Just a minor correction, in your slides and in tables you use, the Enthalpy and Entropy, should be labelled Specific enthalpy and Specific entropy. Sure, it is a sortcut, but still, it is nice to be more .... specific :) Distinction is useful when then anlyzing enthalpy and mass flow and work required. Also thanks god you are using metric units.
Love this channel and love Paul. Watched several videos on this channel on various topics and learned so much. Starting this series, however, I can't help but notice the way he pronounces the letter "h". It sounds like he's saying "Heych-VAC". So weird, haha.
Great video, thanks! Just a note - if its W or kW it is power, if it is in Jaules - then it is work. Since the evap, condens and compressors are in kW all should be power.
I think it is based on your facilities (how far your evap and condenser areas are). And then you compute the corresponding piping pressure losses to adjust your respectiv capacities.
hey Paul !! we love you all God bless You and Your TEAM . we are proud of you. .. Dear Paul i want to ask a Question that why we need such kind of calculations ? or after finding all these unknown parameter what will be our next step ???
I imagine these calculations are more important when designing commercial or industrial scale refrigeration where its not just an off the shelf condensor and evaporator. You'd need to be able to select or size individual components, estimate system performance, and get an idea of cost.
The best video I've seen so far. My question is: For other gas like propane, methane and Neon? Where should I look? Tank you, I will definitely watch your other videos
1:37 - This is a beautifully crafted video on the explanation of the refrigeration cycle using maths! I look forward to being able to work through your amazing excel workbook on my own. he only thing you got backwards here in this diagram is the metering device flashes the refrigerant into the bottom of the evaporator and boils back to a vapor out the top. (I am _not_ a troll. I just noticed the error.) Well done, Paul! I didn’t see a link to your excel workbook on the website or in this video. Can you point us to a link?
Fantastic video but there seems to be an error. The gas flow rate of 3kg/s is far to high for the picture in the video. Data sheets normally give this as kg/h. So I assume your data sheet said 180kg/h and you only converted to minutes instead of seconds, giving extreme kW values. The compressor looks more like a 1.3kW rather than an 82kW. (i.e. 82/60)
Thank you for this video. May i ask you? How is possible to calculate dimension (ID and lenght) of capillary tube? ..when I use very stron vent on condenser, how can I calculate its effect on the system?
Hey,, will you please guide how the lg compressor Dkt208mah which is producing 23100 btu is used in o general hot and cold model 2.5 ton.,which have a capacity of 28000 btu.. How these btu difference compensate cooling efficiency..
Id like to build a solar assisted heat pump to wam water and uses thermodynamic panels and butane as a refrigerant. What videos do you suggest i watch to calculate the pump power needed and size heat exchanger coil size.
Hello The Engineering Mindset, Do you have any video about calculating and designing for length and diameter of copper tube in a refrigeration system. Thanks you.
I implemented a simulation to modeling a close real life scenario however how can I add a function that simulate losses in the system either to any component to see the change in quality, enthalpy and entropy or a total loss function to watch for COP, performance of system among them ? thanks
Same question here... I am having a difficulty starting at the cooling load. I'm starting to wonder if I am going to use the average COP of ref systems to know the power of the compressor that I would be using.
How can the temperature at state 1 and state 4 be the same?(Even in an ideal scenario) The refrigerant after leaving the evaporator will absorb heat and there will be a rise in it's temperature.
Hey Paul, thanks a lot for all your videos they are very resourceful. Can you please make a video for the safety devices installed in the chiller as it is a necessary devices to save chiller. Thanks.
Hi Paul. Thank you so much for your videos. I'm learning a lot from your videos because I'm new at "cooling world". Do you want to make a video about "Pump Down Cycle" of a chiller? If you do, I would be grateful to you. Best regards...
If we have a cooling load then how do we start the design of the Refrigerator? Also, how to fix the evaporator pressure if we are designing a system to cool at around -70 to -80 degrees celcius? Thank You!!
Hello , those video are great, i've learn alots of intresthing things. Can u do a video about refrigertant quantity For example : i have a condensing unit X and one evaporator N length of pipes please .
hey paul i have watched your all videos thanks for the great knowledge man. can u suggest me any book so that i can understand steb by step about hvac and get more knowledge
Hi Paul, when moving from stage 4 to stage 1 we assume the same temperature. But how do we account for superheat on the evaporator please? Would that be the “non idea” cycle? And if so is there a resource for this calculation anywhere please? Or is this accounted for in the suction and discharge input valves for the chosen compressor (ie 10k SH 5k SC)? Thanks
Hello, I'm looking to design my own small scale refrigeration system for educational purposes, and was wondering if there is a specific type of compressor recommended? Thanks!
i have one dryer air.. works 3 to 40 c temp i change filter and capillary tube but i haft to resize it... so now i have -7.5c entry to evaporator and exit 2.5c after to the accumulator i have - 3.5 and entry to compressor 9c is that normal.... how much must be the Δτ to the evaporator? and with the temp room so the dryer ro works good?? thanks
Line ( dome line) represents saturated liquid or saturated vapor? and everything within the dome is also saturated liquid or saturated vapor? And Left & right of the dome is sub cooled liquid and super heated vapor respectively? Please verify? Thank u
I want to build a deep freezer from scratch, what kind of expansion valve do I need using your calculation? Like what should I look for in data charts of expansion valve after doing calculations?
This might be not so smart question, but may I know what chemical modelling is usually used for the saturation table? What I mean, is it Peng-Robinson, or etc.?
Well a plate heat exchanger is just a compact heat exchanger where two fluids exchange thermal energy. The condenser and evaporator are the two points of heat transfer in the a/c system so you'll often find phx on these parts.
Is it possible that the exit of the evaporator (1), is further than saturation line (x=1)? I.e. I understand it would create pressure extra at 1, higher than at 4, but is it possible in practice (with sufficiently thin pipes or something?) I also heard of some systems that operate above the critical pressure, could you cover these systems in separate video?
Thank you for this useful video, I thoroughly enjoyed watching it. There is a one thing though: on the evaporator load: it's written as m*(h1-h4) but calculated as m*(h1-h3). I presume is the latter. Am I correct?
It is not isentropic. You probably meant isenthalpic, but it is not either of them. In reality, to be more precise it should be said that the enthalpy at 3 is the same as the enthalpy at 4. Between 3 and 4, enthalpy may be slightly varying. Hope it helps.
I want to ask something. I am repairing refrigerators for some time now, but I didn't solve this problem I encounter sometimes. After I recoil the evaporator of the refrigerator, I test the unit and it works fine, the pressure on both sides are normal. after 5-15 minutes the pressure in the low side begins to drop to negative and also in the high side lower to about 120 psi. I turn it off and the pressures take some time to normalize. Sometime, I just change the filter drier to solve the problem, but sometimes the problem continues even I change the filter drier. what causes the pressure to drop?
Hi, I want to rebuild a 120 L refrigerator into something else. I need to change both the evaporator and condenser with copper pipes that are much more compact. I suppose that with the condenser is easy - I need to measure the length and the diameter of the original condenser and coil another one, just more dense and to compensate the worsened airflow with a fan. But what about the evaporator? The fabric evaporators are aluminum plates with unknown tube diameter and sometimes there are even splits in the line (i don't know for what purpose). And I don't want to cool air, but a volume of water down to 2-4 degrees. Will this change the refrigeration cycle somehow? Thanks!
Sir, I think according to consumer cooling load we select the evaporator to reject the heat load developed by system, in that video evaporator rejected heat load is around 408kw and compressor needs 85kw(work done on the compressor) to generate the that much capacity, what is refrigeration capacity of that compressor
Just wanted to ask, I am using a different table and chart that comes from a book, which has quite different values than yours. When I read the preface, it says the tables and chart are based on a 0 *C where values of hf = 200 kj/kg and Sf = 1 kj/kg K. Is there a correction that I should do to get the same values that you get if I use my book. Thank you.
I am using a software called computer aided thermodynamic tables and it shows hf = 200 kj/kg and Sf = 1 kj/kg K same with yours. The table does not match with software for U,H and S.
if something is going through a phase change it's temperature remains the same. As in the evaporator from liquid to vapor. This is also a rough calculation (ideal case)
how to design according to the application? For example I want to design 50 ltr water cooler which cools water from 20 degree Celsius to 10 degree Celsius.
Question: How do you know the pressure required for the low and high side? Is it just the pressures the compressor can generate and need for the suction side? Also, if that's given or you find out, how do you know the mass needed in your system just use the ideal gas law at that point? Anyone can answer, I'm just curious
Hi Artur, the system pressure is determined by the type of system you need. The high side pressure is relative to the location of the installation. If you are in Mexico, the high side pressure will be higher than if you are in Canada juste because the high side temperature needs to be higher than the outdoor temperature. The low side pressure is determined with the kind of product you need to refrigerate. If it's a freezer, you need to be lower temperature, therefore lower pressure. To determine the mass of the system, you need the piping size and the density of the fluid at each part of the system. This can be quite the task so we usually apoximate until the installation in complete and the technician can tell you what is the final mass the he put in the system.
@@felixstg1 Hi, I want to rebuild a 120 L refrigerator into something else. I need to change both the evaporator and condenser with copper pipes that are much more compact. I suppose that with the condenser is easy - I need to measure the length and the diameter of the original condenser and coil another one, just more dense and to compensate the worsened airflow with a fan. But what about the evaporator? The fabric evaporators are aluminum plates with unknown tube diameter and sometimes there are even splits in the line (i don't know for what purpose). And I don't want to cool air, but a volume of water down to 2-4 degrees. Will this change the refrigeration cycle somehow? Thanks!
I have a question please, In our country we get ambient temperatures that reach 55 centigrade and the air temperature over the asphalt can reach 60 and inside the car if you increase the fan speed you will not get any cold air in the cabin. We use R134A refrigerant in our ac system. I was wondering if the gas will not condensate at these ambient temperatures.. ? Can you help please. Thanks a lot.
I am using a software and it shows hf = 200 kj/kg , hg = 400kj/kg and Sf = 1 kj/kg K , Sg = 1.72 kj/kg. The table that you have does not match with software for U,H and S.
We can make industries but the citizens, politicians and bureaucrats are utterly corrupted in Bangladesh. So I don't dare to make and to run the business on it. Thanks from Bangladesh.
This is a bit too reduced to be useful. Stage 1 is not a saturated vapor. There is something called "superheat". Compressing into stage 2 also adds entropy. Stage 3 is not a saturated liquid at boiling temps. There is something called "subcooling". These simple 4 step diagrams don't cut it.
⚠️ *Found this video super useful?* Buy Paul a coffee to say thanks: ☕
PayPal: www.paypal.me/TheEngineerinMindset
I want more information
So much simpler and concise than all the other videos,Kudos Paul
⚠️Learn how *REFRIGERANT WORK* here: ua-cam.com/video/lMqoKLli0Y4/v-deo.html ⚠️
dear uploader, God bless u for helping engineers with such precious videos.
It’s been 40 years since I took thermodynamics....thanks for the tutorial.
Just a minor correction, in your slides and in tables you use, the Enthalpy and Entropy, should be labelled Specific enthalpy and Specific entropy. Sure, it is a sortcut, but still, it is nice to be more .... specific :) Distinction is useful when then anlyzing enthalpy and mass flow and work required. Also thanks god you are using metric units.
Do you know how to calculate length of tube required in Evoprator and condenser?
Love this channel and love Paul. Watched several videos on this channel on various topics and learned so much. Starting this series, however, I can't help but notice the way he pronounces the letter "h". It sounds like he's saying "Heych-VAC". So weird, haha.
So glad I found this channel.Thanks for the great work mate.
Great video, thanks! Just a note - if its W or kW it is power, if it is in Jaules - then it is work. Since the evap, condens and compressors are in kW all should be power.
Do you know how to calculate length of tube required in Evoprator and condenser?
good question
ever got the answer?
I think it is based on your facilities (how far your evap and condenser areas are). And then you compute the corresponding piping pressure losses to adjust your respectiv capacities.
There are charts online for this. Heatcraft is a good source.
Now, THIS is a lovely and very useful video. Great work!
the great teacher, best of the best
Paul, I am buying you a coffee after I get paid for my next gig. Thank you so much!
That would be much appreciated, thank you.
hey Paul !! we love you all God bless You and Your TEAM . we are proud of you.
.. Dear Paul i want to ask a Question that why we need such kind of calculations ? or after finding all these unknown parameter what will be our next step ???
I imagine these calculations are more important when designing commercial or industrial scale refrigeration where its not just an off the shelf condensor and evaporator. You'd need to be able to select or size individual components, estimate system performance, and get an idea of cost.
Very useful and in easy way explanation.
The best video I've seen so far. My question is: For other gas like propane, methane and Neon? Where should I look? Tank you, I will definitely watch your other videos
Scroll to the bottom of this page for data sheets on all refrigerants theengineeringmindset.com/refrigerant-properties/
1:37 - This is a beautifully crafted video on the explanation of the refrigeration cycle using maths! I look forward to being able to work through your amazing excel workbook on my own. he only thing you got backwards here in this diagram is the metering device flashes the refrigerant into the bottom of the evaporator and boils back to a vapor out the top. (I am _not_ a troll. I just noticed the error.)
Well done, Paul! I didn’t see a link to your excel workbook on the website or in this video. Can you point us to a link?
Ahhh...takes me back to Thermo except presented much better. Well done!
You should get into the refrigeration design industry
Thanks a mil for these videos
Man you are a legend .. thank you
Great video information ❤,
Please make a video tutorial how to read enthalpy diagram
Please make se video on R290 as propane. As it has no superheated vapour chart.so how to solve it.please help.
A lot of thanks... we are always with you!
Can you explain why the entropy does not change before and after the compressor. Thanks.
Fantastic video but there seems to be an error. The gas flow rate of 3kg/s is far to high for the picture in the video. Data sheets normally give this as kg/h. So I assume your data sheet said 180kg/h and you only converted to minutes instead of seconds, giving extreme kW values. The compressor looks more like a 1.3kW rather than an 82kW. (i.e. 82/60)
Thank you for this video. May i ask you? How is possible to calculate dimension (ID and lenght) of capillary tube? ..when I use very stron vent on condenser, how can I calculate its effect on the system?
Hey,, will you please guide how the lg compressor Dkt208mah which is producing 23100 btu is used in o general hot and cold model 2.5 ton.,which have a capacity of 28000 btu.. How these btu difference compensate cooling efficiency..
Id like to build a solar assisted heat pump to wam water and uses thermodynamic panels and butane as a refrigerant. What videos do you suggest i watch to calculate the pump power needed and size heat exchanger coil size.
Hello The Engineering Mindset, Do you have any video about calculating and designing for length and diameter of copper tube in a refrigeration system. Thanks you.
Do you have any videos on capillary tube systems
I implemented a simulation to modeling a close real life scenario however how can I add a function that simulate losses in the system either to any component to see the change in quality, enthalpy and entropy or a total loss function to watch for COP, performance of system among them ? thanks
On what basis have you selected the compressor?
Hi! Thanks your sharing your knowledge! Can you tell how can I calculate the amount of refrigerate? Regards!
thank u so much for ur efforts but can u please upload how to calculate refregiation system using out and TEC peltier with water cooled system
Sir...can you elaborate the how you have taken the pressure for compressor from the manufacturer and along with it mass for the compressor also.
Very well explained. Video is good but sound is low.
Thanks Paul! At minute 4:42, what path would you have taken if you had started knowing the cooling load you are looking for?
Same question here... I am having a difficulty starting at the cooling load. I'm starting to wonder if I am going to use the average COP of ref systems to know the power of the compressor that I would be using.
hi fried very good explanation. can you calculate comperessor electrical power?
How can the temperature at state 1 and state 4 be the same?(Even in an ideal scenario)
The refrigerant after leaving the evaporator will absorb heat and there will be a rise in it's temperature.
Hey Paul, thanks a lot for all your videos they are very resourceful. Can you please make a video for the safety devices installed in the chiller as it is a necessary devices to save chiller.
Thanks.
nice content, Thanks!
good video
I hope you keep update :)
Hi Paul. Thank you so much for your videos. I'm learning a lot from your videos because I'm new at "cooling world". Do you want to make a video about "Pump Down Cycle" of a chiller? If you do, I would be grateful to you. Best regards...
thanks for your video and useful information . how can we design a refrigeration system according to the heat that we want to rejected from building??
If we have a cooling load then how do we start the design of the Refrigerator? Also, how to fix the evaporator pressure if we are designing a system to cool at around -70 to -80 degrees celcius?
Thank You!!
Hello , those video are great, i've learn alots of intresthing things. Can u do a video about refrigertant quantity For example : i have a condensing unit X and one evaporator N length of pipes please .
Is there a book that you could recommend?
Where did you get that 50.9 temp..? Pls explaine
hey paul i have watched your all videos thanks for the great knowledge man.
can u suggest me any book so that i can understand steb by step about hvac and get more knowledge
CIBSE guides are very good, try these
Hi Paul, when moving from stage 4 to stage 1 we assume the same temperature. But how do we account for superheat on the evaporator please?
Would that be the “non idea” cycle? And if so is there a resource for this calculation anywhere please?
Or is this accounted for in the suction and discharge input valves for the chosen compressor (ie 10k SH 5k SC)?
Thanks
I'd say use the danfoss coolselector 2 app, it's free and will do all the calculations for you. I even narrated the tutorial videos for them.
9:45 *Enthalpy and Temperature
thank you bro... this really helped...
Really helpful video. What effect would a superheating and subcooling heat exchanger have?
Excelentes videos, gracias
p=1200 kpa 2nd stage how you have choosed please explain thank you
Hello, I'm looking to design my own small scale refrigeration system for educational purposes, and was wondering if there is a specific type of compressor recommended? Thanks!
I'recommen recycling a compressor from an old fridge/freezer/whatever as it's the cheapest if you want to work at those temps.
If i know how much cooling capacity i need. How do i start this calculation process? Thanks
How would be the design of system, but 2 independent evaporator?
thanks for you
How can I do heat balancing of water cooled condenser?
Choice of refregeriant is 134A
Can someone help me out with entropy ? What is it and what does it mean when it’s increasing and decreasing in the refrigerant cycle.
Thanks
i have one dryer air..
works 3 to 40 c temp
i change filter and capillary tube but i haft to resize it...
so now i have
-7.5c entry to evaporator and exit 2.5c
after to the accumulator i have - 3.5 and entry to compressor 9c is that normal.... how much must be the Δτ to the evaporator? and with the temp room so the dryer ro works good??
thanks
Line ( dome line) represents saturated liquid or saturated vapor?
and
everything within the dome is also saturated liquid or saturated vapor?
And
Left & right of the dome is sub cooled liquid and super heated vapor respectively?
Please verify?
Thank u
awesome sir
I want to build a deep freezer from scratch, what kind of expansion valve do I need using your calculation? Like what should I look for in data charts of expansion valve after doing calculations?
Use coolselector by Danfoss. It'll do it all and the components
@@EngineeringMindset thank you. Is there any other kind of calculator or rule book for generic compressors and expansion valves?
Hello, I want to make 3kw and 3.5 kw evaporators and condensers, but I can't find the formulas. Can you help me please.
This might be not so smart question, but may I know what chemical modelling is usually used for the saturation table? What I mean, is it Peng-Robinson, or etc.?
137/5000
Hello Paul. Your videos are great. I'm just curious to know in which part of the system is located the plate heat exchanger? Thank you.
Well a plate heat exchanger is just a compact heat exchanger where two fluids exchange thermal energy. The condenser and evaporator are the two points of heat transfer in the a/c system so you'll often find phx on these parts.
Is it possible that the exit of the evaporator (1), is further than saturation line (x=1)? I.e. I understand it would create pressure extra at 1, higher than at 4, but is it possible in practice (with sufficiently thin pipes or something?)
I also heard of some systems that operate above the critical pressure, could you cover these systems in separate video?
Thank you for this useful video, I thoroughly enjoyed watching it. There is a one thing though: on the evaporator load: it's written as m*(h1-h4) but calculated as m*(h1-h3). I presume is the latter. Am I correct?
H3 = H4 isentropic process
It is not isentropic. You probably meant isenthalpic, but it is not either of them. In reality, to be more precise it should be said that the enthalpy at 3 is the same as the enthalpy at 4. Between 3 and 4, enthalpy may be slightly varying. Hope it helps.
Sir, how to Design condenser ?
Hi Paul, i am interested on condenser. I want to know how to calculate cooling capacity in watts or kw on a condenser?
Himo Rexhepi it's explained in the video, don't skip through.
The Engineering Mindset Thank you for replay, i am going to watch again the video. Have a nice day.
I want to ask something. I am repairing refrigerators for some time now, but I didn't solve this problem I encounter sometimes. After I recoil the evaporator of the refrigerator, I test the unit and it works fine, the pressure on both sides are normal. after 5-15 minutes the pressure in the low side begins to drop to negative and also in the high side lower to about 120 psi. I turn it off and the pressures take some time to normalize. Sometime, I just change the filter drier to solve the problem, but sometimes the problem continues even I change the filter drier. what causes the pressure to drop?
Hi, I want to rebuild a 120 L refrigerator into something else. I need to change both the evaporator and condenser with copper pipes that are much more compact. I suppose that with the condenser is easy - I need to measure the length and the diameter of the original condenser and coil another one, just more dense and to compensate the worsened airflow with a fan. But what about the evaporator? The fabric evaporators are aluminum plates with unknown tube diameter and sometimes there are even splits in the line (i don't know for what purpose). And I don't want to cool air, but a volume of water down to 2-4 degrees. Will this change the refrigeration cycle somehow? Thanks!
Sir, I think according to consumer cooling load we select the evaporator to reject the heat load developed by system, in that video evaporator rejected heat load is around 408kw and compressor needs 85kw(work done on the compressor) to generate the that much capacity, what is refrigeration capacity of that compressor
Just wanted to ask, I am using a different table and chart that comes from a book, which has quite different values than yours. When I read the preface, it says the tables and chart are based on a 0 *C where values of hf = 200 kj/kg and Sf = 1 kj/kg K. Is there a correction that I should do to get the same values that you get if I use my book. Thank you.
There is no need for correction as you calculate with differences most of the time. It the difference between 2 points that matters.
I am using a software called computer aided thermodynamic tables and it shows hf = 200 kj/kg and Sf = 1 kj/kg K same with yours. The table does not match with software for U,H and S.
Where is the Capillary Tube sizing video?
How to know the amount of mass m
bravo
12:30 How can the temperature at state 4 (refrigerant entering the evaporator) equal temperature at state 1 (refrigerant exiting the evaporator)?
if something is going through a phase change it's temperature remains the same. As in the evaporator from liquid to vapor. This is also a rough calculation (ideal case)
how to design according to the application?
For example I want to design 50 ltr water cooler which cools water from 20 degree Celsius to 10 degree Celsius.
reverse the equations
Can I have the excel file for this?
can i get compressor specifications of 1.5 ton for R134a
Sure watch this ua-cam.com/video/gKc1EwO6VeE/v-deo.html
Hey man, can we find cooling capacity in kw by enthalpy or entropy?
Can i have that excel sheet?
compressor on the video shows m: 3kg/s and not 7kg/s as you mentioned. I can't find any compressor that show's its mass flow rate specifications.
how can i design a refrigeration system for 10 degree output temperature and one tr
Just reverse the calculations shown and iterate
Question: How do you know the pressure required for the low and high side? Is it just the pressures the compressor can generate and need for the suction side?
Also, if that's given or you find out, how do you know the mass needed in your system just use the ideal gas law at that point?
Anyone can answer, I'm just curious
Hi Artur, the system pressure is determined by the type of system you need. The high side pressure is relative to the location of the installation. If you are in Mexico, the high side pressure will be higher than if you are in Canada juste because the high side temperature needs to be higher than the outdoor temperature. The low side pressure is determined with the kind of product you need to refrigerate. If it's a freezer, you need to be lower temperature, therefore lower pressure. To determine the mass of the system, you need the piping size and the density of the fluid at each part of the system. This can be quite the task so we usually apoximate until the installation in complete and the technician can tell you what is the final mass the he put in the system.
@@felixstg1 Hi, I want to rebuild a 120 L refrigerator into something else. I need to change both the evaporator and condenser with copper pipes that are much more compact. I suppose that with the condenser is easy - I need to measure the length and the diameter of the original condenser and coil another one, just more dense and to compensate the worsened airflow with a fan. But what about the evaporator? The fabric evaporators are aluminum plates with unknown tube diameter and sometimes there are even splits in the line (i don't know for what purpose). And I don't want to cool air, but a volume of water down to 2-4 degrees. Will this change the refrigeration cycle somehow? Thanks!
Why so low subcooling?
Subcooling is love subcooling is life...
KINDLY UPDATE WITH SCREW,SCROLL & RECIPROCATING AIR COMPRESSOR
Here you go! ua-cam.com/video/gYcNDT1d30k/v-deo.html
You say 7 kg/S but you put 3kg/S which is correct? Pls reply
❤❤
good Boy
I have a question please,
In our country we get ambient temperatures that reach 55 centigrade and the air temperature over the asphalt can reach 60 and inside the car if you increase the fan speed you will not get any cold air in the cabin. We use R134A refrigerant in our ac system. I was wondering if the gas will not condensate at these ambient temperatures.. ? Can you help please.
Thanks a lot.
I am using a software and it shows hf = 200 kj/kg , hg = 400kj/kg and Sf = 1 kj/kg K , Sg = 1.72 kj/kg. The table that you have does not match with software for U,H and S.
Also please also use US standard units for us yanks. Thanks.
We can make industries but the citizens, politicians and bureaucrats are utterly corrupted in Bangladesh. So I don't dare to make and to run the business on it. Thanks from Bangladesh.
This is a bit too reduced to be useful. Stage 1 is not a saturated vapor. There is something called "superheat". Compressing into stage 2 also adds entropy. Stage 3 is not a saturated liquid at boiling temps. There is something called "subcooling".
These simple 4 step diagrams don't cut it.
🇱🇰 thanks
Who's here after watching Adam Savage's One Day Builds video? 😂🤷🏼♂️
your formula for cooling load in evaporator not match with your explanation