A heat pump is a sealed unit that contains the refrigerant within a constant volume. How does the compressor increase the pressure within the high-pressure compressor and condensation spaces? Does it do this by pumping refrigerant gas from the evaporator and into the high-pressure space? Is this...
The other day I read on a website that a lower evaporator airflow causes lower low pressure side saturation temperatures and higher delta T on an air-conditioner. Now I think I know why a lower evaporator airflow would cause a high delta T. If there is less air moving over the evaporator, the...
I am trying to model an evaporator which evaporates water to steam in Matlab/simulink. Are there any governing equations i need to know and follow when modelling the evaporator mathematically? Please let me know.
Homework Statement
A double effect forward feed evaporator is to concentrate a 12.5% solution of a certain chemical compound "YZ". The feed is to be at and is to be 120 F of such an amount as to contain 6250 "YZ" per hour. Saturated steam is available at 250 F (29.7 psi ). The accepted value of...
Homework Statement
Hello, I have a task to make a heat balance of the evaporator. To do this, I was told to carry a few smaller energy balances in different parts of the evaporator. One of the things I had to calculate was the heat generated during steam compression.
-steam is entering...
It appears very non intuitive to me seeing TS diagram of vapour compression system; Area under the curve increases. But how seriously how higher evaporator temperature will lead to higher refrigeration effect. Refrigeration effect means lower temperature.
Hi All.
Please can someone help?
I have a question regarding calculating heat load and required surface area for a single effect evaporator.
Details:
Solution Feed rate 1.1kg s-1
Solution feed concentration 8%, concentrated to 30%
Feed solution at 60 degrees Celsius with Specific Heat Capacity...
Homework Statement
Before, I started to evaporate my solvent (butanol) by using rotary evaporator, I greased the ground glass joint holding my flask and bump trapper. Subsequently, I secured my flask sample and the trapper with Keck clip . Is there any possibility that my sample may have been...
An unfortunate incident happened at our triple effect caustic evaporator (32w.t% to 51w.t%). The third effect (highlighted red) where major steam (~12-13bar depending on flowrate) assisted evaporation take place, here for some reason Ni tubes get severely collapsed, while the plant was offline...
Hi All,
Is there a list of thermodynamics equations regarding the chiller process from condenser, evaporator, compressor to the regulator.
Say I have chiller load at 90%, what set of equations could I use to determine the supply temperature of chill water and condenser supply temperature to...
Hi!
For our class project, we have to design a system that freezes an amount of water as quick as possible.
The refrigerant is R134a. The compressor is known.
I don't really know how to get started here. How do I choose the evaporator pressure and the superheating, and equally the condensor...
Hello - fundamental thermo question which is puzzling me...
It concerns a multiple effect evaporator with condenser. Hot vapour is water, cooling medium is water.
My question stems from the following:
When the flow of cooling water to the condenser is increased, the pressure in the condenser...
You can read just bold, or all for further info. :D
The COP for a single stage vapour compression refrigerator increases with an increase in evaporating temperature. I would like to to know how it is achieved in reality with the use of an internal heat exch. on the evaporator.
Can anyone...
In vapor compression refrigeration, I know how to calculate the work done by the compressor (enthalpy at outlet - enthalpy at inlet), but I am lost on how to calculate the work done by the evaporator, condenser, and the expansion valve.
For the evaporator and condenser, if I wish to have a...
Hi! I really want to know how evaporator is made. i mean it is impossible to made by casting process, but i also not sure. anyboby who involve in this industry can please help me
Hi guys,
I'm stuck on some thermodynamic calculations and I would really appreciate some help!
I'm trying to calculate the refrigerant temperature inside of an evaporator (two-phase lumped parameter model) based on the exit temperature of the evaporator and the pressure.
I've understood that...
I believe that when refrigerant in an air-conditioner's evaporator boils into gas, the pressure on the refrigerant goes down tremendously. I believe that the drop in pressure on the refrigerant when it becomes a gas causes the temperature of the refrigerant to drop. I believe this because I...
Homework Statement
I have attached a diagram, for this question, I am stuck on how to calculate the flow rate.
there is 70kg/h of feed going into the evaporator, of which 11% is solids, so that's 7.7kg/h of solids, and so 62.3kg/h of liquid in the feed.
so now how do I calculate the...
Hello,
Could someone please give me an explanation using the following equation?
I work this evaporator machine but in the operations manual there is this equation below.I would like to further my knowledge.
Equation for Evaporation
Q = U x A x DT
Q = Energy Transfer (W)
U = Heat...
Hey,
I am trying to determine the importantance and difference of fouling in sizing the evaporator and condenser in a Refrigeration cycle?
Thanks,
Alexisonsmith
Window-type Aircon
how to get this in an actual experiment?
is it just (mass flow rate of the refrigerant X specific heat X Change in temp of the refrigerant)
or (mass flow rate of the air passing thru the heat exchanger X specific heat X Change in temp of the air)
or (mass flow rate of the...