Heating element Electric heating sheet heater making basics

What is a heating element? How do electric heaters work? What types of products are there? What types of heating materials are there? An overview of the comprehensive basics of heating elements.

 

  1. What is a heating element?

A heating element is a material or device that converts electrical energy directly into heat or thermal energy through a principle called joule heating. Joule heating is a phenomenon in which a conductor generates heat due to the flow of electric current. When an electric current flows through the material, electrons or other charge carriers collide with the ions or atoms of the conductor, creating friction at the atomic scale. This friction then manifests itself as heat. Joule’s first law (Joule-Lenz law) is used to describe the heat generated by an electric current in a conductor. This is expressed as,

P = IV or P = I²R

According to these equations, the heat generated depends on the current, voltage, or resistance of the conductor material. In the design of the entire heating element, resistance is an important factor.

Joule heating is evident in all conductive materials of varying intensity, except for a special material called a superconductor. In general, for conductive materials, less heat is generated because charge carriers flow through easily; For materials with high resistance, more heat will be generated. Superconductors, on the other hand, allow current to flow without generating any heat. In general, heat from a conductor is classified as energy loss. The electrical energy used to drive power equipment generates unnecessary heat in the form of transmission losses and ultimately does not produce any useful work.

In a sense, the efficiency of the electric heating element is almost 100%, since all the energy supplied is converted to its intended form. The heating element not only conducts heat, but also transfers energy through light and radiation. However, this only applies to some ideal resistors. The material’s inherent capacitance and inductance convert electrical energy into electric and magnetic fields, respectively, resulting in slight losses. Considering the entire heater system, the loss comes from the heat dissipated from the process fluid or the heater itself to the external environment. Therefore, the system must be isolated to utilize all the heat generated.