Gas turbine supercharger — general description (Opel Omega A)

The OPEL OMEGA diesel engine (since 9/88) is equipped with a turbocharger. In the turbocharger, both turbine wheels are located on the same shaft, but in independent housings. The turbine wheels are driven by exhaust gases. The wheels rotate the shaft at a speed of up to 120,000 rpm. Since the exhaust and intake wheels are on the same shaft, fresh air is pumped into the cylinders at a constant speed. In new, more powerful turbo engines, the compressed air also passes through a radiator, where it is compressed even more.

Due to the high volumetric efficiency, the increase in power in such engines is up to 100%. But the increase in power, among other factors, is affected by the boost pressure, which in passenger cars is between 0.4 and 0.8 bar. If the boost pressure exceeds the value set by the manufacturer, then in this case the bypass valve opens and the pressure decreases.

Along with engine power, the presence of a turbocharger also increases torque, which primarily has a beneficial effect on the smoothness of engine operation. The main thing is that the supercharger shaft rotates at an increased speed and provides significant volumetric efficiency. As a rule, in an engine running at 1800-2200 rpm, boost pressure is already in effect.

Unlike petrol engines, diesel engines do not require compression reduction due to supercharging, since the injected fuel is completely used up even at low revs.

The turbocharger is a part that must operate with high precision. Therefore, it is recommended that only a specialist repair it. As a rule, if the supercharger is damaged, it is replaced as a set.

(Text copied from a web portal: «www.OpelBook.ru»)