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    How to assign thermodynamic properties after splitting two phase into gas and liquid



    Looking at a simple TXV system. Lets assume after the TXV we seperate the gas down one pipe and the liquid down another. The question is how do we assign the correct thermodynamic properties to each fluid when it gets to end of its pipe.

    The gas we want to do work on like heat it or compress it but before we can see where it ends up and predict its temperature and pressure we need to know from where we started? So do we move the gas out of the middle of the bell on a PH diagram to its edge and similarly do we move the liquid back to the saturated liquid line to gets its new properties?

    Simply jumping out of the bell interior means that the enthalpy and entropy both make huge changes without any process being done. Hmmm

    Your thoughts welcome

    Chef



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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by Chef View Post
    Looking at a simple TXV system. Lets assume after the TXV we seperate the gas down one pipe and the liquid down another. The question is how do we assign the correct thermodynamic properties to each fluid when it gets to end of its pipe.

    The gas we want to do work on like heat it or compress it but before we can see where it ends up and predict its temperature and pressure we need to know from where we started? So do we move the gas out of the middle of the bell on a PH diagram to its edge and similarly do we move the liquid back to the saturated liquid line to gets its new properties?

    Simply jumping out of the bell interior means that the enthalpy and entropy both make huge changes without any process being done. Hmmm

    Your thoughts welcome

    Chef
    Gents, to save time & make ease of reading, Jump to; # 103

    Just drop the txv & sounds like flooded plate heat exchangers with low pressure vessel, chilled water system, if you plot that on a chart it will come back as you described,

    (other than that I am lost for what your trying to acheive)

    The liquid remains in the heat exchangers, with some in the vessel, then the boiled of vapour is piped from the top of the vessel back to compressor

    You can not get much work out of the vapour compared to the liquid, transfered to vapour

    What are we trying to acheive ?

    R's chillerman
    Last edited by chillerman2006; 24-08-2011 at 06:28 PM.
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    i posed that question to "ask jeeves.com"(other similar sites are available)and the reply was-if u chop out the tev then each seperated pipe is going to p*ss out refrigerant.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by install monkey View Post
    i posed that question to "ask jeeves.com"(other similar sites are available)and the reply was-if u chop out the tev then each seperated pipe is going to p*ss out refrigerant.
    I dont know for sure, you can not believe everything you hear on the net, (as tex found out) just asked the mrs though & she has confirmed "you would loose the gas & some oil"
    Last edited by chillerman2006; 20-08-2011 at 12:32 AM.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post

    (other than that I am lost for what your trying to acheive)

    R's chillerman
    So I split the gas and liquid but what h and s values are then given to each seperate flow. In a simple example lets have the evap at 1 bar and x=0.3
    The gas/liquid is at h=231 and s=1.13 but now rip away the gas and suddenly it has a value of h=384 and an s=1.75 but we have not done anything except seperate the flows and we see a huge change in properties?

    This means the gas/liquid together has one set of properties but when seperated they both have differant set of properties. What are the rules for reassigning the properties to each of the seperate streams.

    Simply I want to know where to plot the 2 seperate streams on a PH diagram.

    Chef

    install monkey - seems Jeeves is way up to speed on this topic eh!

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by Chef View Post
    So I split the gas and liquid but what h and s values are then given to each seperate flow. In a simple example lets have the evap at 1 bar and x=0.3
    The gas/liquid is at h=231 and s=1.13 but now rip away the gas and suddenly it has a value of h=384 and an s=1.75 but we have not done anything except seperate the flows and we see a huge change in properties?

    This means the gas/liquid together has one set of properties but when seperated they both have differant set of properties. What are the rules for reassigning the properties to each of the seperate streams.

    Simply I want to know where to plot the 2 seperate streams on a PH diagram.

    Chef
    chef

    I am struggling here with what you mean & what your trying to achieve

    As far as plotting the cycle on a chart, your vapour is to the right, your saturated vapour is in the middle & the liquid is to the left

    but I cant see how this can be plotted without combining temperatures with pressure or why you would want to do this

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    A system needs to be balanced and an equilibrium from the energy transfering into an evaporator needs to balance out with the energy leaving the condensor, if you remove all vapour, what are we doing pumping neat liquid round a system (& as you mentioned) no work is being done

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Energy can niether be created or destroyed just transfered from one form to another, with this in mind and my previous posts combined

    The wheel has been created and the rules of thermodynamics are set in stone

    My question is what are we trying to acheive ? (the impossible)

    I dont understand
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Come on chef

    not many are like me & dont care what others think !

    am not at this level, not at design level even

    and do not see what benefit it is

    this could be here a while as 60+ views already & nobody has a clue
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Hi Chef, good to see you are looking into our little problem.

    As far as enthalpy goes, if the vapor is just that vapour (full seperation) then the enthalpy will be on the saturation point of the curve. But how is entropy effected.???????

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    Come on chef

    not many are like me & dont care what others think !

    am not at this level, not at design level even

    and do not see what benefit it is

    this could be here a while as 60+ views already & nobody has a clue
    The question is not based upon what you would expect!

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Well chef

    I could repeat all of what I have now been told & pretend I fully understand

    But I have to work through some of it

    I'll let you know I have been put on the right track though

    utilizing the flash gas potential for generating flow through an evaporator

    gaining maximum velocity through the evap coil which makes it 1 to 1 efficient

    r's chillerman
    Last edited by chillerman2006; 20-08-2011 at 03:28 AM.
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    well chef

    i could repeat all of what i have now been told & pretend i fully understand

    but i have to work through some of it

    i'll let you know i have been put on the right track though

    utilizing the flash gas potential for generating flow through an evaporator

    gaining maximum velocity through the evap coil which makes it 1 to 1 efficient

    r's chillerman
    ---------no--------

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Well Mr Chef

    I shall thank you for bringing this to my attention

    I have and will continue to gain from this

    As I said earlier I am not at this level

    But will be following the progress & eagerly await the outcome

    To see what can be acheived at such a level, I am yet to fully understand

    And thankyou Mad for setting me straight, I can sleep now today

    Good night Gents
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post
    Hi Chef, good to see you are looking into our little problem.

    As far as enthalpy goes, if the vapor is just that vapour (full seperation) then the enthalpy will be on the saturation point of the curve. But how is entropy effected.???????
    Mad

    Maybe 4:00 here, I'm not sleeping till I have exhausted my understanding or lack of

    Trying to understand here full seperation

    And by this I mean on the chart the point of seperation I can see

    With (as you said) enthalpy following the curve of saturation/vapour

    enthalpy tails off at the point of the opposite curve saturation/liquid

    So (correct me) this point where enthalpy tails of is the point of entropy

    The point of diss-order prior to order and the point at which you need to achieve full seperation

    If this is correct, how do you physically get to this point to acheive seperation in the first place ?

    And how would this be put to use ?

    What sort of system (design) if possible to get to this point & what would this acheive ?
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Firstly read the first question, there is no mention of an evaporator.

    So without thinking any further than what I say next

    We have an open flash economiser vessel, liquid in, liquid out vapour out. what are the properties of all. Are there any strange things happening???

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post

    We have an open flash economiser vessel, liquid in, liquid out vapour out. what are the properties of all. Are there any strange things happening???
    There is no stage of saturation
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    There is no stage of saturation
    ????????????????????

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    There is no stage of saturation
    No there must be (surely) a point of saturation, just this is somehow minimal as you have found a way for full seperation
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    No there must be (surely) a point of saturation, just this is somehow minimal as you have found a way for full seperation
    Yes seperation is an issue, but not the issue in hand (it must happen in an open flash vessel anyway) We are onlt talking about internal energy, (law of conservation)

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post
    ????????????????????
    There is stage of saturation, the point of entropy, where diss order becomes order once more , the point at which you achieve full seperation ??
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    I am following I am just trying to work out where we are tranfering the energy from and to - to enable enough to achieve this full seperation
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    high pressre liquid in (from cond) reduce pressure, what happens?

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    The liquid entering the flash econimiser has a specific heat/energy & at the point of seperation you are transfering the heat/energy from the liquid into the vapour, in effect subcooling the liquid
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    The liquid entering the flash econimiser has a specific heat/energy & at the point of seperation you are transfering the heat/energy from the liquid into the vapour, in effect subcooling the liquid
    Not quite, apart from liquid head there is no sub cooling, and you are converting some liquid into vapour to keep the energy balanced. What then are actual properties of each exit stream. This is the question in hand?

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    The liquid entering the flash econimiser has a specific heat/energy by flashing of some lquid into vapour, you lower the pressure/temperature of the remaining liquid transfering the heat/energy to the vapour, subcooling the remaining liquid...
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    The liquid entering the flash econimiser has a specific heat/energy by flashing of some lquid into vapour, you lower the pressure/temperature of the remaining liquid transfering the heat/energy to the vapour, subcooling the remaining liquid...
    You are cooling the liquid by vapourizing, the pressure has dropped, so the liquid is at saturation, hence is not sub cooled.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post

    We have an open flash economiser vessel, liquid in, liquid out vapour out. what are the properties of all. Are there any strange things happening???
    Liquid in - saturated liquid

    liquid out - liquid only

    vapour out - vapour only

    neither are superheated or subcooled

    & therefore

    to go back to the question from Chef - #5

    They would both be plotted on a ph chart along their respective lines at the point of saturation

    ???????????
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    Liquid in - saturated liquid

    liquid out - liquid only

    vapour out - vapour only

    neither are superheated or subcooled

    & therefore

    to go back to the question from Chef - #5

    They would both be plotted on a ph chart along their respective lines at the point of saturation

    ???????????
    Yes one would think so?????, unless someone can show something else??? and this is all chef was asking

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Thanks Mad


    I understand what you mean at last

    Talk about - I beat around every bush first & need spoon feeding

    Thanks Chef, if you had not have posted that question, there would still be that gap in my knowledge


    (But scrolling back up - no-one else came along and attempted it did they)

    Back on track

    So what you's were looking for was not me butting in, but someone on par with yourselves, who maybe could have come up with that something else that may or may not be there ?
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    no butting in is good, if you do not ask, then you will not get an answer. No one knows everything,
    " the more I know, more I know, I know nothing"

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post
    no butting in is good, if you do not ask, then you will not get an answer. No one knows everything,
    " the more I know, more I know, I know nothing"
    Yeah, thanks Mate

    Got a new signature too now
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    The methodology for solution will very much depend on the two-phase model you select. Flow regime for two-phase flow can be rather interesting & the theory is far from settled.

    With different flow regimes, comes different levels of phase interaction.

    So, pick a suitable model, or models, predict the flow regime & determine the appropriate properties.

    I have a few very useful references to hand. If you pm me, with your current e-mail address, I'll get these onto you.
    Engineering Specialist - Cuprobraze, Nocolok, CD Technology
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Chillerman, Mad is right and the whole question is just about how to get the properties of the split streams. If I read the previous posts correctly it seems it should be possible to simply move the 2 streams to their respective lines on the bubble but does that meet the no work and no heat input criteria is met. So I propose this:- (which is way too complicated for a Sunday morning I should add)

    As no work or heat has been applied to either of the separated streams we can write the state function as

    dS=dQ-dW

    and the process as dh=dQ-dW+pdv+vdp

    As dQ the heat input is zero and dW the work done is zero the dS must be zero

    So x*S4-S3+S5-x*S5 = 0

    And as both p the pressure and v the volume are constant dh can be set to zero so there is no gain or loss of enthalpy

    So m*(h4-h3)-m*(1-x)*(h4-h5) = 0

    Where h3 is the enthalpy at a quality of x
    And h4 is the enthalpy at the gas line
    And h5 is the enthalpy at the liquid line
    Also S3, S4 and S5 are the entropy at the same locations.

    This boils down to the fact if these state functions are equal to zero then we can indeed split the gas out and position directly on the gas line whilst the liquid must then be plotted on the liquid line with the caveat that both streams must have their respective masses carried with them and new processes can then be started.

    But I am still mystified why the gas can have its entropy changed without work or heat input?

    Chef

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by desA View Post
    The methodology for solution will very much depend on the two-phase model you select. Flow regime for two-phase flow can be rather interesting & the theory is far from settled.

    With different flow regimes, comes different levels of phase interaction.

    So, pick a suitable model, or models, predict the flow regime & determine the appropriate properties.

    I have a few very useful references to hand. If you pm me, with your current e-mail address, I'll get these onto you.
    Thanks for the offer of the 2 phase papers but we really need to get to the pure gas and liquid states and the 2 phase episode is already past. There seems to be very little referance to this problem where ever I have looked.

    Chef

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by Chef View Post
    Chillerman, Mad is right and the whole question is just about how to get the properties of the split streams. If I read the previous posts correctly it seems it should be possible to simply move the 2 streams to their respective lines on the bubble but does that meet the no work and no heat input criteria is met. So I propose this:- (which is way too complicated for a Sunday morning I should add)

    As no work or heat has been applied to either of the separated streams we can write the state function as

    dS=dQ-dW

    and the process as dh=dQ-dW+pdv+vdp

    As dQ the heat input is zero and dW the work done is zero the dS must be zero

    So x*S4-S3+S5-x*S5 = 0

    And as both p the pressure and v the volume are constant dh can be set to zero so there is no gain or loss of enthalpy

    So m*(h4-h3)-m*(1-x)*(h4-h5) = 0

    Where h3 is the enthalpy at a quality of x
    And h4 is the enthalpy at the gas line
    And h5 is the enthalpy at the liquid line
    Also S3, S4 and S5 are the entropy at the same locations.

    This boils down to the fact if these state functions are equal to zero then we can indeed split the gas out and position directly on the gas line whilst the liquid must then be plotted on the liquid line with the caveat that both streams must have their respective masses carried with them and new processes can then be started.

    But I am still mystified why the gas can have its entropy changed without work or heat input?

    Chef
    Afternoon Chef

    Thanks for such a detailed answer to work with,

    (This is going to take me all day to get my head around as I have to reference all the letter symbols first, before i can attempt to work out what you mean.)

    Morning MF

    But I will, you's have me hooked now.

    side tracking slightly away from the original reason for posting as i always look at the final acheivement

    the research that you's are doing is for the design of 'A'

    the problem i have is where they (liquid/vapour) end up and thus system balanceing

    the component that does the system work has a limited ability

    with this in mind

    the more work it does removing the vapour from 'A'

    the less work it can do in the usual way

    ideally the liquid will be subcooled before it leaves 'A' moving it away from the bell

    but it appears to me that this will reduce overall system ability to cool

    and there is a fine line of how much vapour can be removed from 'A' without this reduction

    I know you's must have already considered this so,

    Just asking, can enough vapour be removed from the liquid to increase cooling without loosing cooling ability in the conventional way ?
    Last edited by chillerman2006; 21-08-2011 at 02:38 AM. Reason: time lines
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Chef is in Fiji (Lucky bar stewerd), would I be working on refrigeration fomulures, or sucking dowm a Pina Colarda?
    Good on chef for making the wrong choice.
    CM, this not the process only the very beginning

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post
    Chef is in Fiji (Lucky bar stewerd), would I be working on refrigeration fomulures, or sucking dowm a Pina Colarda?
    Good on chef for making the wrong choice.
    CM, this not the process only the very beginning
    Bar Steward,

    When your hooked on info/solutions - yes the right choice!

    All I could think of last night during dinner - when most would be thinking of serviceing
    Oh well I will have to wait until your in a position to safely reveal

    Am even more entreagued now - as i was thinking it could only be in one position on a conventional system, obviously much more to it,

    Hope it all goes well next month
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Your were right Mad and so we went to the sun deck and had a couple of Fiji Golds and the watched the world cup final and saw Brazil win 3 - 2. Exemplorary. Good input.

    So the last test seems to be that h5-h3-x(h5+h4)+2xh3 must tend to zero to make

    dh=d(S+pv) true.

    But for this to happen it makes it an isochoric process and that then means that the gas portion at the outlet of the TXV already has the properties of the gas at the gas line. It is therefore only the liquid that holds the core thermodynamic properties. ie it does not matter what you do with the gas as it cannot affect the liquid except for normalising the mass if one removes it. Interesting!

    How to calculate this on the fly and use it is a distant goal at the moment. But without it how can we go to stage 2.

    Knickers, we are going back to the sun deck for some more Fiji Gold.

    Chef

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    World cup???? Brazil???? Soccer???? (surely not that far behind the times????????)
    Golds! yummmmmmmmmmmmm!
    So it would seem that all we need to know at this point, is the % by mass of the lquid and vapour streams at the relevent saturation points?

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    Thanks Mad


    I understand what you mean at last

    Talk about - I beat around every bush first & need spoon feeding

    Thanks Chef, if you had not have posted that question, there would still be that gap in my knowledge


    (But scrolling back up - no-one else came along and attempted it did they)

    Back on track

    So what you's were looking for was not me butting in, but someone on par with yourselves, who maybe could have come up with that something else that may or may not be there ?
    Have to chime in here, potential rant warning, and don't take it personally, but owning up to the fact that i've had to fight for every advancement in knowledge gained to date to succeed, not only in the refrigeration industry, as my main focus, but in my other curricular studies or hobbies i call them, including psychology and non mainstream medical advancements, that i struggle to digest the "quantum" aspect of this thread.. So continue, (giving the Jedi hand movement), and i will follow this thread through without asking questions and absorb what i can as it does trigger curiosity. Thanks "Mad" and C.M... Mike.
    To the optimist, the glass is half full. To the pessimist, the glass is half empty.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Annular flow, slug flow, plug flow - all have vapour split from liquid. Take your pick.

    You will need to understand the flow regime at some point, I fear. Thermodynamics will have assumptions about the fluid under consideration. Your final system will be somewhere between two extreme positions, due to liquid-vapour interaction.
    Engineering Specialist - Cuprobraze, Nocolok, CD Technology
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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mikeref View Post
    Have to chime in here, potential rant warning, and don't take it personally, but owning up to the fact that i've had to fight for every advancement in knowledge gained to date to succeed, not only in the refrigeration industry, as my main focus, but in my other curricular studies or hobbies i call them, including psychology and non mainstream medical advancements, that i struggle to digest the "quantum" aspect of this thread.. So continue, (giving the Jedi hand movement), and i will follow this thread through without asking questions and absorb what i can as it does trigger curiosity. Thanks "Mad" and C.M... Mike.
    Good Evening Mike

    You'll notice I did no contribution here mate, Have just found more I want to learn & comments keep the post up there, which may lead to another view from someone at their level
    If the World did not Suck, We would all fall off !

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by mad fridgie View Post
    World cup???? Brazil???? Soccer???? (surely not that far behind the times????????)
    Golds! yummmmmmmmmmmmm!
    So it would seem that all we need to know at this point, is the % by mass of the lquid and vapour streams at the relevent saturation points?
    It is the under 20 world cup held in Columbia and was live today.

    I will work on the other stuff later.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by Chef View Post
    I will work on the other stuff later.
    Evening Chef

    @ nearly 7pm more work, on a sunday, you must be due a few drinks now !
    If the World did not Suck, We would all fall off !

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Hi Mike, please ask questions! As design engineers it is very easy to get an idea into our heads, and very difficult to remove. Hence the questions do seem to be vague, as we are looking for a different approach or answer. So please jump in as this can also help us re think our thoughts. What I am looking for is for proof that the widget will not work. or reversly that the widget may work.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Just noticed now this post. I thought if Chef's asking a question and scrolling down, Mad Fridgie replies to it, then I have to read ever comma of this thread because both of them will dig very deep in the Thermodynamic laws again. Which I will do right now...reading, not digging.
    It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by desA View Post
    Annular flow, slug flow, plug flow - all have vapour split from liquid. Take your pick.

    You will need to understand the flow regime at some point, I fear. Thermodynamics will have assumptions about the fluid under consideration. Your final system will be somewhere between two extreme positions, due to liquid-vapour interaction.
    Would the flow regime relate directly to the exit of the expansion valve and its effects reduce if the bell (liquid vapour seperator) is a reduced velocity and impegement type. (basically allowing the heavy liquid to fall to the bottom and the lighter vapour to rise to the top)

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    I am certainly not at the level chef, DesA or Peter, just a different level. I am always learning from these guys,(thank you), If you are unsure of what is being said. ask!, and no doubt we will try to answer in a different termonology.

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    Re: How to assign thermodynamic properties after splitting two phase into gas and liq

    Quote Originally Posted by chillerman2006 View Post
    Come on chef

    not many are like me & dont care what others think !

    am not at this level, not at design level even

    and do not see what benefit it is

    this could be here a while as 60+ views already & nobody has a clue
    This quote stands!!
    It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.

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