# Tag Info

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Short Answer: YES you can. Long answer: A) Limits of continuum mechanics: The continuum model of fluid dynamics is valid only till the fluid behaves as a continuous medium. This is characterized by the Knudsen number. The Knudsen number is given by $Kn = \frac{\lambda}{l_s}$, where $\lambda$ is the mean free path and $l_s$ is the characteristic dimension ...

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Looks like a typical water based central heating system (apart from the scale). You need to balance the flow by restricting flow for the units that get too much. This can be done by partially closing a valve or adding a restrictor for those units. Better if there is some kind of feedback loop to auto restrict when too much water is going through.

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As an addition to @ChrisJohns answer: if you want to limit the effect of the plate oscillations on the motion of the liquid as much as possible you need to make the time scale for viscous diffusion much larger than that of the plate oscillations. If the plate oscillates with an angular frequency $\omega$, the liquid has a kinematic viscosity $\nu$ and the ...

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In order for the fluid to not be affected at all by the movement of the plate it would require either zero friction between the plate and the liquid or for the fluid to have zero viscosity. There is also the fact that the mechanics of moving the plate will inevitably involve some flexing, however small, of the tank and plate and transfer of vibrations into ...

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Reposting my comment for clarity: "Before we get into making this: have you confirmed that a wall thickness of ~0.3mm around the hole is going to be thick/strong enough to resist the pressure required to push the molten steel through your nozzle/hole in the first place? That's very thin.... I think you might have to look at a higher ratio than 60%" Not to ...

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If you are adding fluid at a constant rate a simple michelson interferometer seems like a possible solution. You should get a fringe every $\lambda/2$ m, so ~300 nm. As long as you can sample fast enough it is then just a case of counting the number of fringes to get the distance moved. The only difficulty I can see with this approach is low reflectance from ...

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I believe some laser equipment does have the 20µm that you are looking for: Displacement measurement sensors This product for example has a 20µm precision, but it is said that the precision depends on the optical properties of the surface, so it would require a test for your solution. OD Mini - Compact, lightweight sensor for precise measurement Also, ...

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(340.29(m/s))/(50 μm) = 6.8058 megahertz (or 146.933498 nanoseconds if you prefer) timing that tight is hard to measure on a micro controller, and requires a lot of knowledge to do on a micro processor, but certainly not out of the realm of possibility. That makes (ultra)sonics a possibility. Capacitive sensors are the other method for things like this, ...

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If I understand your question correctly, you are designing and building a small network of pipes or the like that involves different diameters. You have little experience with this kind of design work. You are looking for rough heuristics to help you get started. I assume pipe flow, not open channels. ... when a vein splits in two capillaries, is there ...

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This is a challenging measurement. In my opinion best done with a very good balance. Fully shielded from thermals and vibration, obviously. Use a small container with small opening diameter to limit evap to what will hopefully be under 10% of the final measurement (and we will correct for it more later). A clean 2mL glass bottle is good. Fill bottle halfway, ...

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yes. knowing the surface tension of the fluid and its contact angle with the channel walls, you can select a channel width that does not support two-phase flow, where bubbles and fluid can pass by one another and get mixed up in the channel. For example, the tube diameter on a turkey baster's tip is made small enough so that air cannot flow up in the tube ...

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Actually, 600mL of liquid (water?) is about 600g, not 10kg, so it makes selecting an off-the-shelf balance a lot easier. Likewise, 2ul is about 2mg so a 1mg accuracy should be good enough. Based on this something like this Sartorius balance should do it: Disclaimer: although I have nothing to do with balances, I do work for a company which is part of the ...

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Apply Bernoulli's equation across the two ends. You have pressure values at both ends. Elevation level is same. And substitute velocity(v)=flow rate (Q)/area of flow. Assume head loss to be negligible

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I believe there are 3 mainly options for this case: use microfluidic devices that are made to be reusable; use microfluidic devices that are not are not meant to be reusable but cheaper; devise a protocol of gentle cleaning. The main options for devices made to be reusable are silicon; glass; low temperature co-fired ceramics (LTCC). The main options for ...

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I suggest that you look at one of the follow three options. Ultrasonic Sensor for Texas Instrument (Option 1) To measure liquid level from the bottom of tank one could use a piezo electric ceramic transducer combined with an Analog Front End (AFE) and a micro-controller to measure the liquid level. I believe with some additional work you can achieve your ...

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Looks like you want a typical register, so that sum of the pipe length supply and return is the same for each unit. No guarantee that it works, though. I'll see if I make a drawing if the idea is unclear.

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