# Tag Info

### Can ultrasonic sound pass through solid medium?

Ultrasound partially reflects when it encounters a medium with different acoustic impedance. It behaves like light and obeys Fresnel equations. If the angle of incidence is smaller than the total ...
• 1,035
Accepted

### Ideal funnel design for powders

The problem you have is more complicated than you think. Any industry that deals with the storage and movement of granulated/powdered materials has to deal with this and most have unique solutions. ...
• 9,722

### Established Patterns and Designs for Measuring Powder by Volume

I suppose you need some kind of powder doser or volumetric feeder It might work on measuring time. Very easy principle, you need valve (maybe solenoid valve or for some sort of flap door) and timer ...
• 314

### Transfer of low density solids

Conical hopper with gate control.
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### Given flow rate of an orifice at one pressure, how do I calculate flow rate for a different pressure?

Here is a reference from RoyMech, see section under "Orifice Flow Meter". The setup has the orifice placed in a pipe. Below is a similar, perhaps simpler, expression, from Jobson 1955, part ...
• 1,571
Accepted

### Given flow rate of an orifice at one pressure, how do I calculate flow rate for a different pressure?

Flow rate is directly proportional to the square root of pressure. So for any given orifice, all else being equal, $\frac{GPM}{\sqrt{PSI}}$ is constant. Technically PSI here is the pressure ...
• 171

### Pneumatic Can Crusher (Number of holes allowed for crushing plate)

The number isn't as important as total surface area of the holes - it doesn't need to be greater than the can opening for the remaining pressure resistance to be entirely negligible. Decision on the ...
• 6,115

### Gear pump has backflow and does not stop forced flow

You will probably need to install a check valve (or manual valve) to prevent the backflow, and rebuild the pump heads periodically. Over time, the gears wear down and small gaps form. This both leads ...
• 41

### Why doesn't steam/water flow backwards from expansion in power plant feedwater pump/boiler?

Google "Rankine cycle". The boiler operates at an elevated pressure (sometimes several atmospheres). But because steam at a given pressure is many times bigger than liquid water at the same pressure,...
• 2,692

### When designing a carburetor, is the air to fuel ratio calculated or just experimentally adjusted?

Yes. The range of airflow required is established by the swept volume of the engine and the max rpm. That will then define the pressure drop and venturi needed - which is often controlled by a moving ...
• 15.9k
Accepted

### Liquid Level Control System Resistance

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 Ď„ = RC. In your case C ...
• 10.9k

### How can I ensure steady flow to all the valves?

One basic way is to adjust the valves, the dry ones fully open and the ones bleeding all the pressure just slightly open, or even restricted permanently by a smaller size bushing just before the valve....
• 22.6k

### How can I ensure steady flow to all the valves?

The most precise way to control flow is with valves/flow regulator. The main problem is the cost. Although, its a very basic component and its not too costly if you have too many outlets the cost ...
• 24.4k

### Given flow rate of an orifice at one pressure, how do I calculate flow rate for a different pressure?

If you know the external diameter and orifice diameter, From Wikipedia the orifice plate equation : $$q_m =\frac{ C_d}{\sqrt{1-\beta^4}}\epsilon\frac{\pi}{4} d^2 \sqrt{2\Delta p \cdot \rho_1}$$ ...
• 24.4k
1 vote

### Would the volume of water usage change if we increase water pressure using a booster pump? Not changing pipe diameter, length or viscosity

Yes, you would use approximately 1.3 times more water. To calculate the volume you need to enter the pipe dimensions, roughness, static head, and friction head in a, readily available, online app. ...
• 22.6k
1 vote

### How can I measure the flow rate of CO2 gas from two different canisters?

Well, technically you would use absorbent like Ca(OH)2 and weight it, to measure how much CO2 you got, through a CO2 permeable membrane to avoid H2O. But in your case its much simpler to just weight ...
1 vote

### Determine the length of the tube

If the flow rate is 5ml/min, and you want to know how long a tube it will take 1 min to pass through, youâ€™re effectively asking how long a tube contains 5ml. Volume of a cylinder is $\pi*r^2*h$. 5ml ...
• 7,761
1 vote
Accepted

### Relative improvement in flow from diameter change with sub-milliimeter tubing

You made a small mistake if we are going to use Poiseuille's law. $Q_{final}= Q_{initial}\Delta r^4 \rightarrow \Delta Q =(\frac{r_{final}}{r_{itial}})^4$ Plugging your numbers, \$ Q_{final}=Q_{...
• 22.6k
1 vote
Accepted

### Proper Flow Meter Installation

The flow meter needs to be installed such that it is always under pressure (in normal operation). That is it should be after the regulator but before the on/off valve. That way you will get no surge ...
• 318
1 vote
Accepted

### How can I confirm nL Volume Measurement for Pump and Sensor Calibration

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 ...
• 1,571
1 vote

### Cheapest way to measure gas flow (mass)?

By knowing the volume flow rate of a gas , you can also find the mass passing through a cross section area for certain thermodynamic conditions.
1 vote

### Do pressure regulators restrict the mass flow rate?

Your assessment of the situation is correct - the solution is of course to specify a pressure regulator with a large enough orifice that it does not cause you a problem. Pressure regulators are ...
• 7,761
1 vote
Accepted

### Flow control experiment

The Objective of this experiment is by the way to investigate the linearity and hysteresis of the flow sensor. The key word here is hysteresis: the output of the sensor at the same flow rate might ...
• 1,841
1 vote

### Water loop with a drop output?

Drip irrigation parts cost about five cents a piece. They come in fractional gallons per hour at 25 psi. So pump the water into the tank from the bucket via a drip head, and use a simple float valve ...
• 4,850
1 vote

### Water loop with a drop output?

Yes, you definitely can do that. There are small filler pumps that will automatically kick into power when the water falls below the present level and the floater activates the pump. So you can have ...
• 22.6k
1 vote

### Modeling Water Flow Through Saturated Medium

Saturated flow through sediments is governed by Darcy's Law, which relates the pressure drop across the porous medium to the permeability of the medium to calculate the fluid flow rate. The fluid ...
• 111
1 vote
Accepted

### Programming a gas mass flow controller rig

My best stab at this would be to attach parallel inputs of: Gas1(100psi) -> Flow Meter1 -> Valve1 -> Manifold Input1 Gas2(100psi) -> Flow Meter2 -> Valve2 -> Manifold Input2 Gas3(100psi) -> Flow ...
1 vote

### What should be the density of a compressed gas while measuring the flow rate using Rotameter?

In, compressible flow, the mass flow rate remains constant throughout the flow. But volume flow rate is changed according to the local velocity and area of cross-section. So one can calculate the ...
• 511
1 vote

### How does pressure drop occur across a pipe

The Bernoulli Equation can be considered to be a statement of the conservation of energy, i.e. the internal energy of the fluid remains constant. This can be useful for certain calculations e.g. the ...
• 7,761
1 vote

### How to control the level in multiple connected tanks at the same time?

You are dealing with a multi-input multi-output system (MIMO) system in which case you can't in general apply the same techniques as for single-input single-output (SISO) systems. If you are dealing ...
• 1,663

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