What are Electrothermal Thrusters?

Electrothermal thrusters uses electric energy to heat the propellants either into a plasma or hot gas which is then expanded through a nozzle to produce thrust. Compared to both electromagnetic and electrostatic propulsion systems that propel charged ions through the use of electric and magnetic fields, electrothermal thruster relies upon thermal dynamics to propel the system.

Electrothermal thrusters make use of heaters to heat the propellant. As a result, this increases the pressure and expands the gas which forces the energized mass out of the nozzle of the thruster providing thrust to the spacecraft. There are several ways in which electric energy can be used to heat propellants. Based on this electrothermal thrusters can further be classified into two basic types:

• Resistojet Thrusters
• Arcjet Thrusters

Based on the concept of electrothermal propulsion there are advanced versions of electrothermal thruster which are being currently developed some of which are listed below:

• Microwave Electrothermal Thrusters
• Pulsed Electrothermal Thrusters