Questions tagged [compressors]
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Compression phenomenon in Axial flow compressor
It is quite difficult for me to visualize how axial flow compressors work, as in, how air gets compressed by just flowing through a series of aero-foil shaped stator and rotor blades. How and where ...
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Atlascopco screw compressor unload abnormal sound
We are facing an issue in our GA 75 FF model compressor. During the unload time the compressor is making some abnormal noise, but during the load it is working fine.
When the machine is unloaded after ...
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How to find work done by compressors
Which one is correct method to find work done by a isentropic compressor?
Method-1:
Compressor power = mCpdT
Where m = mass flow rate
Cp = specific heat at constant pressure
dT = Temperature ...
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Can rubber be used as the membrane in a diaphragm compressor with a 1:10 or higher compression ratio?
I've been investing time learning about diaphragm compressors and I can't understand how this particular type of compressor can have a 20:1 compression ratio, and what material could stretch that much ...
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For axial flow compressor, at constant speed, does the required power changes as pressure ratio change?
For an axial compressor running at constant speed/rpm, does the power change as the pressure ratio increases and mass flow decreases (going up a constant speed line of a compressor map)? I am assuming ...
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What is the optimum layout for a hydrogen compressor, that would have least wear and tear on the compressor?
I have been investing time in understanding the layout/schematic of a compressor that would be used for compressing hydrogen to high pressure ratings.
It's not clear to me what is the best design - ...
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How do dual inverter compressors save power and why can they have variable speeds?
As I understand it, most modern air conditions have a rotary compressor with a single rolling piston that's offset from the axis of rotation, causing heavy vibration and limiting RPMs. It then makes ...
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Why do axial compressor stages have to get smaller and smaller to increase fluid pressure?
Why can't we design axial compressor stages of which have the same length? We are adding kinetic energy to fluid and then get it back as potential energy-static pressure. So why do we need that they ...
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Can I use a rotary screw compressor used in refrigeration as a steam compressor?
I need to distill water. Vapor compressors are the best choice. However, difficult to find small scale vapor compressor. I am exploring the feasibility of rotary screw compressor used in refrigeration....
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Can a compressor give the same discharge pressure even if suction pressure varies?
The task is to maintain compressor discharge pressure at 200 bars. The inlet pressure varies with time from 200 bars to 10 bars (emptying a compressed air tank and compressing to transfer it to ...
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Are there compressors that can compress both water and water vapor?
I noticed while reading about compressors that they have various types and are generally made for a specific function. However, are there types of compressors (or pumps) that can compress both water ...
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What is the critical buckling force needed to be applied on a system of made out of two parts?
What is the critical buckling force needed to be applied on a system of made out of two parts?
The parts of the system are as depicted in the picture:
incompressible elastic beam - on top
...
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A 40L compressed air cylinder at 100 bar is emptied in pulses at the rate of 41kg/s. How many such cycles would it take to empty the cylinder? [closed]
I am constructing a blowback gas system where clogged debris needs to be removed with compressed air using compressed air cylinder. 40L compressed air cylinder at 100bar pressure is available as ...
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Pneumatic pressure sensing in a moving air compressor line
I am building an automatic control system for an compressor that stops at a designated pressure. Here's a rough sketch of the system:
The compressor should receive the on signal from the ...
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What drives the mass flow rate in axial turbofan between the compressor and the turbine when compressor is fully choked?
I haven't found the answer in the forum or elsewhere, but maybe I have searched badly, in which case please forgive me in advance.
For a steady nominal operation of a turbofan, I have heard that the ...
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How does compressor ensure that rfgnt exiting the compressor exits at sufficient pressure such as its condensation tmp is always > otsd air temp?
I have very basic knowledge of the refrigerant cycle. I am talking about a Split system Home AC with an air cooled condenser. Assume a basic AC reciprocating or scroll compressor (i.e NOT a variable ...
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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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Compressor ratio and addition of battery cooling loop (chiller) in the existing HVAC circuit
Imagine if i want to change my IC car to an electric vehcile, with the obvious addition of battery, how can i use existing HVAC loop to cool the battery using a chiller. HVAC was obviouly desinged ...
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Retrofitting an old compressor with VFD
For an AC unit, the compressor - GK151PAB - Hermetic type, Permanent split condenser,2 pole, Single phase, Induction motor. This much I know about it. What else do I need to know and how do I find out ...
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Axial compressor: How does it work that the stator vanes diffuse the flow to build up pressure, but also the flow area reduces?
I'm reading about how the stator vanes are diffusors, which diffuse the air flow in a axial compressor to a larger flow area to build up pressure BUT at the same time the compressor shows its overall ...
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How can rod load reversal points determine leakage of valves in reciprocating compressors?
One of the common parameters that is monitored in reciprocating compressors is the net rod load. How can they show which valve has leakage?
For example, if the suction valve of the crank end (CE) has ...
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Understanding air compressor CFM, PSI
I need some help in choosing the right air compressor for my airtable and understanding how CFM and PSI can be used to calculate the system. I read standard google links, pressure drop per linear ft, ...
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Is there a good way to passively dry air in the input of a vacuum pump?
I'm using an a/c compressor as a vacuum pump for small projects that don't need a good vacuum pump, and I'm looking for a way to dry the air in the input, to prevent water from mixing with the oil ...
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how to interpret plots in ISO 10816-8?
In ISO 10816-8 for reciprocating compressors, there are some plots that show the allowable RMS vs. frequency for every part of a compressor.
However, in the text of the standard, it is mentioned that ...
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Confused about how combustor pressure is lower than compressor exit pressure in turbomachinery?
I understand the compressor exit pressure is the highest pressure in all of the turbomachinery, and the combustor is a constant pressure process, and since the combustor P is lower than compressor ...
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Why is pressure in a common rail fuel system so much higher than in an air compressor or supercharger?
Superchargers in cars are bulky, expensive, consume considerable amount of engine's power and yet they generate only about 6-9 psi boost. On the other hand, modern common rail diesel engines inject ...
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Specific heat at constant volume used in non constant volume processes
I have commonly seen that the work for an isentropic compression is written as:
$$
W_{in} = c_{v}(T_1 - T_2)
$$
What confuses me is that since it is a compression (volume is changing) why do we use ...
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Is there a positive displacement compressor that can rival axial compressors in terms of air mass flow to weight ratio?
Is there a positive displacement compressor that can rival axial compressors in terms of air mass flow to weight ratio?
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What is the correct method to remove or tighten this splined "nut"?
This photo shows the input shaft of an air compressor head.
The splined cog-looking disc around the shaft is actually a sort of threaded nut which screws into the larger disc around it. It serves to ...
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why do centrifugal compressors have curved blades?
Why are centrifugal air compressors built with backward curving blades?
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Slow Driving an Air Compressor
Do off-the-shelf air compressors have minimum driving speeds, below which they cannot build the necessary pressure? Reciprocating compressors and scroll compressors are available—is there a difference ...
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Why do high pressure multistage air compressor have different piston diameter sizes? [closed]
I meant like this kind of compressor https://www.bauer-kompressoren.de/fileadmin/_processed_/csm_compressor-block-junior2_b92a76a02e.jpg
also would the compressor reach high pressure if the diameter ...
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Motor part winding start
I have a BITZER compressor type 4GE-23Y-40P, with a part winding start option
Nennspannung = nominal voltage = 380-420
Frequ = frequency = 50
Betr. strom = maximal operating current = 43.9
...
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Is there any side effect to soft start an AC motor?
I have a ground to water heat pump for my home heating/cooling (scroll compressor). The 3-phase 15kW-peak motor can be soft started but this option is off by default.
I'm aware of all the positive ...
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Is it safe to use a 125PSI rated auxiliary air tank with a 150PSI air compressor?
I have a small, 5 gallon, pancake compressor which has a maximum 150PSI rating. Unfortunately, it doesn't have the air capacity to power the demands of an HVLP paint sprayer or a die grinder without ...
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How to decrease Nitrogen gas consumption in Iron & Steel Plant? [closed]
I need to decrease nitrogen gas consumption in iron & steel plant.
Currently it's not possible to measure every dot from steel mill to determine real usage so they use what air separation unit ...
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Why do centrifugal compressors have a higher compression ratio per stage than axial compressors?
It is common for centrifugal compressors to have a pressure ratio of one stage of 3, while axial compressors often have compression ratio per stage of around 1.25. What is the source of that ...
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Work done by compressor to fill a tank
A reciprocating air compressor is used to fill rapidly a $3m^3$ tank at $30°c$ and $1\ bar$. The filing process is governed by $pv^{1.4}=constant$. The effects of kinetic energy may be neglected. The ...
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How do stators in axial compressors work?
How do the stators in axial compressors convert kinetic energy to pressure? Is this equivalent to a water hammer?
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Regarding design of a compressed air delivery system based on a screw air compressor
I want to select a screw compressor for my application wherein I need a pressure of about 18 psig, and 300 cfm at the aforementioned pressure. The compressors I'm finding suitable for the system have ...
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Do stators in axial flow compressors have airfoil geometry?
In axial flow compressors the role of a stator is to gradually change the direction of flow to exchange some of the kinetic energy of the flow into pressure. Therefore it stands to reason that they do ...
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why not put the compressor right next to the evaporator?
the cold line from evaporator to compressor will gain tons of heat on a super hot day even with insulation. if they put the compressor right outside the evaporator, both of the long lines will be hot ...
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Ignoring Mechanical Material Properties and Design Implications, in a Compressor, does the Thermal Density of the Blades Affect Efficiency?
Consider an ideal adiabatic compressor, ignoring the remainder of the thermodynamic cycle. In this case, the heat flow q into and out of the compressor itself is zero, by definition of adiabatic ...
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What is diffusion in the context of compressor?
When studying about the axial compressor, I came across the term 'diffusion' being used to explain the conversion of kinetic energy to pressure, also terms like 'diffusion factor'. What is being ...
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Is there a way to calculate mass flow rate of an axial compressor?
Is there a rule of a thumb equation for the mass flow rate of a stationary axial compressor at sea level, using intake area and RPM? Or do other factors like blade geometry make too much of a ...
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Compressing gas with liquid
This question, in short, is: Can a gas be compressed with high pressure liquid?
As a scenario, imagine a tank full of atmospheric gas at STP. Could something like a pressure washer pump (in this case ...
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Why stagnation temperature doesn't change in stator
I was going through a review of rotary compressor and i understood that the stagnation pressure and stagnation temperature both change in the rotor stage (as energy is being added).I also read that in ...
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Force of Jet from Air Compressor
I want to use a compressor to create a jet of air. At discharge from compressor how much CFM (Cubic Feet per Minute) are enough to create a force that can turn a heavy object (say 40 kg) at 3 rev per ...
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Could I define an isothermal efficiency?
There's an adiabatic efficiency because real processes can't be adiabatic.
I want an isothermal compression (yes, I know an adiabatic compression consumes less work, but my pressure differential is ...
user20096
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Is Scrooge's giant glass dome feasible in real life?
In an Uncle Scrooge (or Scrooge McDuck, not sure of the translation here) comic named "Treasure Under Glass", Scrooge orders a giant glass dome to be manufactured in order to aid his endeavours ...
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