# Solar radiation on a horizontal tank

• eclaisse
In summary, the tank is exposed to solar radiation, which causes a variation in liquid level. To avoid a lot of degassing during big heats, an insulator could be put around the tank.
eclaisse
Hello everyone, I'm looking to estimate the variation of degassing on a horizontal tank of VC (vinyl chloride) due to solar radiation.
The feed flow is continuous but the outlet is batch flow. So there is a lot of variation of liquid level in the tank (constant pressure).
To avoid a lot of degassing during big heats, I want to estimate if it is a good idea to put an insulator around the tank.

How can I include a insulating element in my calculation ?
For now, I just have the basic equation of energy balance (convection and solar radiation).

Thanks.

Let's see what you've done so far.

BvU
Welcome to PF.

What is your approximate latitude on Earth ?
Is the tank axis N-S or E-W ?

How much variation is there in ambient air temperature ?
What exactly do you mean by “big heats” ?

What is the maximum capacity of the tank ?

eclaisse
Thanks Baluncore.

Here is some information :
Approximate latitude : 51° (Belgium) and the tank axis is N-S with a diameter of 3m and a length of 10 meters.
I want to see the utility of insulating. During summer we have temperature around 30 degrees celsius.

I try to use the basic equation : Q = U*deltaT*A where U = 1/R = 1/hi + lambda/e + 1/he
Then I compare with the addition of 10 cm rockwool as isolation.
So finally I have Q= [T(outside)-T(inside)]*U*A and I can compare and see the difference between both situation.

I have some questions :
1) I use basic data for hi and he (0.17 et 0.04 m^2.K/W) => Is it ok ?
2) Can I include the solar radiation with this method ?
3) After that, Can I use Q=m*Hvap to estimate my degassing ?

PS : I will upload my calculation in few hours (it will be clearer...)

Last edited:
After some research, I do these calculations...
It looks okai. But I still need to include the effect of solar radiation...

Is the VC at ##\ \ +##14 ##^\circ##C ? or at ##\ \ -##14 ?

It is +14°C. It is a calculated value (saturation temperature) from data pressure (2.8bar)

BvU
Hello, I update my calcul if someone is interested.
I juste have two questions : My way to estimate my outside surface temperature seems okay ?
And I have a big problem to estimate an average convection coefficient for both situation : (h_out in my first calculation (1/h_out = 0.05 m2.K/W) and h_in in my second (1/h_in = 0.17 m2.K/W). These coefficients change a lot the final result and I am not sure about my values (I just use theoretical value find in literature...).

Thanks a lot.

#### Attachments

• 1606139565575.png
17.9 KB · Views: 228
The key to this is to look at a worst case scenario, using upper bounds to the inside and outside heat transfer coefficients. That way the calculation should be conservative, and give an upper bound to the evaporation rate. I think your value for the inside heat transfer coefficient looks low. I would use a much higher value, on the order 500. Your outside heat transfer coefficient looks reasonable. Considering that, in the actual situation, the insulation is going to dominate, I guess these values wouldn't matter much.

## 1. What is solar radiation on a horizontal tank?

Solar radiation on a horizontal tank refers to the amount of energy from the sun that is absorbed by the surface of a tank that is positioned horizontally.

## 2. Why is solar radiation on a horizontal tank important?

Solar radiation on a horizontal tank is important because it can affect the temperature of the tank and the contents inside, which can impact the efficiency and effectiveness of the tank's function.

## 3. How is solar radiation on a horizontal tank measured?

Solar radiation on a horizontal tank is typically measured using a pyranometer, which is a device that measures the amount of solar radiation that reaches a horizontal surface.

## 4. What factors can affect solar radiation on a horizontal tank?

The amount of solar radiation on a horizontal tank can be affected by factors such as the angle and orientation of the tank, the location and time of day, as well as weather conditions and cloud cover.

## 5. How can solar radiation on a horizontal tank be controlled?

Solar radiation on a horizontal tank can be controlled by using shading devices, such as awnings or trees, to reduce the amount of direct sunlight hitting the tank. Insulation can also be used to minimize heat absorption from solar radiation.

• Mechanical Engineering
Replies
3
Views
1K
• Sci-Fi Writing and World Building
Replies
21
Views
1K
• General Engineering
Replies
14
Views
2K
• Engineering and Comp Sci Homework Help
Replies
1
Views
1K
• DIY Projects
Replies
41
Views
8K
• Introductory Physics Homework Help
Replies
14
Views
3K
• General Engineering
Replies
2
Views
4K
• Thermodynamics
Replies
9
Views
9K
• Other Physics Topics
Replies
1
Views
2K
• General Engineering
Replies
13
Views
44K