# Fill an empty bottle with R-134a

• stoky
In summary, the conversation discusses filling a bottle with R-134a from a fluid line. The bottle is initially empty and has a volume of 12 litres, and the filling process is adiabatic. The fluid line contains R-134a at 20 bar, saturated steam. Using the second equation of energy balance, it is determined that the final internal energy of the R-134a in the bottle is equal to the initial internal energy of the fluid in the line. This results in a final mass of 1.11 kg, specific volume of 0.01081 m^3/kg, and temperature of 83.18 degrees Celsius. There is some uncertainty about the correctness of the calculations due to unclear notation.
stoky

## Homework Statement

We want to fill a bottle with R-134a. The fluid comes from a fluid line.
1. The bottle is initially empty, the bottle volume is 12 litres, the bottle is insulated (adiabatic filling).
2. The fluid line contains R-134a at 20 bar, saturated steam.

## Homework Equations

Using the second equation of energy balance.

## The Attempt at a Solution

From the bottle perspective:
Qcv=0
Wcv=0
dEcv/dt=m•ui
me=0
hi=428.2 kJ/Kg

Then:
mi•ui=mi•hi
Then
ui=428.2 kJ/Kg
Which reading R134a tables results in superheated steam: P2=2000 kPa, u2=428.2 kJ/Kg.

Results in m2 (bottle)=1.11 Kg
Specific volume=0.01081 m^3/Kg
Temperature=83.18 celsius

My concern is if the calculations are correct.

#### Attachments

• 9vehcw.jpg
32.6 KB · Views: 655
stoky said:

## Homework Statement

We want to fill a bottle with R-134a. The fluid comes from a fluid line.
1. The bottle is initially empty, the bottle volume is 12 litres, the bottle is insulated (adiabatic filling).
2. The fluid line contains R-134a at 20 bar, saturated steam.

## Homework Equations

View attachment 235368
Using the second equation of energy balance.

## The Attempt at a Solution

From the bottle perspective:
Qcv=0
Wcv=0
dEcv/dt=m•ui
me=0
hi=428.2 kJ/Kg

Then:
mi•ui=mi•hi
Then
ui=428.2 kJ/Kg
Which reading R134a tables results in superheated steam: P2=2000 kPa, u2=428.2 kJ/Kg.

Results in m2 (bottle)=1.11 Kg
Specific volume=0.01081 m^3/Kg
Temperature=83.18 celsius

My concern is if the calculations are correct.
I'm not sure whether you did it right or not because your notation is all screwy. The differential equation should be
$$\frac{dE_{dv}}{dt}=\dot{m}_i h_i$$
so that $$u_{final}=h_i$$
If that's what you did, then it is correct.

## 1. What is R-134a and why is it used in bottles?

R-134a is a type of hydrofluorocarbon (HFC) refrigerant that is used in bottles as a cooling agent. It has a low boiling point and is non-toxic, making it safe for use in food and beverage containers.

## 2. How do I fill an empty bottle with R-134a?

Filling an empty bottle with R-134a requires a filling machine or a special valve that is designed to transfer the refrigerant into the bottle. The refrigerant is compressed and then released into the bottle, filling it with gas.

## 3. Where can I purchase R-134a to fill my empty bottle?

R-134a can be purchased at most hardware stores, automotive supply stores, and online retailers. It is important to make sure you are purchasing a high-quality, pure form of R-134a for best results.

## 4. Are there any safety precautions I should take when filling a bottle with R-134a?

Yes, it is important to wear protective gear such as gloves and goggles when handling R-134a. It is also important to properly ventilate the area where you are filling the bottle and to avoid inhaling the gas.

## 5. How long will the R-134a stay in the bottle before it needs to be refilled?

The length of time that R-134a will stay in the bottle depends on the size of the bottle and the amount of gas used. It is important to monitor the pressure inside the bottle and refill as needed to maintain proper cooling.

• Introductory Physics Homework Help
Replies
2
Views
3K
• Engineering and Comp Sci Homework Help
Replies
26
Views
6K
• Engineering and Comp Sci Homework Help
Replies
1
Views
2K
• Engineering and Comp Sci Homework Help
Replies
10
Views
4K
• Mechanical Engineering
Replies
1
Views
13K
• Biology and Chemistry Homework Help
Replies
2
Views
13K
• Mechanical Engineering
Replies
8
Views
5K