What is the working principle of engine supercharging?
2 Answers
The working principle of engine supercharging is: by increasing the air pressure in the intake manifold, overcoming the interference resistance of the valves, and increasing the fuel injection volume, the engine's working energy is enhanced. Mechanical supercharging mainly relies on belt drive, and the speed of the internal blades is completely synchronized with the engine speed. The output of a mechanically supercharged engine increases with the rise in engine speed. Engine supercharging refers to addressing the issue of low intake efficiency in naturally aspirated engines at high-speed ranges. It can be divided into: 1. Centrifugal supercharger; 2. Roots-type supercharger; 3. Screw-type supercharger.
Last time I helped my buddy modify his old V8 muscle car, I researched this. Simply put, a supercharger is essentially a blower directly driven by the engine crankshaft that forces air into the cylinders. When the engine runs, the belt spins those two big helical rotors inside the supercharger like crazy, compressing the air denser and denser. More oxygen molecules mean you can inject more fuel. Unlike turbos that wait for exhaust gases to spool up, superchargers deliver instant throttle response and that kick-in-the-back feeling. But the downside is obvious—it saps engine power to drive the blower, so fuel consumption goes up. When modifying, remember to upgrade to forged pistons; stock ones can't handle the high pressure. The tuning shop told me that the distinctive whine of a Roots-type supercharger comes from the rotors chewing through air—totally badass.
