How the turbine works
Basic components of the OPRA Turbine OP 16:
- Reduction gearbox
- Shaft with bearings
- Combustion chamber
- Turbine and exhaust diffuser
A starter motor speeds up the rotor initially and directs the compressed air from the compressor into the combustion chamber where fuel is introduced and burned.
The heated air expands through the turbine which drives the connected compressor. The starter motor is disengaged and the engine accelerates on its own to the operating speed of 26.000 rpm.
Now the generator load is applied. The reduction gear brings down the engine speed to fit the generator speeds (1500 or 1800 rpm).
The closely coupled compressor and turbine is connected to the shaft / bearings structure.
After the gas has expanded through the turbine, the final expansion is provided by the exhaust diffuser, exiting at atmospheric pressure. The exhaust diffuser adds about 10% to the total output of the engine.
Following the expansion, the exhaust still contains a large amount of energy. In the case of the OP 16 engine, the exhaust temperature is about 560 Celsius. This is a good temperature to raise steam for industrial processes. This process is called CHP (Combined Heat and Power) and is an important means to reduce overall fuel consumption and thereby CO2 emissions.