Abstract: Dual oxygen sensors before and after the exhaust catalytic converter of a motor vehicle combined with a specialized algorithm to substantially continuously compare the real time electric output of the oxygen sensors and, in response to the comparison, output an indication of the activity of the catalyst and failure of the catalyst. The algorithm in substantially real time "monitors" the continuously changing oxygen content of the before and after catalyst exhaust stream and through a phase comparison or an integration process in the preferred embodiment makes the proper comparison for determination of catalyst acceptability or failure. With a microcomputer equipped motor vehicle the algorithm is suitable for on-board continuous monitoring of the exhaust catalyst for indication to the vehicle operator when catalyst failure occurs. Failure can be total catalyst failure or partial failure to a degree where Federal exhaust emissions regulations are no longer met.

Abstract: In a spark ignition or compression ignition four cycle internal combustion engine, an exhaust expansion chamber is sized to produce a reflected exhaust pressure wave timed to an auxiliary reopening of the exhaust valve after the intake valve has effectively closed. The reflected exhaust pressure wave causes the re-entry into the cylinder of a quantity of intake charge (which has previously been drawn into the expansion chamber) subsequent to the effective filling of the cylinder through the intake valve, the result being a boost in cylinder charge and pressure on the compression stroke of the piston. At engine design speed, the power output of the engine is substantially improved over the power output without the boost in cylinder charge and in compression stroke pressure. The particular exhaust expansion chambers and valve re-opening timing is adaptable to single and multiple cylinder four cycle engines.

Abstract: A gas turbine engine is described in which a compressor, combustor and turbine are arranged in series flow relationship. Pressurized air enters the combustion chamber with approximately the same swirl as imparted to it by the compressor rotor, through an annular inlet tangentially of and at the outer bounds of the combustion chamber which has a toroidal configuration. This creates a vortex which swirls annularly and in which combustion of fuel is maintained. Mixing action in this vortex is enhanced through the introduction of additional air through chutes formed in the combustion chamber liner. The hot gas stream is discharged from the combustion chamber through an exit also at the outer bounds and tangentially thereof. In one embodiment fuel is introduced by means of nozzles aligned with the discharge ends of the chutes. In another embodiment the combustion chamber inlet is in the form of a venturi passageway and fuel is introduced into the inlet air by ports at the venturi throat.