Questions tagged [gas]
The gas tag has no usage guidance.
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Question about cylinders of mixed gases (nitrogen and carbon dioxide)
This is probably a question more suited towards the home brewing stack exchange, but I'm interested in some of the engineering and physics aspects of this as well, so I'll just try asking it here ...
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Gas leak rate from a pipe
I am trying to find out how to calculate the leak rate of gas (composed of mostly methane at around 30degC and 150psi) from a pinhole leak (~5mm) to the atmosphere in a pipe where you do not have the ...
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How do I purchase cylinders of Hydrogen (H2) gas for person use?
I'm interested in building small model airships, and I would like to purchase a cylinder of H2 gas to fill the envelopes with as is far cheaper and more effective than helium. I've contacted some ...
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Is it possible to determine how far a vacuum cleaner hose can suck an object in from?
I'm working on a project similar to a vacuum cleaner, where I have a suction pump connected to an open ended pipe that has a negative pressure gradient such that things are being sucked into it with a ...
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In UK, are new smart energy meters secure?
I have read this newspaper article about insecurities in smart meters.
Some quotes from the piece:
To communicate with the utility company, most smart meters use GSM, the 2G mobile standard. That has ...
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Is there a filtration mechanism that allows nicotine molecules to pass and not particulate matter?
I was wondering if an equivalent of the vaporization of tobacco could be achieved by normal combustion but passing the smoke through a filtration mechanism that only allows pure nicotine vapor through ...
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Solar distillation of sump pump water and the issue of Radon gas
Lately I have been thinking about designing and building a solar-powered water distiller that would be placed close to my house in my backyard.
One thought that I have is installing a bypass valve on ...
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What Fitting is This?
This is on a propane tabletop flame. This is the input. The thread pitch is 18/inch and the major diameter is .525 inches measured.
I can thread a 1/4 NPT onto this, but this is not tapered.
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Passive gas mixing valve that takes fixed ratio of gas from two different inputs
I am designing a device that requires a gas (air) valve that takes the same volume of gas from two different input ports IP1 and IP2.
The output port OP will have lower pressure than both of the ...
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Does a typical domestic combination boiler have different burn rates?
For a typical domestic combination boiler, does it have different burn rates, in a similar way that a gas hob ring has? My understanding is that the trigger for whether such a boiler comes on or not ...
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How to use natural gas mostly sourced from ʟɴɢ on appliances designed only with propane burners?
Given identical pipes, and given in Europe propane from bottles is distributed at 34millibars (G31) and 20millibars for main gas (G20 standard).
Using the Wobbe index, how much natural gas should be ...
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If you shut down a gas pipeline for a few months would you fill it with gas at full pressure?
This is of course inspired by the Nordstream gas pipelines in the Baltic Sea. When it was decided that Nordstream 2 would not start operating after construction finished they still filled it with ...
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Power To Compress Ideal Gas In A Piston
I am familiar with isothermal and adiabatic ideal gas compression problems where a force is exerted on a piston of area A to move it some displacement in order to calculate work done. However I am ...
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Sizing heat exchanger for cooling humidified hydrogen
I have a chemical reactor producing a humidified stream of hydrogen gas and I need to cool it down to near ambient temperature using a heat exchanger, say 25 degrees Celsius.
Within the reactor I ...
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Gas expansion by turbine and by orifice
What is the difference between gas expansion by turbine, and gas expansion by orifice. Because in turbine we get useful work, while in orifice we don't.
Please show PV (and or TS) diagram path for gas ...
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How would a gas flow switch react to falling pressure in the gas supply?
There's currently an ongoing discussion (not decision!) in Germany if households could be cut off from gas supply come winter, to make more natural gas available for industry. Of course media is full ...
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Work done during transient filling of a tank
This question stems from the online thermodynamics notes provided by web.mit.edu. I'm having some trouble understanding the example given of air expanding into a vacuum.
Consider the transient, ...
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What contributes to the energy cost of multistage compression at high discharge pressures?
I'm getting into hydrogen compression from a theoretical point of view and am looking for a model to describe the energy requirements.
I've gathered, that hydrogen is often compressed with piston ...
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Gas temperature control with a mixing chamber
I am currently trying to figure out how to set up an automatic controller in order to get a precise air temperature at a specific flow rate with a hot and fresh air mix system.
Picture the system like ...
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Applications of CO$_2$ sensors [closed]
I am working on a project where I am creating a new type of CO2 sensor. (I can't give details on the functionalities). I am looking for applications to showcase the capabilities and the usefulness of ...
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Properties of air and gas mixture
While studying a heat exchanger, I have encountered a hydrogen rich fluid stream (enters at 90° Celsius and exits at 120° Celsius) which has composition given in the following form:
Air Humidity/Fluid ...
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Can flow rate of a small gas flow be controlled by a valve that is opened and closed rapidly in a certain frequency?
Can flow rate of a small gas flow be controlled by a small solenoid valve that is opened and closed rapidly in a certain frequency?
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Constant Pressure Variable Volume Tanks
Do constant-pressure variable-volume tanks exist in industry? I've read about water-column and membrane-based designs, do either of these exist as OTS components, and where would one get them?
Edit: ...
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Sampling System Line Flow Rate
I'm an application engineer for sampling system products. Currently, one of my customers wants to measure their gas sample composition and create a new sample system to achieve it. They don't have any ...
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Calculating gas volume in a gas-liquid system/pressurized vessel
There is water in a tank and the tank is connected to a piece of piping that has a volume of 2.5L.
The headspace above the water is pressurised by using air, to a pressure of 3 bar (a).
What happens ...
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Valves and plumbing size
I'm building a liquid rocket engine and we're using kerosene and oxygen as our propellent. Now my question is what pipe size should we use? My flow rate for kerosene is 0.160 Liters per second and we ...
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CFD simulation of an Air and Oxygen gas gradient in a microfluidics device
I am in the process of manufacturing a microfluidic device for use in research, and would like to do a CFD simulation of the interior of the device to see if an oxygen gradient is formed.
The idea is ...
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At what negative pressure do gases separate from water?
According to this video, when a valve is quickly shut, the water hammer effect can lead to a high negative pressure in a pipe downstream. This leads to dissolved gases coming out of solution with the ...
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Gas kitchen stove in skyscrapers
I have watched a property tour around an apartment in the Steinway Tower (NY) on YouTube and I noticed one detail that bugs me, namely gas stoves.
In Poland it is very uncommon for new blocks of flats ...
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How can I measure the flow rate of CO2 gas from two different canisters?
I am looking for some help regarding one topic. I am designing one soda maker and thinking to include a 12g CO2 canister into it as my design only allows that size to incorporate . Now I know ...
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Part to pierce the valve on a 16g CO2 cartridge and connect to a Solenoid valve
The specific part that I’m after is something that can connect to a solenoid valve and a CO2 cartridge that will break the seal on the end of the CO2 cartridge.
The solenoid valve connection is ...
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Are gas distribution networks tree-like?
I was wondering, if it is justified to say, that gas distribution network graphs (primarily in Europe) are typically tree-like. By gas distribution networks I mean municipal and regional distribution ...
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Is there a valve design or system that can do this?
I am trying to come up with a way to bleed air from a tube to avoid air (gas) from reaching the other end of the tube. Is there a way to do this automatically? It must be able to work in all ...
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Can I calculate the amount (mol or mass) of water in a gas, in a heat exchanger, if I know the partial pressure of the water?
Is it possible to calculate the amount of water (mol, mass...) in a gas, in a heat exchanger, if I know the partial pressure of the water? The stream through the tubes is mainly benzene and ...
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What is the purpose of combustor in a gas turbine
I have read online that a gas turbine converts the chemical energy in the fuel gas to mechanical energy of the turbine blades. The way I see it, because of this hot air one would have to go for heat ...
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Should pressure vessel head be thicker than wall [closed]
I wondering should the head of a rectangular pressure vessel cylinder be thicker than the wall ?
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Determining required pressure drop for choked flow conditions to be met
I have pipework system with an inlet pressure, $P_0$, which passes from a pipeline of fixed diameter, $D_0$, through a tee with reducer to a smaller diameter pipe, $D_1$, before returning to another ...
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Is it possible to increase the heat output of a gas stove by connecting two gas supply canisters to it at the same time, and is it safe to do so?
Here's a typical outdoor gas stove:
It is fed by a low-pressure gas supply in the form of a camping cartridge or via an LPG cylinder connected to a low-pressure regulator (around 30mbar) like this ...
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CO2 probe measuring at temperatures up to 150 °C
I'm looking for a $CO_2$ measuring probe (analog current output, digital out: RS232/485 - probe will be connected and transferring real time data to the data logger) that would operate up to 150 °C (...
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Does the shape of a car really matter for how much gasoline it drinks?
Let's say that we have a mid-1950s "gas guzzler". Now, we take away the exterior "shell"/chassis and replace it with a modern car's. That is, it will visually look just like a modern car from the ...
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Is there a type of check valve that allows gas to flow in both direction but stops liquid from flowing back?
I have a pressure regulator to maintain a specified pressure in a vessel that also contains a liquid. The regulator can pressurize or relieve pressure of the vessel. I want to prevent the liquid from ...
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Do pressurised cans still pose a risk to bursting in normal conditions, but after being exposed to heat?
We're planning on shipping some items from the US to Australia as you cannot get them here, that being:
https://www.chewy.com/sentry-stop-that-noise-pheromone-dog/dp/56486
I have been in contact ...
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Valve/Filter allowing through gas only, no liquid
I need to devise a way to ensure only NG passes through a pipe, and no condensates or other liquids. It is ok to shut down the pipeline if liquids would be detected. The dimensions involved are small ...
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Injecting CO$_2$ into water: how does injection work?
I've been wanting to design my own water carbonation device for a while.
For reference, I've been looking at devices like the Sodastream, which injects pure CO$_2$ into water to dissolve it with up to ...
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What kind of sensors to be used to measure the carbon dioxyde concentration?
I'm planning a thought project for measuring the C02 in a room (at office namely), and communicating its results to a computer.
But I'm blocked at the early stage: which sort of sensor and which is ...
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Ideal gas law, theory vs reality
I am trying to get an idea of the amount of hydrogen that I can store in some pressurized steel tanks underground.
Based on the ideal gas law PV=nRT
I did a simple calculation
pressure = 200bar
...
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Parts needed for controlling vacuum line pressure with pressurized nitrogen
I'm trying to assemble a simple setup where a line which is typically under vacuum can be pressurized by an external nitrogen supply, with this pressure regulated to less than 1 bar absolute (let's ...
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How to contain air ions inside a chamber without loosing their charge?
I would like to create an experiment where I would hold ionized air molecules. Most likely negative O2-1 ions. I am looking for the most appropriate enclosure so that the ions do lose as little of ...
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Calculating mass of gas in container
Given pressure is directly proportional to density, my understanding is that you can use the pressure of gas in a container to calculate the mass of the gas in the container. My reasoning being;
$p=k\...
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Cheapest way to measure gas flow (mass)?
I understand that there are quite a few fairly simple and cheap methods to measure the flow of gas in terms of volume, allowing you to get a flow rate in terms of litres per minute for example.
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