pressure-wave supercharger the opened-up drum can be used to demonstrate the supercharging by sliding the gas column the gas-column slide is moved along a curved path, so that the actual flow conditions can be shown description ordernumber 416 see also: speed governor of a distributor-type injection pump centrifugal governor of a DE (idle- and maximum-speed control) solenoid valve of a radial-piston distributor pump downdraught carburetor