tool end cuff from the hose and measured the airflow in it's normal configuration I got 4252 FPM or 110.97 CFM I normally get about 108 with the cuff attached.
Then I got out my 1.25 machine end and attached the hose backwards to the machine like the Miele Design and I got 3937 FPM or 102.75 CFM Now here's where things got interesting. I took a crushproof extension hose that I have around and cut it to about the same length as the OEM hose this hose is a consistent diameter all the way through. It actually got a higher CFM than the inversed taper measuring in at 3994 I did even see it jump to 4000 once or twice I'm rathered confused by this you'd think the inverted taper having a larger area where in theory there should be less resistance to flow would have the advantage. I guess with it being a different make the materials or even the design of it may be smoother flowing than the OEM hose. TL:DR The standard taper works better than an inverted one. Taper: 110.97 CFM Inverted Taper: 102.75 Standard hose: 104.24 |
Post# 408894 , Reply# 9   4/29/2019 at 21:15 (1,821 days old) by eurekaprince (Montreal, Canada)   |   | |
Checkrate/Likes
 
     
|
Post# 408903 , Reply# 10   4/30/2019 at 00:37 (1,821 days old) by vacuumdevil (Vacuum Hell )   |   | |
Checkrate/Likes
 
     
So nobody's familiar with the concept of velocity stacks?
Here's a link to the concept. CLICK HERE TO GO TO vacuumdevil's LINK |
Post# 408907 , Reply# 11   4/30/2019 at 04:14 (1,820 days old) by Blackheart (North Dakota)   |   | |
Checkrate/Likes
 
     
|
Post# 408910 , Reply# 12   4/30/2019 at 05:40 (1,820 days old) by eurekaprince (Montreal, Canada)   |   | |
Checkrate/Likes
 
     
Thanks for that clarification...makes sense to me. Though I studied physics in college and high school, I can’t remember all the details about centrifugal forces, etc. All I know is that when I attach a crevice tool to any vacuum hose, the sucking power increases at the tip of the attachment, even though the motor power has not been increased.
So it still mystifies me as to why Miele would design a “reverse tapered” hose for the Blizzard. I’ll have to watch the above video to see if it’s explained there...:-) |