Wednesday 9 March 2016

How to build the best camp-fire

No overnight expedition into the woods is complete without a roaring camp-fire to provide light and warmth to campers as night draws in. Seasoned outdoor men and women will have their own idea of the perfect camp-fire; this entry will look to science to find the best way to construct a camp-fire. To discover this we must begin by understanding the basics of fire and how it works.

Simply put, fire is just the visible part of a chemical reaction called combustion. This reaction requires three elements in order to for combustion to occur- Oxygen, heat and fuel.

This idea of the 'fire-triangle' as shown here not only provides a check-list for what is needed for combustion to take place, but also has the shows ways in which someone can put out a fire. Remove any one of these elements and the reaction won't be able to sustain itself and will die.




Understanding that combustion needs these elements in order to occur is key to building an efficient fire. But there are many ways of achieving this with differing efficiency.


This brilliant illustration details various methods of fire construction show that each model has its own advantages and distinct uses. However, this entry looks to science to answer the question: how can we build the best fire?




    J. A. Jones Distinguished Professor of Mechanical Engineering at Duke University, published research in 2015 stating that that in order to create an efficient fire that generates and radiates the highest heat, certain criteria must be met.

By using his widely accepted Constructional Law, Bejan has shown that in order for a fire to met its potential heat level, it must be constructed so that the height of the pile of fuel is the same as the base diameter diameter of the pile itself. The pile must allow oxygen to travel through it, ensuring that natural convection can provide the oxygen required to drive combustion.

The following graph released by Duke University vastly simplifies Brejan's findings.



So there you have it, the scientific argument for the best camp fire. The most effective method of testing Brejan's theory is to go out, test  and experience it yourself. Just ensure that you do so safely and follow the rules of sensible camp fire use which can be found here.




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