Model light reflecting into a solar cooker?

About Truespace Archives

These pages are a copy of the official truespace forums prior to their removal somewhere around 2011.

They are retained here for archive purposes only.

Model light reflecting into a solar cooker? // Tech Forum

1  |  

Post by gaiatechnician // Dec 14, 2008, 8:20am

gaiatechnician
Total Posts: 1
Solar cooking is not much used here but it is used lots in India and in Africa it is seen as a very useful tool against deforestation. But design of solar cookers continues to be in the dark ages because it is essentially design for poor people and they cannot pay much.

In September I designed a new "compound" parabolic reflector for solar cookers. Before I made it, I asked about software to model the light going in but I got few suggestions back.

I ended up using slow on paper design with lots of doubt about where the light actually went and even so, I won a prize in an internet science competition for it.

It ended up with comparable results to a commercial sk14 solar cooker but only needs to be moved every couple of hours!

And if I do find suitable software, there are lots of amateur solar cooks interested!

The problem with the sun is that it moves! Many people ignore that movement and think that parabolic reflectors are best. So 15 minutes later your dish is out of focus and some of the light is already missing your cooking pot! In my case I could use the software to refine the compound parabolic dish and to design a new compound parabolic reflector for the tracking solar accumulator project. Other solar cooks might use it to make better reflectors for box ovens and cookits and other panel cookers and to better place their cooking vessels in these ovens.

So, I have been told that truespace models reflection well,

can it model the light from the sun moving across the sky too?

If it could do that for one day it would be great.

If it is capable of modeling the sun for an entire year that would be magnificent!

Anyway, how much of these tasks can truespace do?

Also if anyone is interested, would you like to model a parabolic and compound parabolic solar cooker over time?

Basically the "ball of light" produced by the compound parabolic dish is maintained for a long period of time while the point of light produced by the parabolic dish starts to degrade immediately. http://www.youtube.com/gaiatechnician is my utube videos where you can see more about the ideas.

Thank you for your time

Brian White

Victoria BC Canada

Thankyou for your time

Brian 'white

Post by TomG // Dec 15, 2008, 3:44am

TomG
Total Posts: 3397
You would need to use caustics to calculate reflected light. This takes a lot of processing power so would be slower to render than not using caustics.


You could write scripts to handle the sun position, and move lights following that formula, and then render to see how the light is focused. I imagine writing the scripts to calculate where to place the lights dependent on geospatial location, time of year and time of day would be quite tricky, as there is a lot to that, but I can see no reason why it couldn't be implemented in tS via scripts.


You could use the SDK and so code in C# instead, which may allow use of existing libraries that solve the sun calculation issue.


Note that doing an animation with caustics could be very slow, eg if you want to see your solar cooker's performance over a period of time, you'd have to render multiple frames and not just one image, and with caustics being processor intensive and so taking a while to render each single frame, then that would all add up of course.


To use caustics, you'd have to use either Virtualight or V-Ray to render with.


HTH!

Tom
Awportals.com is a privately held community resource website dedicated to Active Worlds.
Copyright (c) Mark Randall 2006 - 2021. All Rights Reserved.
Awportals.com   ·   ProLibraries Live   ·   Twitter   ·   LinkedIn