# Tag Info

21

While pumping powders as a mix with swiftly moving gas is viable, one of frequently used alternatives for both powders and granular materials is Archimedes' Screw. Essentially, a helix in a diagonal pipe making the material "pour/roll" upwards the curve, allowing lifting it a long distance. This solution is frequently used in farming equipment for ...

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You may also look into pneumatic conveying. It involves fluidization of the particles. This simply uses pressure differential to move any bulk material. It's used a lot in industrial applications. You can read a summary of those systems, here.

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There is a key difference between liquids and powders: Liquids have internal cohesion and can be sucked, but with a powder, you need a carrying medium. The internal friction in a powder will usually be far higher than in a liquid. In practice, this means that to pump a powder, you inject air or another gas as fluidizing agent. The pumped or blown air ...

5

I'm going to cheat by referencing the patent. ;) Automatic Bar Controls owns the Wunderbar site and has a patent on the product. The patent is US008925769. The actual detail drawings don't seem to be available there though, so you have to get it straight from the US Patent Office listing. The name of the patent is: Wireless spout and system for dispensing. ...

4

Nozzle design can be fairly complex, but basically the nozzle speeds up the velocity of the fluid to the point where inertial forces exceed surface tension forces, and the fluid breaks up into drops. The Weber number, $We = \frac{\rho u^2 l}{\sigma}$ is a convenient parameter to do a basic analysis on a nozzle flow. In this equation, $\rho$ is the fluid ...

4

Consider an alternative to the current placement of the cans. The image above from the Pinterest web site, UN Food and Agricultural Organization shows a wheel in which the cans (bamboo tubes) dump the water to the side into a trough. I'm not suggesting that you duplicate this design, but if you turn your cans slightly to the side, you can have a chute or ...

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It is an aerator for the pond. They use them for oxygenating the water and for circulation. Link to the Pentair model in picture

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Theoretically, yes, but practically ,no. Regular 1" PVC will have very little flow restriction compared to the strainer and flex suction tube. Suction restrictions are always more important. And to be certain of no affect of discharge pipe I used about 30 ft of 2" PVC for my pond system . It cost a couple dollars more but nothing in the total cost. ...

3

It is possible to modulate the drive of some types of solenoid fluid valves to ultimately regulate the pressure of the fluid at their output port. I have designed a product that does excatly that. However, you can't easily use any valve. You want a valve that is intended for part-way operation between full on and full off. There are such solenoid valves, ...

3

I am assuming that your question is "how to increase the flow rate" and that your pump is a centrifugal pump. For centrifugal pumps, the flow rate out of the pump is dependent on the pressure at the exit of the pump. If the pressure is high, the flow rate will be lower. If the pressure is low, the flow rate will be higher. That dependency is typically ...

3

the fibers forming the pen filler are less densely packed than the fibers forming the nib, which extends into the filler a significant distance. This creates a capillarity gradient wherein the nib has a greater affinity for the ink than the filler does, and tends to saturate itself at the expense of the filler. The capillarity gradient guarantees that 1) ...

3

In food process you can "pump" powder with vacuum, sugar works very well, and some other products need sometimes some technical adjustment (pression or open/close cycles valves) . But water in the pipes is ban and last point it's only for small quantities and short distance 20meters max i think.

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You can pump both liquids and powders into a "mold" using injection molding. It works more easily with liquids, but it can also be done with small particles such as powders that are injected into heated molds with sufficient force.

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In short, capillary action. The fibrous content of the tube is literally designed to be saturated by the nib dries out creating an imbalance in fluid pressure leading to ink flow towards that direction.

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I'm an electrical engineer so this problem looks to me like an RC (resistor-capacitor) discharge. In the case of a resistor discharging a capacitor the time constant is given by τ = RC. In your case C represents the tank capacity and R is your R1, the resistance to flow. Figure 1. The top curve shows the capacitor voltage which is analogous to liquid level ...

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You need to measure from the top of mercury column, in tubes that are wide enough to allow a flat area of mercury on top and ignore the lower level along the perimeter where mercury is repelled by glass. This page has enough detailed instruction on calibration of barometers. Green river U link.

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If the flow rate is low for the gas then a ball that floats on the liquid will work - similar to how most wet vacs stop liquid getting into the motor...

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There are many, many different commercially-available designs of fluid connectors that shut off automatically when disconnected and open up when connected. They are available in plastic and metal, permanent and disposable, in all sorts of sizes. Try a search on "make-and-break fluid connectors".

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The way I understand it, is that (at least in laminar flow) viscosity is proportional to the "stickiness" between the layers of the fluid. I.e. higher viscosity, means that if a layer starts to move, then it will sweep along more forcefully the adjacent layers. Additionally in the example of the Couette flow, the velocity of the top layer ...

1

If the flow rate is 5ml/min, and you want to know how long a tube it will take 1 min to pass through, you’re effectively asking how long a tube contains 5ml. Volume of a cylinder is $\pi*r^2*h$. 5ml = 5000mm^3. Pi*r^2 = Pi*2mm^2 = 4pi mm^2 Your length therefore is 5000/4pi or around 400mm.

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If you like living, do not attempt to build your own high-pressure LN2 tank if you have never designed commercial-grade pressure vessels before. Use this.

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A "steam trap" should do what you want. There are a few types with different characteristics .

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Any form of gravity trap. For examplea piece of vertical pipe with a large enough diamter will work - liquid gathers at the bottom, diameter need to be large enough to let bubbles pass through the fluid, avoiding plug flow.

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If you are looking for an individually-addressable mirror array, a Digital Micromirror Device (DMD) is what you are looking for. It is used to adjust the brightness of pixels inside a DLP projector by adjusting how much light is display per pixel via pulse-width modulation. By adjusting how fast the mirrors reflect from on to off, the pixels can be adjusted ...

1

We have dry cement bulkers truck running on local roads, feeding dry cement to mixer factory where it is turned into wet mixed cement. Pump air into the truck to 'blow' cement out. This video shows cement and sand are 'blow' by air. Powder (cement/sand) are placed in closed container. Air blow in and powder come out on, says, 2 to 3 inch diameter, tubing. ...

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