Which type of nozzle was the first used in turbine engines?

The simplex fuel nozzle was indeed the first type used in turbine engines. This design allows for a straightforward and efficient way to atomize fuel and introduce it into the combustion chamber, which is crucial for achieving optimal combustion efficiency in the engine.

In a simplex nozzle, there is a single fuel stream exiting the nozzle, which means it is simpler in design and less costly to manufacture. This made it a practical choice for early turbine engine designs, as engineers were focused on reliability and ease of maintenance. The simplex nozzle effectively atomizes the fuel using a single flow path, allowing for adequate mixing with air for combustion.

Over time, as technology progressed and the performance demands on turbine engines increased, more complex nozzle designs were developed, such as duplex and variable nozzles. These newer designs allow for better control of fuel delivery and atomization, catering to various operating conditions and improving fuel efficiency and performance. However, understanding the simplex nozzle's foundational role in the evolution of fuel metering in turbine engines is essential, as it set the stage for advancements in nozzle technology.