Well, you’ve made it past the cover page. That’s a good sign, and I hope that your curiosity will be rewarded in the following pages.
The physical concepts and phenomenon that enable the operation of thermosyphons can at times be complex-but don’t be scared. This tutorial will start with the most rudimentary explanation of thermosyphons, and proceed from there to deliver more in depth examinations in a step by step process. Let’s get right down to business.
The diagram below shows the steps in thermosyphon operation. STEP 1-Heat flows into the thermosyphon, STEP 2-Heat flows through the thermosyphon tube, and Step 3-Heat is released into the atmosphere
Simply stated, a thermosyphon is a device which moves heat from one place to another. There are different types of thermosyphons which are used for different applications, but for the purposes of this primer we will concentrate on thermosyphons used by the construction industry to stabilize frozen ground. For example, consider a road built over permafrost.. In this situation it is desirable to keep the ground from thawing, otherwise the road embankment will be destroyed. A thermosyphon “collects heat” from the frozen ground. This collected heat is brought to the top of the thermosyphon and the cooling fins, where it is released into the atmosphere. In this way, the ground remains frozen.
Now, the thought of frozen soil warming the atmosphere may be hard to grasp. This brings us to an important point about the thermosyphon- they only work when the ambient air temperature is below the temperature of the soil (less than 31 degrees Farenheight). With this in mind, we can consider thermosyphons from a different perspective; a thermosyphon increases the exposure of sub-surface soil to freezing temperatures. Another thought, although not totally correct from a physical standpoint, is that the thermosyphon brings cold into the soil.
Now that these basic concepts have been introduced, new questions arise. For instance, “How exactly does a thermosyphon transfer heat?” Let’s move on to the next page and take a look at what’s going on inside of the thermosyphon.
