Artic Master RMS- 5

[ClydeMule]

Has anyone seen or heard about this thing called an Artic master RMS. It used to be called a Talon RMS.

The website

http://www.articmaster.com

makes some pretty impressive claims about what it can do. It is a vessel installed in the same place you would put a receiever in an air cooled system. It makes some kind of vortex, which they claim:


*Reduces Head pressure
*Reduces Energy Costs
*A whole bunch of other great things.

While I am skeptical of the claims, I am not going to debunk the thing immediatley, because they have some testimonials and an Plant Engineering award (albeit unverified). My guess is that the claims are true, kind of, but how they explain how it works is wrong. I equate it with a liquid/suction heat exchanger. People think these magically give you more capacity. They do only if you have flash gas in the liquid line ahead of the TEV, which is common.

The only thing close to a technical explanation is a line which talks about how the vortex creates turblent refrigeration flow which helps cool the oil on the surface of the vessel. THis may be true, but how does that save you 20%?

I also have a cost savings spreadsheet from them which is amateur at best.

Thanks,

Clyde

 

[ChasBean1]

This is an excellent topic and must not die until I find the answer!! Everything the net has to offer on this is heavy in marketing and poor in engineering explanation.

Some of the client testimonials are like: "I can turn my thermostat back up now!" and "This room used to be too hot, now it's 8° cooler!"

Works fine lasts a long time won't rust won't bust buy now four easy payments of 29.99 doesn't cut it. They tell a little - lowering the laminar boundary layer by using a vortex, but I tend to think that going through a throttling process (TXV) tends to create turbulence also!! I hope to hear from someone with experience or that can add something based on theory.

 

[ProfSporlan]

I've known about this device by its former name, Talon RMS, for a number of years. In fact, I would enjoy discussing the pros and cons of such devices which portend to improve system efficiency and performance from a thermodynamic or operational standpoint with others. One problem with eliminating laminar refrigerant flow in a liquid line is that a properly sized liquid line will not have laminar flow to begin with. For example, a 10 ton R-22 a/c system employing a 5/8" OD liquid line, the refrigerant flow will have a Reynolds number of about 11,000. Laminar flow normally requires a Reynold number of 2000 or less, which would require a 3-1/8" OD liquid line in this case.

 

[ClydeMule]

I think what they are saying is that they create turbulent flow in the receiver, and increase the heat transfer coefficient between the liquid refrigerant and the air outside the receiver through the receiver wall. So if heat is removed from the liquid while in the receive, we have increased the subcooling of the liquid.

Big deal. If you look at the PH chart taking subcooling the liquid 25 F only gains about 10-12 % (due to change in enthalpy). However, most AC systems are going to have a liquid temp of 100 or so, so unless it is cold outside how does the change in heat transfer coefficient do anything. This is also counter to their claim that the hotter it gets the better it works.

They make another interesting claim about how it reduces the system pressure. I could put a huge chunk of wood in a piece of pipe and VOILA!, the pressure is lower, downstream of the blockage. A true but meaningless statement.

They also say in another section that it lowers suctio pressure as well. No wonder the amp draw was lower.

Again, if this thing actually works, great. But why? They don't even seem to know. That's probably why only a factory authorized guy can install one. I should call them tomorrow and see if they will sell me one as an OEM.


ADIOS

clyde

 

[ProfSporlan]

I see where I've erred in my Reynold's number calculation by a factor of 10. To set the record straight:

R = v * D * rho / (u * gc)

where:
R = Reynold's number
v = velocity, ft/sec
D = ID of tube, ft
rho = density, lbm/ft3
u = absolute viscosity, lbf-sec/ft2
gc = gravitational conversion factor, 32.174 lbm-ft/(lbf-sec2)

For our 10 ton R-22 system:

NRE 40/100 = 68.8 Btu/lbm
Refrigerant flow rate = 200 lbm/min-ton * 10 tons / 68.8 Btu/lb = 29.1 lb/min

A 5/8" OD copper tube will have an ID of about 0.545", or D = 0.0454 ft

rho = 71.1 lbm/ft3 at 100°F saturated liquid

refrigerant velocity thru the tube = 29.1 / (rho * pi * D^2 / 4 * 60) = 4.21 ft/sec

u = 3.878e-6 lbf-sec/ft2 at 100°F saturated liquid

Therefore:

R = 4.21 * 0.0454 * 71.1 / (3.878e-6 * 32.174) = 108,917

To obtain a Reynold's number of 2000, v * D must equal 0.00351 ft2/sec.

Therefore:

0.00351 = 29.1 / (rho * pi * D^2 / 4 * 60) * D
0.00351 = 0.008685 / D

D = 2.47 ft

 

[quark]

I do agree with all you guys (I presume I am not thought blind too) Is there any chance that because of turbulence, pressure drops to cause flashing before expansion valve? Or if the pressure drop not significant where does turbulence occur?

Is there no trade off between subcooling and work input?

But I would like to listen the manufacturer's comments via Clyde if he ever discusses with them.

 

[ChasBean1]

Sporlan - good to see you chime in. Assuming your Re calc is accurate, that is a hit against the manufacturer's claims. You mentioned familiarity with the Talon - what are some pros and cons here? With these energy savings claims brought about essentially by the fluid doing additional work (and no additional work done on the fluid), what is the energy source? Paul appears to be the compressor, but who is Peter?

 

[ClydeMule]

I contacted the MFG about installing one of these on one of my machines as a test. (I build air and water cooled process chillers). The request was declined, based past history of OEM's not "doing it right" and therefore saying the articmaster didn't work.

I got a number of names dropped during the conversation, of rather large companies that have them installed. Of course, I have not verified them.

A couple of statements regarding installation:
*There must be nothing in between the articmaster and the TEV. THe idea is that this thing creates a vortex not only within itself, but through the whole liquid line. No LLSV, sight glass, drier, etc. These would break up the vortex created by the Articmaster.

*It must be installed above the condenser. Not above the liquid drain, but above the highest coil. THe idea is to start the "gravity flow." I guess that is why they call it a gravity pump. Whatever that is. If this is a split system with the evap coil above the condensing unit I don't see how that makes a difference.

*It imposes no pressure drop. OK.

I was able to summarize and have the mfg confirm:

THe artcicmaster creates a turbulent flow in the liquid line which increased the heat transfer from the liquid to the outside air, which would increase subcooling.

That is assuming, that the Prof is wrong and there is not turbulent flow in the liquid line. I think I agree with the Prof.

However, even if they are right, it does change the liquid from laminar to turbulent flow (and the Prof is wrong) creating more heat transfer and increasing the subcooling I don't think that it can create that much savings.

According to Copeland Application Engineering bulletin (or any p-h) chart for every 10 F change in subcooling you get 5.6% capacity increase @ 130F condensing and a 3.9% increase @ 90F condensing. This is why they say that it works better when it is hotter outside. This is also why they say that they have more savings with a air cooled as opposed to a water cooled system.

So if we take an average AC system operating @ 130 F condensing in 100F ambient, the lowest theoretical temperature of the liquid due to subcooling from the ambient air would be 100F, or 30 F of subcooling. So 3 times 5.6 is 16.8 % increase in capacity. No wonder it was so cold in the house!

This of course would be a theoretical maximum. For natural convection of a 1/2" diameter copper pipe in still air, the limiting heat transfer coefficint would be on the outside of the tube not the inside. Making a change from laminar to turbulent flow not very significant. The best gain would come from running the liquid line through additional coils with incoming ambient air being drawn across by the condenser fan.

Still, there could be real savings in a limited number of situations. If the savings are small, they are still savings. Especially if the thing is not that expensive.

Anyway, here is the info I have received. I would love to hear some input on these new facts.

ProfSporlan: Thanks for you calculations. I believe your numbers are correct.


Clyde

 

[ProfSporlan]

You mentioned familiarity with the Talon - what are some pros and cons here?

Invariably, I hear about all of the energy saving devices being promoted to the refrigeration trade. Obviously, some have more merit than others. Manufacturers of refrigeration flow controls generally don't get too excited about these devices one way or the other unless they affect the operation of their products. Most manufacturers of refrigeration systems are more than capable of evaluating these devices, and advising their customers as to their value.

Evaluating claims of energy savings based on thermodynamic principles, however, is a useful exercise for anyone involved with the design and/or servicing of refrigeration systems. If a device claims to save say, 25 percent in energy costs, then the savings must be accounted somewhere. The First Law of thermodynamics requires it. So armed with an understanding of P-H diagrams, psychrometrics, heat transfer, fluid flow, and evaporator/condenser/compressor performance, one should be able to evaluate such claims, at least on a theoretical basis. There is no "black magic" in refrigeration.

Clyde asks a pertinent question: what if this device creates additional subcooling on a particular system? And what additional energy savings does that produce?

ProfSporlan: Thanks for you calculations. I believe your numbers are correct.

I got it right the second time around...

 

[ProfSporlan]

Perhaps on a related note, you might find it interesting that vortex flow has been used for industrial spot cooling. A device variously known as the Hilsch vortex tube, or the Ranque-Hilsch vortex tube, uses compressed air as a power source. An interesting article on this subject can be found at:

http://www.visi.com/~darus/hilsch/

The principle, however, doesn't work with liquid flow.

 

[edbvp]

Clyde,

What was your final outcome with Artic Master? They recently invited me to SBC in California to see their results and I am impressed.

Please let me know what you discerned.

Best regards

Ed

 

[ClydeMule]

edbvp,

I never wound up using it. They don't want to sell it to me and have me install it so it wouldn't not be worth the few percent I MIGHT get out of it.

I am still skeptical of the device mostly because all of their marketing is not very scientific. In addition, most of it is lame. "It was so cold in the house." Temperature is temperature, whether or not you used a articmaster or not. If the house suddenly got to cold after it was installed it means the guy who put it in broke the tstat.

I would like to hear you opinion of the device since you saw it yourself.

Adios.

Clyde

 

[rhettgraves]

edbvp et.al.,

I've been doing some energy conservation work for a company that has been approached by ArticMaster. The way they make money is by getting you to agree to write them a check. Before the installation, you have to sign on the dotted line guaranteeing that their "energy savings" are correct. Regardless of what the real savings are, you've agreed that they are x-percent and you cut them the check before the can is ever put on the machine.

Looking at their "energy savings" calculations, check out the entering air enthalpies. You'll notice that the retrofit entering air enthalpy is MUCH lower than the original, i.e. there's not as much load on the machine!! Of course the compressor power is reduced in this case.

If you want to make them go away, just ask them for a temperature-entropy diagram that explains the operation of their device. They'll go away for a few months. Continue to ask the engineering questions and they'll eventually give up. Just my 2 cents.

Rhett Graves

 

[Montytrader]

I have just come from site where I was invited by the property owner to report on a malfunctioning unit,whilist I was there I saw the completion of a Articmaster installation.

I saw two Carrier split units each has two Articmasters installed, as I was conducting some maintenance I asked to see any log books. What I saw was quite fascinating.

The Amps draw was reduced by 8.5%to 11% and the delta Temp improved by 7 degree F (average),I asked some of the on site people if they were impressed. "YES",so was I.

I had not seen these before and decided to do some research,thats why I am here to lear if others have witnessed a installation and can explain why this little "blue beauty" works

 

[GuruRu]

I work for an energy services company and we tested the artic master extensively, many years back. The manufacturer does hype it a little too much, but they work quite well. Installation is not as easy as the manufacturer will lead you to believe, but electrical savings has averaged 20% - 30% for the units we've overseen installation for.

For maximum energy savings, we now standardly recommend premium efficiency motors, VFDs, and artic masters.

 

[jpthiede]

I have been an ArticMaster rep for a year and a half now. I am also frustrated with the lack of scientific "proof" by the manufacturer. I have personally seen many installations and results. My company has trained several HVAC/R companies on installation (which has MANY interesting problems). I hate telling people that you have to see to believe.

I have run into an application that does not show the guaranteed 20% savings. I am very frustrated that I am not getting adequate technical help from the manufacturer. Pretty much, I am getting guesses as to what is wrong, which verifies an earlier post about troubleshooting problems.

I would be more than willing to talk with anyone that wants to try and figure out the "nuts and bolts" of this device. I also would add, that unless you have been properly trained in the installation - DO NOT DO IT! This is why they will not just hand one off to you and trust that it will be done right. It totally changes the way that you charge and evaluate a system. This in and of itself is a difficulty. ie. Do away with your subcooling and superheat measurements, they no longer reflect the charge in the system.

I would also be open to sending a pdf copy of the installation manual that comes with the ArticMaster unit for evaluation if anyone is interested.

-J. Thiede
ArticMaster Rep

 

[tommytn]

yes, please, I'd like a pdf copy. ttabolt@yahoo.com
thanks.

 

[jpthiede]

I just sent a copy to you tommytn. I have been doing quite a lot of research lately and would be very interested in pursuing this thread further.

I also have lab tests, before-after field readings, etc that I would be happy to share and discuss. I am looking forward to answering some of your questions if I am able.

With the knowledge that I have at this point, the ArticMaster does several things:

1-By creating a vortex, it pulls the cooler refrigerant to the center, thereby forcing the warmer refrigerant to the outside of the vessel to continue to loose heat to the vessel.

2-This vortex allows a colder coil temperature, even sometimes below 32 deg F by allowing some flash gas through the center of the vortex and thereby "defrosting" the coil before the system itself can respond. The added vapor reduces the efficiency of the evap coil but is offset by the other benefits of allowing a colder coil. (by about 5-10 deg F on average)

3-The vessel in and of itself, as with any receiver, adds maybe 2-4% increase in system performance just because of the properties of a receiver. Some sub-cooling and increased refrigerant capacity, effectively increasing the condensor capacity by up to 20%.

4-It creates a "mixing" of the refrigerant which allows a more uniform heat transfer and helps (along with added velocity) to sweep deposited oil, that acts as an insulator, off of the refrigerant line walls. This also reduces the load on the compressor as less work is required to move the refrigerant.

You may also be interested in reading the patent which I would also be more than happy to send to you in pdf form.

-J. Thiede
ArticMaster Rep

 

[PacificSteve]

The local utility did energy measuring before and after intallation of an ArticMaster and found no change in energy usage.

I wasn't involved, but sure like the intuitive nature of real kWH measurements.

PS

 

[GuruRu]

Thats interesting, because I've personally metered KWH for about 25 units and always seen considerable savings. I hope they returned it for their money back.