Questions tagged [gas]
The gas tag has no usage guidance.
83
questions
0
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1answer
6 views
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 ...
-1
votes
1answer
35 views
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 ...
1
vote
2answers
25 views
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 ...
-1
votes
1answer
22 views
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 ?
2
votes
1answer
51 views
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 ...
4
votes
4answers
2k views
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 ...
1
vote
0answers
18 views
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 (...
-1
votes
1answer
50 views
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 ...
1
vote
3answers
47 views
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 ...
0
votes
1answer
39 views
How to predict out wavelength emitted from gasses
I'm trying to figure out which gas emits a specific wavelength when excited.
Say I want to develop an LED that emits a certain wavelength.
How would I figure out which gas emits that specific ...
0
votes
0answers
13 views
Determine gas orifice size based on factory sea level orifice (range oven)
I have a natural gas unit that is being used at a non sea level application. It comes with #36 orifice size, and gas is at 5"WC. With that information, how would one determine the proper orifice size ...
2
votes
1answer
80 views
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 ...
1
vote
1answer
27 views
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 ...
2
votes
0answers
61 views
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 ...
0
votes
1answer
23 views
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 ...
0
votes
2answers
62 views
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
...
2
votes
0answers
17 views
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 ...
1
vote
1answer
20 views
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 ...
0
votes
2answers
978 views
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\...
1
vote
2answers
140 views
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.
...
0
votes
0answers
22 views
Modeling Friction-reduced Pressure Drop in Natural Gas Flowing along a Horizontal Cylindrical Trunkline (Pipe)
I am seeking some help related to part of a project I am currently working on, where I require to (data-driven) model the pressure drop due to friction for natural gas flowing along a horizontal ...
-1
votes
1answer
92 views
Classic Thermodynamics: Ideal gas question
The question is in the attached picture. I know how to solve the first part of the problem, but the second part confused me a lot.
Now when the oven (system) is unsealed, doesn’t make that an open ...
2
votes
0answers
42 views
Liquid phase gas flow through valve
I have been trying to figure out how to calculate the required dimensions for liquid phase gas through a solenoid valve. Many companies (Swagelok, Bürkert, Asco) provide "Flow coefficient calculators" ...
0
votes
1answer
28 views
Safe, cheap method to dissolve nitrogen in small batches of water (10l)
I am interested in creating a nitrogen infused drink. I want to be able to make small batches of my drink (its not coffee) and testing the market before having to buy expensive equipment.
I think a ...
3
votes
1answer
65 views
Would pumping down (below 0 psi) on a gas cylinder regulator cause it to break?
Would pumping down on a gas cylinder regulator cause the needle of the valve to break since it’s trying to go below zero? Would this also cause a problem with the regulator itself?
I’ve included the ...
5
votes
1answer
68 views
Easily compute a good approximation of heat conductivity of cooled semi-vacuum (water vapor + air)
I am preparing a classroom demonstration about heat, including a demo of how a satellite loses heat only radiatively, since it's flying through a vacuum. I'd like to make the vacuum-production ...
0
votes
1answer
359 views
Programming a gas mass flow controller rig
I'm trying to upgrade a multiple gas flow controller, which must be capable of controlling the mass flowrates of three gases independently through one outlet line to our system, and am in need of a ...
1
vote
2answers
56 views
Is there an optical technology able to measure the temperature of dry air?
Optical IR sensors are able to measure the surface temperature of solids. But is there a range of the EM spectrum that can accomplish the same for measuring the temperature of nitrox (dry nitrogen, ...
0
votes
1answer
50 views
Relationship heat rate with capacity
I am an economist, so please keep replies simple ;)
I am searching for the relationship between heat rate and capacity for gas-fired power plants. Here is what I refer to as heat rate, i.e. the ...
1
vote
0answers
26 views
Equation for temperature of gas at Joule-Thompson Inversion State
Assume that a gas obeys the following equation of state:
$\nu = {\frac{RT}{P}}-{\frac{a}{T}} + b$
Where $a , b $ are constant.
Derive an equation for the temperature at the Joule-Thompson ...
1
vote
1answer
95 views
Which type of sensors to analyze polluting gas from vehicle emissions
I am thinking to develop a remote-sensing applications for vehicle pollutions. In such cases generally expensive optical IR and UV devices are used because more precise. These devices are generally ...
2
votes
0answers
39 views
Oxygen sensors in trace gas environments
Do Oxygen lambda sensors (used in automotive applications) work in trace gas environments?
My requirements for a trace Oxygen gas sensor:
The sensor must be capable of working in an inert gas ...
2
votes
1answer
564 views
What are the differences between compressor stations, pump stations, and booster stations?
I am doing some research on impacts related to natural gas compressor stations. In some states, I've received data for compressor stations alongside other facilities in the oil and gas world. These ...
0
votes
1answer
94 views
maximum capacity factors of combined cycle gas power plants
What is the maximum annual capacity factor that can be expected of a CCGT plant? I see in US in 2015 the average was about 0.56, but can it be higher? I guess it needs some time for maintenance but I ...
2
votes
2answers
498 views
What is a reference that i can use to find the interpretation of a symbol in a gas line schematic?
I have a schematic for some gas lines in a wafer processing unit. One of the symbols which occurs is a circle with an x in it that has the left and right quarters filled in to form two black ...
0
votes
1answer
150 views
Will natural gas or propane generators also run off of methane?
I'm looking at building a sustainable energy project that will convert biogas (methane) into electricity. I haven't found any biogas or methane electric generators for sale. It seems that there are ...
0
votes
2answers
34 views
Measuring gas flow from a low-output device
My lab uses a home-built biomedical instrument that acts as a ventilator for test-subjects. In other words: our device combines nitrogen and oxygen gases and pumps them down the line at a specified ...
1
vote
1answer
79 views
Why is gas pressure specified instead of mass flow?
Clarification: This question is all about the gas supply to the water heater. It has nothing to do with the water supply.
My hot water heater specifies 5.5-10.5 W.C. (water column inches) of pressure....
2
votes
2answers
740 views
Lpg cylinder to compressed air tank
I am building a small robot having pneumatic system. I am using 12v car tyre inflator as my compressor.But i didn't find any 3ltr to 6ltr standardrd air tank. Can i convert my old 3ltr lpg tank into ...
-1
votes
2answers
88 views
why doesn't soda go flat immediately after opening? [closed]
so, soda is under pressure and has gas dissolved in it. But, when you open it, the gas is still dissolved in it. But, if we wait a few hours, the gas has escaped into the atmosphere.
What factors ...
1
vote
1answer
51 views
Is there any option other than a gas welder
I want to repair a dent in a piece of cast iron with brass. I want to fill the site with brass.
For some reason, I want to do it by myself. I can buy an instrument for this work in a limited budget(...
2
votes
2answers
45 views
Can I improve this exhaust gas probe to be immune to pressure changes?
I'm designing a probe to provide a stable and continuous stream of exhaust gas sample to an analyser. The probe has to be inserted into the exhaust for about 20–30 cm to keep outside air from entering ...
0
votes
1answer
71 views
Natural gas boiler Vs. Electric Heater efficiency
If a facility buys natural gas at 8 dollars/Mcf to provide heating from an 85% efficient natural gas boiler, what is the equivalent cost of electricity ($/kWh) for a 95% efficient electric heater?
I'...
1
vote
0answers
53 views
Is there a 5% range CO sensor with a response rate higher than 1Hz?
I'm building a portable emission analyser which measures emissions from a tailpipe, to aid in troubleshooting and tuning an engine. For this, I need a $\text{CO}_{2}$ , a $\text{CO}$, and an $\text{O}...
0
votes
1answer
447 views
Determining gas properties in a steam and air gas mixture
I have a gas mixture (steam and air) contained in a tank.
I know the tank pressure ($P$), temperature ($T$) and the massic air fraction ($x_a$).
I would like to determine the density of both gases ...
0
votes
2answers
83 views
Thermodynamic, ideal gas problem
I already know solution, I just want to understand something in part b.
A vertical cylinder fitted with a piston contains air initially at 120kPa and 100 celcius. The piston is restrained by a set of ...
1
vote
1answer
312 views
What ramping constraints for gas plant - CCGT, combustion and steam turbine?
I am using the publication Current and Prospective Costs of Electricity Generation until 2050 to source ramping constraints for an economic model of three different gas power plants - CCGT, combustion ...
1
vote
1answer
646 views
Difference between gas combustion engine and gas turbine?
I am a non-engineer and I am using a gas power plant data base. Some plants listed are of the type "combustion engine", some of the type "gas turbine", some "steam turbine" and some "combined cycle". ...
1
vote
0answers
89 views
Creating a “pinhole” small enough to allow only one molecule to pass through
Consider a "cartridge" of sorts. Is it possible to construct a "pinhole" in the cartridge such that only one molecule will pass through at a time? If so, what sort of equipment would I need to ...
2
votes
0answers
52 views
Ambient helium level monitoring
I am looking for a solution to monitor and log ambient He levels down to 50-100ppm.
The detector is meant to be installed in an experimental hall where a large number of Photo Multiplier Tubes are ...
