Finding the Condensed amount of water from a changing Temperature Airmass

In summary, the conversation is about the topic of Psychrometrics, which is the study of the thermodynamic properties of air. The person is looking for information on how much water can be condensed from a certain dewpoint when it is sent to a lower temperature. They have the initial dewpoint and the temperature of the environment where the air is being sent, and are using a fan with specific air flow and pressure. The conversation also mentions the use of a Psychrometric Chart and Trane's app to calculate thermodynamic data. The specific question is how to find the amount of water vapor that is condensed out when the air is cooled. There is also mention of a potential stumbling point involving the measurement of humidity in "grains" of
  • #1
gooseman
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I'm currently trying to find how much water can be condensed from an airmass of a certain dewpoint if it is sent to a lower temperature. The water will be condensed over a period of time. I have the dewpoint of the initial air and the temperature of the environment where the moist air is being sent to. The air is being blown in by a fan with an Air Flow of 190 CFM and Air Pressure of 17.78. What I mainly want to know is how much water should be produced with an initial x dewpoint with x temperature of the volume that the air is being sent into. (I'm a high school student so I may not know a lot of variables presented)
 
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This is a mechanical engineering/thermodynamics topic called "Psychromertrics". It is the study of the thermodynamic properties of air. Please read the wiki for an intro:
https://en.wikipedia.org/wiki/Psychrometrics

There are lots of copies of the Psychrometric Chart online, but I like apps where you can plug-in the conditions and get the thermodynamic data. There are ones for cell phones, but Trane has a simple and easy to use one you can download here:
http://www.trane.com/commercial/nor...gn-and-analysis-tools/calculators-charts.html

There's a lot to the overall subject, but your specific question is fairly straightforward: the air before cooling contains a certain amount of water vapor and the air after cooling contains less. Subtract to find how much water vapor was condensed out. You need to know the temperature, relative humidity and mass or volumetric flow rate going in and you need to know the temperature going out and to recognize the air is saturated on the way out (100% RH). Give it a shot and let me know fi you get stuck.
[unless I'm misunderstanding and this is a mixing problem?]

...one place you'll likely stumble: a "grain" of humidity is 1/7,000th of a pound.
 
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  • #3
russ_watters said:
This is a mechanical engineering/thermodynamics topic called "Psychromertrics". It is the study of the thermodynamic properties of air. Please read the wiki for an intro:
https://en.wikipedia.org/wiki/Psychrometrics

There are lots of copies of the Psychrometric Chart online, but I like apps where you can plug-in the conditions and get the thermodynamic data. There are ones for cell phones, but Trane has a simple and easy to use one you can download here:
http://www.trane.com/commercial/nor...gn-and-analysis-tools/calculators-charts.html

There's a lot to the overall subject, but your specific question is fairly straightforward: the air before cooling contains a certain amount of water vapor and the air after cooling contains less. Subtract to find how much water vapor was condensed out. You need to know the temperature, relative humidity and mass or volumetric flow rate going in and you need to know the temperature going out and to recognize the air is saturated on the way out (100% RH). Give it a shot and let me know fi you get stuck.
[unless I'm misunderstanding and this is a mixing problem?]

...one place you'll likely stumble: a "grain" of humidity is 1/7,000th of a pound.

So I did use the chart to find out the amount of moisture that is fully being sent into the system, but not to find out how much of it is being condensed. I'm thinking along the lines of finding the heat transferred to the air to make it condense it then finding how much water is condensed over a period of time. This may be a bit complex.
 

Related to Finding the Condensed amount of water from a changing Temperature Airmass

1. How does temperature affect the amount of condensed water in an airmass?

The amount of condensed water in an airmass is directly affected by the temperature. As the temperature of the airmass decreases, the ability of the air to hold moisture decreases, resulting in more water vapor condensing into liquid form.

2. What is the relationship between temperature and the dew point in determining the amount of condensed water in an airmass?

The dew point is the temperature at which the air is saturated with water vapor and condensation begins. As the temperature of the airmass approaches the dew point, the amount of condensed water increases.

3. How can we measure the amount of condensed water in an airmass?

The amount of condensed water in an airmass can be measured using a hygrometer, which measures the humidity of the air. This can also be estimated using weather balloons and satellite imagery.

4. Is the amount of condensed water in an airmass constant or does it change over time?

The amount of condensed water in an airmass is not constant and can change over time. It is influenced by various factors such as temperature, humidity, and air pressure.

5. How does the condensed water in an airmass affect weather patterns?

The condensed water in an airmass plays a crucial role in the formation of weather patterns. As the water vapor condenses into liquid or ice form, it can lead to the formation of clouds, precipitation, and other weather events. Changes in the amount of condensed water can also impact the strength and movement of weather systems.

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