What role does the nozzle play in a magnetohydrodynamic generator?

In a magnetohydrodynamic (MHD) generator, the nozzle serves a critical role in the conversion of thermal energy into kinetic energy. It accelerates the hot, electrically conducting gas (or plasma) to extremely high velocities, typically ranging from 1,000 to 2,000 meters per second.1

By increasing the gas velocity before it enters the generator channel, the nozzle ensures the fluid reaches the necessary speed to interact effectively with the magnetic field. This high-velocity flow is essential because the power output of an MHD generator is proportional to the square of the gas velocity. Once accelerated, the gas is injected into the channel, where its kinetic energy is converted directly into electric energy as it moves through the applied magnetic field in accordance with Faraday’s law of induction.12