Richard.

I simply asked you how you arrived at your claim. I have done tests and I am certain of my findings. I have used flow sensors that are accurate and perfectly calibrated and I even ran the system into a cup to test to make sure.

This is not the best video quality for some reason youtube has messed up the resolution pretty bad.

I would also like to point out that anyone with our pump can test this out for themselves as well.

http://www.youtube.com/watch?v=bfYt-2jmK40

 

I suppose it is possible. Unless the nozzle has something loose inside during the pressure ramp, it should stay true to a M5 characteristic flow. I cannot imagine this can happen to a M5 nozzle.

 

David,

Just watched the video, it is good just enough to see the grauduation on the computer screen. The 250 pump bounds around the 700cc mark?

Can you confirm this?

 

there is nothing loose in it. There may be some nozzles on the market that max out at a specific pressure and while technically all nozzles must have a threshold where it will no longer flow more with higher pressure, our nozzles will go past 250 psi.

If a nozzle had a max pressure range of lets say 150 psi, I can see your point.

The video will clearly show the difference between the 150 psi and 250 psi pump using the same input signal and controller.

 

yes the 250 psi maxes around 711 CC. Both have identical scales setup. 1000 cc is the ending mark (which is never realized on this size nozzle). I will when I have a chance make a better video, maybe I will enlarge the gauges so its easier to read.


There is no checkvalve in line and dutycycle starts at 5% ends at 100.

 

When you prepare your video for public viewing, showcasing your new 250psi pump (very nice by the way).

You showed your software simulated gauge on your laptop, receiving signal from your flow sensor.

Here are list of items included in your test:

1. Flow sensor (calibrated by you, believed to be accurate)
2. Software interpretation of the train of pulses to drive your simulated gauge.
3. A M5 nozzle (certified, and no loose parts internally)
4. I assumed you have also measured the sprayed water on an weighing scale or graduated measuring glass.
5. Published you claim

It is the test procedure your performed? I am sorry for the questions but I need to be clear, because it is not physically possible to have this amount of flow from a M5 nozzle at 250psi.

 

Here is another way for me to put it.

I have attached an image from a popular misting nozzle manufacturer. Its a company called HAGO. These are not our nozzles, however it makes a good example.

It shows the difference in flow from 40 psi to 500.

based on this, you would have to agree if the pump is capable of flowing from 40 psi to 250, you would have a far greater than 2 X flow rate.

Am I missing something that is obvious?

 

yes, as mentioned every single one of those points in my post. I did measure it in the flow.

Look at the chart I posted from HAGO (A different nozzle manufacturer) It shows a M5 to be 3.16 GPH @ 40 PSI 5 GPH @ 100 and 11.1 GPH @ 500.


seems to be somewhat in line with what I have seen. However they are a different brand, its just to show a point. My point is that it has far greater than 2 times dynamic range ( based on my findings).

 

Good, we are on the same page or on the same M5.

My claim was from 60-240 psi "4x the pressure = 2x the flow"

Need to go out of an hour, I will be back.

 

David of Coolingmist,

Can we discuss the range of an M5 between 60-240psi - this is the range I claimed "x2" dynamic range. You picked me up on this and claimed I was wrong, based your set up.

Here is a calaculated chart and see the flow at various pressure points, from 50psi up. My claim was from 60psi up.

M5 at 60psi=244.32cc/min
M5 at 240psi= 488.64cc/min

The flow increase is 488.64/244.32 = 2.0000000000. Unless my calculation is wrong by a factor of ~45% or your test is out by the same amount, one of us is making fault claims.




If you have physically measured your spray quantity after one minute, check your measuring device again.



Your claim of 710cc/min at 250psi on your new pump (by-pass set at 250psi) is not possible.

 

Richard of Aquamist.

I have tested, I have measured. I did the test and I am confident. If you would like I would be glad to hook the pressure gauge to the line, give 12Volts to the pump and put into a cup for 30 seconds.

MLs will be on the cup. Would that be convincing? I can even get the old school nozzle with the M5 listed on it.

Let me know if that would be enough to please you sir.

David

 

holy **** its like a really polite war...weres the damn popcorn?

 

I don't really know what to say, how can your products defy the law of physics time and time again.

Here is a better plot of show the pressure required to flow 700cc/min pass a M5 nozzle:




My question to you is: How you can you flow 700cc/min of water pass a M5 nozzle with pump with 250psi by-pass valve installed.

Please tell me it isn't true...

 

Richard,

When I get back next week I am going to do more testing as I have time. I have to say a few things. First, I did not open the nozzle up to look inside it. I did not test a second nozzle to compare. lastly, the pressure gauge ends at 200 PSI. I turned the **** on the pump down, so it is possible the pump pressure could have been more than 250, maybe 280 or 300. This is something I jus thought of. I have a 300 PSI glycern filled gauge that I will use instead.

So there are a few variables at play. I will also see if I can dig up a standard "HAGO" M5 and compare to our "M5" and see if there are differences.

I will update as I have time.

EDIT: You dont have to be a smart *** saying that our products "Defy the laws of physics".

 

Richard,


The tests I did on that nozzle were correct. But as I said I did not open the nozzle up. I will actually inspect inside it.
I want to back it up on another one of my M5s and then compare to a standard M5 from another nozzle manufacturer.

All I want to do is see why there is such a discrepancy between what you say and what my tests show.



David

 

 

Richard,


I do not use Hago nozzles, but it will be the best test to compare our M5 to Hagos as I have a few Hagos laying round (I think).

 

i sure am scratching my head here....

i always thought flow was the product of the square root of the change in pressure?

i also implore both of you fine people (no sarcasm) to simply reach whatever conclusion is correct. no animals were harmed in this thread and you two have alot more in common than not.

there are also a growing number of customers out there in the FD community since we are generating 1.6 hp per cubic inch stock and who is stock?

way too much Combustion Chamber Pressure not to be running an Aquamist or Coolingmist system. (alphabetical)

to be continued with grace.

hc

 

awesome!

 

Flow through a fixed orifice is proportional to the square root of pressure
This is true and you can base your flow prediction on this with confidence.

As an engineer, I am very passionate about accuracies. I have been in this business for a long time, I have seen so many claims and hypes. I normally turn a blind eye to it, just accept that you cannot change the world over-night. All I can do is pass on what I know to the best of my knowledge, accumulated over the years, hope people will make better judgement for themselves before buying a product.

Back to the flow vs pressure...

A (positive) displacement pump such as shurflo will generate pressure proportional RPM, provided the pump can use and draw unlimited power.

As seen from the above curves a linear pressure increase will not produce a linear flow, otherwise the plot will be a straight line. This is one area I did not mention on my write-up above. A PPS system's flow is not predictable by ramping up the motor speed. I think I have said enough.

You have followed all the right paths on building your system up, I cannot find any fault there at all. Sometime people don't give you enough credit for your hardwork you put in so far... I believe it is slowly working through, I just wish it is quicker.

 

flow is proportional to the square root of the pressure change AT a given orfice size.

for example using the chart in post 42:

M5.

40 psi flow is 3.16
200 psi flow is 7.07

200/40 = 5
square root of 5 is 2.236
2.236 * 3.16 = 7.0659 case closed.


i too do not understand how David's flow test can be correct as it ignores the pressure flow equation.

David's flow numbers appear to show a linear relationship. to get around 700 CC/Min out of an M5 you would need around 500 PSI using the generally accepted formula and the flow data from Hago.

let's just figure this out without getting all riled up.

hc

 

Howard,


My test was accurate under the conditions that I stated. I can say this, the nozzle I used performed in that manner, exactly as stated.

As pointed out, I did not open the nozzle up to look inside and I did not verify against another of the same nozzle. I realize I should have done this. We have found nozzles that have slight differences. Its not often but it happens.

also, this "M5" nozzle is not the same brand as the Hago. While "M" should be a standard, it does not mean its accurate. For example the M14 of a nozzle from one company flows identical to a M10 of HAGO.

I am going to compare the M5 of a HAGO to the one we used and see what the difference is.


I think everyone needs to just chill.

 

It is getting silly, can you tell me whose M14 nozzle flows the same as the Hago M10 nozzle? You kept using Hago brand as reference, why not use their nozzles and call it a day.

45 percent deviation is just not on from any manufacturer.

If you go to a shop to buy a 12" rule and go to another one and they try selling you a longer 12" ruler. The second shop keeper will say to the guy " hey buddy, this ruler has more bang for the buck".

 

as long as the nozzle is constant the increase in flow would follow the square root rule. i am not disputing an absolute flow number, rather the relationship between two flow rates at two pressure levels.

hc

 

Past all the techy stuff... best thread Ive read in awhile.