Why is airflow always measured?

[Vacuum Facts]

Cleaning path is too often overlooked. Even just a drop from 12" to 10" will make the job take at least 20% longer. And I don't even know how you could clean efficiently with a head that leaves an uncleaned path in the middle

Unswept paths are poor. Any machine that uses a drive belt or rug strips also suffers from it. Also, unswept paths at edges where motors sit. There is advantage to partially overlapping cleaning path on any machine though.

 

[Hatsuwr]

Unswept paths are poor. Any machine that uses a drive belt or rug strips also suffers from it. There is advantage to partially overlapping cleaning path on any machine though.

We are talking about cleaned path width, which is different than the cleaner head width.

Continuous roller brushes that are side driven don't suffer from an interrupted cleaning path.

And yes, you should be overlapping cleaning paths at least slightly, and doing so creates a larger addition to cleaning time for heads with a smaller cleaning path.

 

[Vacuum Facts]

Ultimately, what counts is measured cleaning performance, since it captures every variable and design choice possible. Very few measure it reputably. There's also no substitute for industry test standards and beyond, but they're very hard to conduct without a genuinely professional lab and a lot of money and time.

 

[Hatsuwr]

Ultimately, what counts is measured cleaning performance, since it captures every variable and design choice possible. Very few measure it reputably. There's also no substitute for industry test standards and beyond, but they're very hard to conduct without a genuinely professional lab and a lot of money and time.

Well, ignoring things like reliability, ease of use, cost, etc. considering the topic of the thread, I'd argue that what ultimately matters is the time to complete the cleaning job to a certain standard.

Good quality vacuums are able to do single pass cleaning for normal applications, so anything that requires more than one pass over a given path can be dismissed in my opinion. From what remains, cleaning time will be a factor of cleaned path width and the speed that the head can be moved while still cleaning effectively.

 

[Absolute Rainbow]

We are talking about cleaned path width, which is different than the cleaner head width.

Continuous roller brushes that are side driven don't suffer from an interrupted cleaning path.

And yes, you should be overlapping cleaning paths at least slightly, and doing so creates a larger addition to cleaning time for heads with a smaller cleaning path.

Which is definitely part of a controlled and methodical cleaning method. You have to overlap some, not only to eliminate unswept paths but also increase cleaning effectiveness.

 

[Vacuum Facts]

Well, ignoring things like reliability, ease of use, cost, etc. considering the topic of the thread, I'd argue that what ultimately matters is the time to complete the cleaning job to a certain standard.

Good quality vacuums are able to do single pass cleaning for normal applications, so anything that requires more than one pass over a given path can be dismissed in my opinion. From what remains, cleaning time will be a factor of cleaned path width and the speed that the head can be moved while still cleaning effectively.

Yeah. I meant when considering the cleaner head. For the overall product, three things matter: performance, east of use (both of these affect time to do the job), and environmental impact. This is how I review all machines. Good machines can do most of the job in one pass with 50% overlap (on real-world mess levels) and take the minimum energy to do it without wastage and blasting at full power all the time when not needed. The additional time from a narrower head isn't that significant from experience, since total cleaning time isn't that great in any one cleaning session, and narrower heads can get into places that wide heads can't and would otherwise need time and hassle preparing other attachments to reach. And then there's all the setup of faffing with cords and plugging in, rewinding etc. Screwing around finding bags, taking the old one out, binning it, putting a new one in, closing up etc. All adds up. Poor cleaners are cumbersome to use and brute force performance sloppily. Just 240 W of power drain is all that's needed for nominal cleaning from the data I have now.

 

[Hatsuwr]

I think your overall list of factors could use a bit of expansion, but environmental impact is a bit silly to talk about in the context of using battery powered appliances in a residential setting. Batteries are used for portability, not for performance or environmental friendliness lol. Battery powered appliances almost universally will have more of a negative impact than their equal performance/class mains-powered counterparts.

It would be funny to see a cleaning time comparison of a 12" cleaning path powerhead vs 9" or so you get with portables, especially once you factor in overlap and how how fast the head can be moved.

Your description of using a corded/bagged vacuum is funny though. Reminds me of this:

 

[Vacuum Facts]

Battery powered appliances almost universally will have more of a negative impact than their equal performance/class mains-powered counterparts.

You missed the point I made. It's not about battery use; it's about the low power consumption to achieve excellent cleaning results. The battery is neither here nor there. If recycled, it's unlikely the battery will have as great an impact as the materials in a larger machine, not least the big heavy motors which are polluting to make. This scales up substantially over a population and isn't trivial. Ignoring this is a copout.

It would be funny to see a cleaning time comparison of a 12" cleaning path powerhead vs 9" or so you get with portables, especially once you factor in overlap and how how fast the head can be moved.

Yes, but the performance achieved must be the same and the cost to achieve it factored in so sloppy copouts can't just jam a jet engine on the back. I'm aware of no reputable test.

Your description of using a corded/bagged vacuum is funny though. Reminds me of this:

Well, people might attempt to trivialise it, but the data, which can't be argued with, shows clearly that people are moving away from the hassle of corded machines. Soon parity will be achieved and thereafter cordless stick vacs (DC35 clones) will dominate the market. So, those trivialisations fall flat in contrast to the data.

 

[Hatsuwr]

You missed the point I made. It's not about battery use; it's about the low power consumption to achieve excellent cleaning results. The battery is neither here nor there. If recycled, it's unlikely the battery will have as great an impact as the materials in a larger machine, not least the big heavy motors which are polluting to make. This scales up substantially over a population and isn't trivial. Ignoring this is a copout.

Yes, but the performance achieved must be the same and the cost to achieve it factored in so sloppy copouts can't just jam a jet engine on the back. I'm aware of no reputable test.

Well, people might attempt to trivialise it, but the data, which can't be argued with, shows clearly that people are moving away from the hassle of corded machines. Soon parity will be achieved and thereafter cordless will dominate the market. So, those trivialisations fall flat in contrast to the data.

The additional impact from the battery comes from raw materials and manufacturing, charging losses, lifespan, and disposal.
Higher efficiency is of course a good thing, but you can't just look at something as simplistic as average wattage by itself and expect to get any meaningful insight.

I hope this isn't just devolving into another attempt at the mental gymnastics required to pretend that Dyson's current chosen form factor is the best solution for applications where it clearly isn't. That routine is getting very tired.

 

[Vacuum Facts]

The additional impact from the battery comes from raw materials and manufacturing, charging losses, lifespan, and disposal.

There's no evidence that when recycled, they have any more impact than large machines with big heavy motors and all the materials needed, including transport and disposal.

Higher efficiency is of course a good thing, but you can't just look at something as simplistic as average wattage by itself and expect to get any meaningful insight.

I don't. I look at the data showing performance per Watt under real-world conditions.

I hope this isn't just devolving into another attempt at the mental gymnastics required to pretend that Dyson's current chosen form factor is the best solution for applications where it clearly isn't. That routine is getting very tired.

It's not; It's a review of the data and evidence to support factual claims. Likewise, I hope your response isn't just devolving into another attempt to try to discredit and ignore when the data shows something that isn't what someone wants.

 

[Absolute Rainbow]

I think your overall list of factors could use a bit of expansion, but environmental impact is a bit silly to talk about in the context of using battery powered appliances in a residential setting. Batteries are used for portability, not for performance or environmental friendliness lol. Battery powered appliances almost universally will have more of a negative impact than their equal performance/class mains-powered counterparts.

It would be funny to see a cleaning time comparison of a 12" cleaning path powerhead vs 9" or so you get with portables, especially once you factor in overlap and how how fast the head can be moved.

Your description of using a corded/bagged vacuum is funny though. Reminds me of this:

You missed the point I made. It's not about battery use; it's about the low power consumption to achieve excellent cleaning results. The battery is neither here nor there. If recycled, it's unlikely the battery will have as great an impact as the materials in a larger machine, not least the big heavy motors which are polluting to make. This scales up substantially over a population and isn't trivial. Ignoring this is a copout.


Yes, but the performance achieved must be the same and the cost to achieve it factored in so sloppy copouts can't just jam a jet engine on the back. I'm aware of no reputable test.


Well, people might attempt to trivialise it, but the data, which can't be argued with, shows clearly that people are moving away from the hassle of corded machines. Soon parity will be achieved and thereafter cordless stick vacs (DC35 clones) will dominate the market. So, those trivialisations fall flat in contrast to the data.

The additional impact from the battery comes from raw materials and manufacturing, charging losses, lifespan, and disposal.
Higher efficiency is of course a good thing, but you can't just look at something as simplistic as average wattage by itself and expect to get any meaningful insight.

I hope this isn't just devolving into another attempt at the mental gymnastics required to pretend that Dyson's current chosen form factor is the best solution for applications where it clearly isn't. That routine is getting very tired.

There's no evidence that when recycled, they have any more impact than large machines with big heavy motors and all the materials needed, including transport and disposal.

I don't. I look at the data showing performance per Watt under real-world conditions.

It's not; It's a review of the data and evidence to support factual claims. Likewise, I hope your response isn't just devolving into another attempt to try to discredit and ignore when the data shows something that isn't what someone wants.

And the data shows it all. It and the physics have proved that the Dyson form factor is the way to go, whether it's be DC35-hand (right angle version) or the gun of V10-and-beyond (in line version), or even outright power-broom like PencilVac. You can fit a small yet efficient AND powerful motor and superior whole-machine (and currently cyclonic) sealed filtration all into a lightweight and long-lasting machine, especially provided genuinely sufficient R&D.

@Vacuum Facts but Dyson has already patented nearly it all, with only the oldest and most common of said patents involved having expired. There's no way around currently, though at the very least Dyson is a case of progressive capitalism... recently the mistake in the V16 and the generic-ness of the Spot+Scrub (Picea) appear to suggest the company's change for the worse...

 

[Vacuum Facts]

>_> and then you took it to a whole other level that killed this conversation.

 

[Absolute Rainbow]

>_> and then you took it to a whole other level that killed this conversation.

At least it's not my fault though... >_>

 

[cheesewonton]

Japanese household vacuums offer a good basis of comparison because the Japanese have a uniform method of measuring the cleaning power of vacuums sold in Japan. They call this "Suction Work Rate". The lab measures sealed suction at the attachment end of the vacuum, then they measure the volume of air flowing over a defined period of time. Suction and airflow are multiplied together and then multiplied by a factor. The factor is used because unlike the ISO technique for measuring air watts, which is the simultaneous reading of suction and airflow at a given moment in time with a given orifice size. The Japanese measure the volume of air over a period of time, which normalizes for the differences in airspeed across the orifice and for the effects of turbulence. The resulting value for Suction Work Rate is expressed in Watts.

Most corded power nozzle canister vacuums manufactured for the Japanese market by Japanese companies are rated somewhere between 300 and 680 Watts of Suction Work Rate with Hitachi being the company producing vacuums rated to 680 watts. The most powerful European canister vacuum sold in Japan, the Hungarian made run of Lux D820s were rated at 280 watts. The Hungarian models had a more powerful motor from Domel than the Swedish made versions which were rated at 240 watts. Japan market Tristars only manage 190 watts. Mieles sold in Japan are rated from 190 - 240 watts depending on the model. An Electrolux Ergo 3 is rated at 240 watts.

But when you look at their battery powered stick vacs the suction work rate is 250 watts or less. Dyson interestingly does not rate their products sold in Japan using the Japanese standard but rather posts ISO Air Watt number.

 

[Vacuum Facts]

That Japanese air Watts standard is also poor, since air Watts can technically be measured anywhere in the system, e.g. raw motor air Watts, or air Watts through a particular component/tool factoring in local air resistance, and it varies hugely. The international standard measures as a function of orifice size and thus indicates the maximum air power achievable. Air Watts are only relevant for above floor cleaning and indicate nothing about carpet cleaning potential for well understood reasons I cover in my lecture video. Carpet cleaning potential is driven by a) the cleaner head's pressure difference with atmosphere (suction) to drive high air speed through pile in whatever total air flow magnitude that results, and b) the cleaner head's propensity to maximise its utilisation by exposing trapped particles to the flow. How well this is achieved needs to be directly empirically measured. The cleaning performance can be compared against the total electrical power consumption that was required.

What I'm getting at above is the electrical power consumed to achieve very high levels of nominal carpet cleaning—so minimising energy consumption without affecting the very highest level of cleaning performance. I know you can get mains cleaner performance using just ~240 W of total electrical power (including brush bar and system losses), nominally. (This will transiently increase with increasing local dirt concentrations.) The machines you mention above I suspect there's no relative performance data for, and old machines that consume little power are usually terrible performers.

 

[cheesewonton]

Here is a typical Japanese stick vac rated by the JASO standard for Suction Work Rate. 150 watts.
https://www.japantrendshop.com/pana...AJeAFU0o0Li1_YMhE4bG_FFT1ODMHzBGbntyC2tuBlu8Y

 

[cheesewonton]

That Japanese air Watts standard is also poor, since air Watts can technically be measured anywhere in the system, e.g. raw motor air Watts, or air Watts through a particular component/tool factoring in local air resistance, and it varies hugely. The international standard measures as a function of orifice size and thus indicates the maximum air power achievable. Air Watts are only relevant for above floor cleaning and indicate nothing about carpet cleaning potential for well understood reasons I cover in my lecture video. Carpet cleaning potential is driven by a) the cleaner head's pressure difference with atmosphere (suction) to drive high air speed through pile in whatever total air flow magnitude that results, and b) the cleaner head's propensity to maximise its utilisation by exposing trapped particles to the flow. How well this is achieved needs to be directly empirically measured. The cleaning performance can be compared against the total electrical power consumption that was required.

What I'm getting at above is the electrical power consumed to achieve very high levels of nominal carpet cleaning—so minimising energy consumption without affecting the very highest level of cleaning performance. I know you can get mains cleaner performance using just ~240 W of total electrical power (including brush bar and system losses), nominally. (This will transiently increase with increasing local dirt concentrations.) The machines you mention above I suspect there's no relative performance data for, and old machines that consume little power are usually terrible performers.

Again, as usual you know nothing and didn't even bother to read what I wrote. The standard measures suction and airflow at the attachment end of the hose, wand or what have you. It is measuring air power at the cleaning surface.

 

[cheesewonton]

(This will transiently increase with increasing local dirt concentrations.) The machines you mention above I suspect there's no relative performance data for, and old machines that consume little power are usually terrible performers.

Kenmore actually posted those values for their old vacuums on a big sticker inside the lid. It lists suction in inches of water lift, airflow in CFM and air watts at the attachment end of the hose. Here is such a tag for a 1978 vintage Kenny. The sealed suction and airflow numbers are pretty close to what I measure using my own suction gauge and anemometer. 227 air watts at the hose end. That was what vacuums were doing 47 years ago.

https://i.ebayimg.com/images/g/nqQAAeSwVGRoofg1/s-l1600.webp

For the sake of comparison my Kenmore 600 is producing 90 cfm airflow at the hose end and mid 80s inches of water lift sealed suction, the hose end makes it hard to get a good steady reading. Now you are going to try to tell me a stick vac has more cleaning power, lol.

 

[Vacuum Facts]

Again, as usual you know nothing and didn't even bother to read what I wrote. The standard measures suction and airflow at the attachment end of the hose, wand or what have you. It is measuring air power at the cleaning surface.

I could retort in the same way. I know that. But that's only one use case. What about crevices, which are very different from the surface (resistance is lower)? This is what I meant by "air Watts can technically be measured anywhere in the system". And you claimed I "know nothing and didn't even bother to read what I wrote"...

Anyway, I'm also aware of the panasonic dupe of technology Dyson patented years before the release of this product and that was available publicly for all to copy from. There's no cleaning data to show such a machine can achieve mains equivalent performance. Again, this is what I meant by "The machines you mention above I suspect there's no relative performance data for, and old machines that consume little power are usually terrible performers."...and again, you claimed I "know nothing and didn't even bother to read what I wrote"

Kenmore actually posted those values for their old vacuums on a big sticker inside the lid. It lists suction in inches of water lift, airflow in CFM and air watts at the attachment end of the hose. Here is such a tag for a 1978 vintage Kenny. The sealed suction and airflow numbers are pretty close to what I measure using my own suction gauge and anemometer. 227 air watts at the hose end. That was what vacuums were doing 47 years ago.

https://i.ebayimg.com/images/g/nqQAAeSwVGRoofg1/s-l1600.webp

This is nice to see, but it's not relative cleaning performance data. Again, you claimed earlier I "know nothing and didn't even bother to read what I wrote".

 

[Vacuum Facts]

Here is a typical Japanese stick vac rated by the JASO standard for Suction Work Rate. 150 watts.
https://www.japantrendshop.com/pana...AJeAFU0o0Li1_YMhE4bG_FFT1ODMHzBGbntyC2tuBlu8Y

Incidentally, It's not clear what that "150 Watts of suction power" actually refers to either. Is it air Watts or Watts of electrical power? 150 W of electrical power consumption is extremely weak and will unlikely achieve effective cleaning. Typical vague advertising from sloppy manufacturers.