Water flow rate and drip surface tension

In summary, the drip size is highly dependent on the viscosity and surface tension of the fluid you are dripping.
  • #1
fdnovice7629
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0
TL;DR Summary
flow rate, water, drips, drop, surface tension
hello
i have a drip tube with water dripping and when i increase the flow rate or frequency of drips they get bigger/more massive.
i see the equation mass x gravity = 3.14(tube diameter)(surface tension)
my mass is changing but not gravity, 3.14 or tube diameter so surface tension must be related to flow rate but I can't find anything online on how to figure this out.
conversely I have a known flow rate and mass and want to determine tube diameter but unsure how to get it as it appears surface tension must be related to flow rate but I don't know how
 
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  • #2
Try search term liquid drop formation. Are you collecting data on drop size vs flow rate and tube diameter? Does the liquid attach to the tube ID or OD?
 
  • #3
fdnovice7629 said:
i have a drip tube with water dripping and when i increase the flow rate or frequency of drips they get bigger/more massive.
I have not seen that with IV administration. The drop size depends on the IV tubing size (macrodrip or microdrip), but not on the flow rate (in drops per minute). What size tubing are you using, and how are you controlling the flow?

https://www.mometrix.com/academy/calculations-of-drip-rates/

https://www.recoveringself.com/health/iv-drip-therapy-the-science-behind-the-fad

1603463967726.png
 
  • #4
drip weight absolutely depends on flow rate. I am using normal sized equipment
 
  • #5
So show us some data on drop size vs flow rate. It's easy enough to get accurate measurements: Flow per time divided by drops per time = volume per drop. Also a photo of your setup would be helpful.
 
  • #6
i have a known drop mass, known flow rate and need to calculate the diameter of the tube that it comes out of
 
  • #7
fdnovice7629 said:
i have a known drop mass, known flow rate and need to calculate the diameter of the tube that it comes out of
That doesn't seem like an accurate way to control a flow rate. Can you please just say exactly what your design requirements are?

And if you want to control/meter a flow, a peristaltic pump is a good option usually. We use them all the time in medical applications (like IV infusions)...

https://www.graylineinc.com/whitepapers/peristaltic-pump-tubing.html

1603495345358.png
 
  • #8
i have stated my design requirements.

drip size .05 gram
flow rate 150grams/hour
how big hole of drip tube?

the answer should take into account flow rate as is I increase the flow rate, with the diameter calculated above the drip size will go up.....
 
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  • #9
Sorry @fdnovice7629, the drip size is highly dependent on the viscosity and surface tension of the fluid you are dripping. Try getting a drop of alcohol thru your device, then try getting a drop of honey thru it.

The only way to get numbers for a fluid with unknown characteristics is to run a bunch of experiments. Even in hospitals, the Intravenous Drips are controlled by a constriction upstream of the drip chamber, effectively controlling the pressure to regulate the flow.

Cheers,
Tom
 
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  • #10
fdnovice7629 said:
i have stated my design requirements.

drip size .05 gram
flow rate 150grams/hour
how big hole of drip tube?

the answer should take into account flow rate as is I increase the flow rate, with the diameter calculated above the drip size will go up.....
Did you look into peristaltic pumps at all? 150cc/hr is certainly do-able with high accuracy...
 
  • #11
I am not here looking to purchase an item. I am here to determine the drip tube diameter required for my specs. It will be connected to an IV bag and then some other means of regulation will control the flow.
 

1. What is water flow rate and how is it measured?

Water flow rate refers to the volume of water that flows through a specific point in a given amount of time. It is typically measured in liters per second (L/s) or gallons per minute (GPM). This measurement can be obtained using a flow meter or by calculating the change in volume over time.

2. How does surface tension affect the flow rate of water?

Surface tension is the force that holds the molecules of a liquid together at the surface. This force can impact the flow rate of water by creating resistance, which can slow down the flow. However, surface tension can also allow water to flow smoothly over certain surfaces, such as when water forms a droplet on a leaf.

3. What factors can influence the surface tension of water?

The surface tension of water can be influenced by temperature, impurities, and the presence of other substances. For example, adding soap to water can decrease surface tension, while increasing the temperature can increase it. Additionally, the shape and size of the container or surface can also affect surface tension.

4. How does water flow rate impact the effectiveness of irrigation systems?

The flow rate of water is a crucial factor in the effectiveness of irrigation systems. If the flow rate is too low, plants may not receive enough water, leading to poor growth or even death. On the other hand, if the flow rate is too high, it can cause erosion and damage to plants. Finding the optimal flow rate is essential for efficient irrigation.

5. Can the flow rate of water be controlled?

Yes, the flow rate of water can be controlled through various methods. For example, flow restrictors or valves can be used to limit the amount of water flowing through a system. Additionally, adjusting the pressure of the water source can also impact the flow rate. It is important to carefully monitor and control the flow rate to ensure efficient use of water resources.

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