Ice Coolers: How Do They Work Actually?
Ice coolers: we can’t do without them. How else would we ensure our food and drinks are cool and fresh when we go camping? We hardly remember what people did before the invention of ice coolers.
But have you ever wondered how they work? What makes them so effective?
Let’s find out
The Science Behind Ice Coolers
The basic idea behind ice coolers is to keep food and drink cold with the aid of ice which you pack in around the food and the bottles. But ice is vulnerable to the heat which can cause it to melt.
The ice cooler must, therefore, slow down the melting rate of ice as long as possible. It achieves this through insulation.
Heat is The Enemy
Ice melts when it absorbs heat from the surroundings. For instance, warm air that comes in when you open the cooler, or the heat from a bottle of soda which you forgot to put in a refrigerator before storing in the cooler.
Heat transfers by two methods: conduction and convection. Conduction is the movement of heat between two objects when they physically touch each other. For example, when a bottle of soda conducts its heat to the ice, thus melting it.
Convection is when heat moves through the air. The cooler insulates the ice by minimizing both conduction and convection.
How It Reduces Conduction
The interior of the cooler is built lined with insulator material which helps decrease the conduction rate. Insulators are poor conductors of heat. The most commonly used insulation material is Styrofoam.
Styrofoam contains 98% air and is popular with manufacturers of various products because of its light weight, buoyancy, and insulation properties.
The small packets of air retained within the material are the secret behind Styrofoam’s effectiveness as an insulator. You see, atmospheric gasses have low density, making them poor conductors. Plus, the small size of the bubbles within Styrofoam prevents convection currents from forming, further undermining heat transfer within the material.
The heat transfer that does occur through Styrofoam is extremely slow, and that’s why ice can maintain freezing temperatures within the cooler for hours.
How To Minimize Convection
As we noted, convection is when heat travels through the air. Insulation with Styrofoam can only prevent heat transfer through the material.
The best way to minimize convection is by ensuring the amount of air circulating within the cooler is minimal.
So avoid opening the cooler too frequently. Another hack would be packing the cooler up to the top, layering your food and drinks with ice. At the bottom would be the items you will need last; and on top, the items you will take out first. That will ensure less air travels to the bottom.
You should also pack in as much ice as you can, so as to decrease the surface area occupied by air.
There you have it. A science lesson on how your ice cooler operates. I hope this article has shed some light on what you should do to ensure the food in your cooler stays fresh and cool for longer.