Juice flowrate equation help

[Vapinginjapan]

Mods, if this is in the wrong forum, please move it.

Alright, one of the holygrails of e-cigs is the fabled automatic pump.

Some recent research that i've been doing has convinced me that this IS feasable, and within the price range of about half a mod, as a module that would screw onto the mod and potentially allow a 10ML-ish juicetank to be fitted onto the mod.

Now, while I would like to keep this research underwraps for the moment so as not to disapoint people, I need to solve a specific equation. For this, I need your brain power.

My plan, for this automatic pump, to make it as compatible as possible with the equipment out there, is for it to sit between the atty and the battery, feed off the power the mod is providing (so switching on the atty switches on the pump) and have it deliver juice only when the atty is running.

For this to work, I need to figure out the PRECISE flow rate needed to make sure the atty is neither starved nor flooded.

So I, in essence, need to figure out how many micro liters per minute of running time for the atty is necessary to achieve this.

My ballpark figure is about 100ul (0.1ml)/min to keep the atty fed on an 801 at 3.7v (my sole experience as far as e-cigs go, of the non carto variety)

Can anyone help me refine this figure with your personal experience? Drippers, specifically. If we're assuming a standard drag is 5 seconds, and a drop is 1/25 of a ML, how many drags can you get off a drop of liquid before vapor production weakens?

I would appreciate figures for all varieties, but the main figures I need are

801 3.7v
801 6v
501 3.7v
501 6v

I would just like to end this on the note that I am working with the interests of the community in mind, and if I succeed in this venture, I will post the full specifications, and parts lists, to the entire community as a sacrifice on the altar of the better vaping experience, free for all of the mod makers to exploit.

While I would love to profit off this invention, I feel it would be inappropriate.

So please, help me! Lend me your collective knowledge.

 

[l3oertjie]

How about using peristaltic pump action as a function of lip pressure on the cart? That could be a mechanical devise not requiring any additional (and valuable) battery power...

 

[Vapinginjapan]

So, what you're saying is, engineer the peristaltic pump to be powered by a turbine in the venturi?

I think A. I'm not sure if suction would generate enough power to move the amount of liquid necessary, and B. This is completely beyond my engineering capabilities. It's simple to rig up a cheap peristaltic pump up to the battery and match flowrates, it's much more difficult to engineer a mechanical system to do the same job.

Plus, it'd probably dramatically increase drag resistance.

The pump I am using is a peristaltic, but I doubt sucking could ever generate the torque necessary to spin it, and it'd be a ..... to design.

 

[IdolLurker]

Mods, if this is in the wrong forum, please move it.

My plan, for this automatic pump, to make it as compatible as possible with the equipment out there, is for it to sit between the atty and the battery, feed off the power the mod is providing (so switching on the atty switches on the pump) and have it deliver juice only when the atty is running.

For this to work, I need to figure out the PRECISE flow rate needed to make sure the atty is neither starved nor flooded.

So I, in essence, need to figure out how many micro liters per minute of running time for the atty is necessary to achieve this.

My ballpark figure is about 100ul (0.1ml)/min to keep the atty fed on an 801 at 3.7v (my sole experience as far as e-cigs go, of the non carto variety)

Can anyone help me refine this figure with your personal experience? Drippers, specifically. If we're assuming a standard drag is 5 seconds, and a drop is 1/25 of a ML, how many drags can you get off a drop of liquid before vapor production weakens?

I would appreciate figures for all varieties, but the main figures I need are

801 3.7v
801 6v
501 3.7v
501 6v


So please, help me! Lend me your collective knowledge.

I think you are starting to go in a very logical approach - at least for me since I am a scientist and evaluate data for a living. But at the start you must make sure that you are taking into account all the variables. What you have listed is a start but that is not all of the controlling variables. I would suggest having a continuous range for the user to adjust the flow of the liquid.

I am not an expert at this vaping and have struggled with getting the equipment working just right...and offer these issues to be considered.

Drip or cartomizer
Manual or Automatic battery
Equipment features - basic PV (adjustable draw etc.)
Atomizer
Type of Tip and Cart Mods - e.g., blue foam, tea bag
Voltage (you mentioned this)
Battery - drop off with use or manufactured cut off
Ejuice - PG, VG or mixture of both
Ejuice - thinner used (DI water or alcohol)
Range in Viscosity of Ejuice (very important for DIYers)
Personal Methods of Vaping by User (draws/min; intensity of draw)

Here is a post from other thread that I found helpful for others that may be giving you some data. Easy way to get a relative viscosity that you can use in product development.

Originally Posted by Rocketman
Ralph,
I have a method I use that does not produce a real viscosity value, just a relative value that is repeatable. I use a 10ml ink cartridge hypo with a rather LARGE blunt needle. I run VG through it and the drop time is about 12 min/ml. I have some PG that may have absorbed some atmospheric water vapor that drops at about 1.5 minutes per ml. A few different PG based Chinese Juices that also drop at about 1.5 minutes per ml.

Cutting the PG and VG with distilled water at about 10%, 25%, 50% gives an exponential curve of decreasing drop times. Pure water is about 1.5 Seconds per ml.

I vape 50/50 juice (PG/VG) and cut it with 100 proof Vodka (water and ethanol, right?) to get between 1 minute and 1.5 minutes per ml drop time. Without dilution the 50/50 (if PG Nic juice I cut with VG, and if VG Nic juice cut with PG) gives about 3 minutes per ml. Let the needle run for about 1ml then start timing. Should be laminar pipe flow by that time. Measure over a few ml and column pressure drop shouldn't matter between liquid as most are pretty close to the same density anyway. My 50/50 was too thick to wick, and my dilution wasn't repeatable. Now it is. And you drop from the syringe into a bottle so it ain't wasted.

The Rocket

Hopefully you can develop something that all of use can use.

 

[l3oertjie]

I'm thinking as follows:

Have a reservoir with a soft - almost balloon like side on one end that could be compressed with your lips. A tube with a non-return valve to the atomizer heater element and an air-vent to allow air to be drawn into the reservoir. If you press your lips against the balloon, pressure will increase in the reservoir and push the liquid to your atomizer. The amount of liquid will depend on the pressure exerted. Obviously the air intake will also have to have a non-return valve.

 

[Vapinginjapan]

That's definatley a fascinating idea.

Unfortunatley it'd make it extremley difficult to get it to work to all devices. For instance, some people on 6v need tons of liquid out of their atty, and tend to blow through it quite quickly. They would need a large sized balloon. 3.7v users would need a smaller one. Within 3.7v, I imagine different 'juice used per drag' would be evident among the models. It seems like it would be a royal headache.

Granted, a peristaltic pump would have similar limitations, and your approach is much lower tech. Hmm.. this warrants some thought. Thanks!

 

[l3oertjie]

You're welcome.