The application of a centrifugal compressor in an aircraft leads to a larger frontal area of the aircraft.

1. Explanation of a centrifugal compressor:
- A centrifugal compressor is a type of dynamic compressor that uses rotating impellers to compress air or gas.
- It operates by converting kinetic energy into pressure energy, thereby increasing the pressure and temperature of the air or gas.
- It is commonly used in aircraft engines to compress incoming air before it enters the combustion chamber.

2. Role of a centrifugal compressor in an aircraft engine:
- The main purpose of a centrifugal compressor in an aircraft engine is to increase the pressure and temperature of the incoming air.
- This compressed air is then mixed with fuel and ignited in the combustion chamber to generate thrust.
- The higher the pressure and temperature of the air, the more efficiently the combustion process occurs, resulting in greater engine power and thrust.

3. Impact on the aircraft frontal area:
- The application of a centrifugal compressor requires the installation of the compressor at the front of the engine.
- This placement increases the overall size and frontal area of the engine.
- As a result, the aircraft's frontal area also increases, as the engine is typically mounted on the aircraft's wings or fuselage.

4. Reasons for the larger frontal area:
- The centrifugal compressor's large size and shape necessitate additional space and structure to accommodate it.
- This leads to an increase in the overall size and shape of the engine, which in turn increases the aircraft's frontal area.
- The larger frontal area can have aerodynamic implications, such as increased drag and reduced overall aircraft performance.

In conclusion, the application of a centrifugal compressor in an aircraft engine leads to a larger frontal area of the aircraft. This is due to the size and placement of the centrifugal compressor, which necessitates additional space and structure, ultimately increasing the overall size and shape of the engine and, consequently, the aircraft's frontal area.