A hair dryer works by generating hot air to dry up hair strands. But how does the machine generate its heat? Well, to answer that question, first we need to know some of the primary components of a hair dryer.
The fan and the air inlets
A hair dryer has a little fan that resembles a water wheel, which uses electrical energy to generate a gust of air as it rotates. Besides, the fan has a tiny motor that draws electrical energy to power the fan. When the motor gets power, it rotates in a fast-spinning manner together with the fan.
As the fan spins with a centrifugal force, its blades draw air into the dryer through the tiny air inlets on the side of the dryer. To allow only air to pass through, there is a safety screen covering the holes. Air then moves down to the barrel of the dryer.
A standard hair dryer comes with airflow regulators, which allow the user to set the machine on a high or low airflow mode. The information regarding airflow regulation is often available on the manual that accompanies the machine from the shop.
Usually, you can accomplish a high or low airflow into the dryer by altering the amount of current that flows to the motor. For example, with a low power, the motor and fan will spin with less speed. That leads to less air entering the dryer. When you step up power, the motor and fan gain rapid motion and more air enters the dryer.
Modern designs of hair dryers not only deliver hot air, but also produce ions as charged particles. The idea behind the technology is to help hair dry faster, make it healthier, smoother, and shinier.
In addition to other components, a hair dryer has a heating element in the form of a coiled nichrome wire. The element is often wrapped with insulators such as mica boards. Nichrome wire is a product of two metals: nickel and chromium. It is a common alloy in most heating elements in many household heating appliances such as curling irons or toasters. Two features make nichrome wire an excellent producer of heat:
- It conducts no electricity. This quality enables the heating element to resist heat as current flows through it.
- It undergoes no oxidation even after heating. Other metals such as iron can rust quickly when subjected to the level of temperature in hair dryers.
The airflow the fan generates forces its way to the heating element based on the shape of the dryer casing. When air first enters the dryer barrel, it is cooler compared to the nichrome wire. Therefore, heat transfers from the heating element to the air. As the fan pushes the air through convection force, cooler air enters the dryer and the cycle continues. The temperature of the air coming out of the fan depends on various factors, one of which is the amount of power that goes to the heating element.