Physics of Light/Infrared for Solar Stills Research

[Greenybwa]

Hi,

I am doing my dissertation for Mechanical Engineering on Solar Stills and my mentor has suggested it would be a good idea to research the physics of light/infrared absorption, transmission, water evaporation and condensation. I am wondering if anyone has good book recommendations for me to look at so I can best understand the sciences to optimize my design.

I'm not too sure how in depth it would have to be but most of the links I've found are directed towards around GCSE level in the UK which I'm guessing is not enough information since after reading it all it just seems to be very surface level, but I don't want something so complex I can't understand it myself as an engineer.

Thanks a lot and I look forward to the replies.

 

[Phylosopher]

I don't have a book to suggest honestly. And, I don't have an idea on how much you know about these subjects to begin with, so I am not sure what to suggest! The physics ideas might be something you already know, or something totally knew to you.

For example, diagram phase might be interesting! Though, you might be totally unfamiliar with:

Or the fact that the sun spectrum diagram is not uniform. This also means that you can harness more or less energy depending on the domain of light you are interested in:

Are these familiar things to you? or are they new?
- If they aren't familiar, start from these subjects and you will find good sources. If you are familiar with them and don't find them helpful, you might want to specify a bit.

 

[Tom.G]

For test result comparison of various coatings see:

"SOLAR ABSORPTION CHARACTERISTICS OF SEVERAL COATING AND SURFACE FINISHES"
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19770013623.pdf

Cheers,
Tom

 

[Greenybwa]

Thanks Tom.G that's a good link for me to add and use. I have seen similar information in other scientific papers I have been looking at.

In regards to Phylosopher, I have seen the phase diagrams in my class but I'm not sure how relevant that is for me so I'm guessing I need to brush up on phase diagrams. I don't see it being useful currently? What do you have in mind me using this for? The second image was a pretty good point for me to think about however I didn't know that it's not uniform so this gives me another route to look down thanks a lot!

EDIT: I will just specific my dissertation slightly. The solar still is to be designed for people in poor conditions with limited clean drinking water, such as Sub-Saharan Africa. So this means it should be designed with cheap and readily available materials and be able to supply water to a family of 6 individuals. For this reason I'm thinking it's not a feasible option for me to fine tune the glass to be the most efficient because if the glass breaks then they would be stuck and as a result the design is not fit for purpose.

So I'm thinking that going so into depth about the best and most expensive materials is not a good route and I was hoping more to get an informed idea about the physics so it can help me make a decision based on what materials might be available in Sub-Saharan Africa so when it does get damaged it is easily replaced.

I guess it would be more background knowledge about the whole process is what I am looking for but like I say I can't really seem to find a decent source for this. I've been reading lots of papers about how a solar still should be designed for efficiency for example, and also which materials would be the most efficient to absorb light and interestingly enough the use of bubble wrap to improve water yield but the actual physics behind it all I'm struggling to educate myself on. Sorry for the long edit but I thought it was needed.

Thanks

 

[Phylosopher]

The second image was a pretty good point for me to think about however I didn't know that it's not uniform so this gives me another route to look down thanks a lot!

I was not sure whether that would be helpful, I am happy it did give some ideas. I think discussing ideas is better than discussing what textbook to read at your position.

In regards to Phylosopher, I have seen the phase diagrams in my class but I'm not sure how relevant that is for me so I'm guessing I need to brush up on phase diagrams. I don't see it being useful currently? What do you have in mind me using this for?

Well, a still uses vapor. You can raise the temperature to/above 100 C for example, or you can lower/raise the boiling point by changing pressure.
This might be silly thing to do for an engineer, I don't know really. I am just a physicist, but I think it might be useful.

I guess it would be more background knowledge about the whole process is what I am looking for but like I say I can't really seem to find a decent source for this. I've been reading lots of papers about how a solar still should be designed for efficiency for example, and also which materials would be the most efficient to absorb light and interestingly enough the use of bubble wrap to improve water yield but the actual physics behind it all I'm struggling to educate myself on. Sorry for the long edit but I thought it was needed.

You may need a good undergraduate level textbook on thermal/statistical physics. I like "An Introduction to Thermal Physics" By Daniel V. Schroeder. It's not the best textbook for physicists, but it is light and very approachable.

EDIT 1: I heard a lot of my chemical engineering friends talk about water stills, they might have a take on what you are searching for.