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This work examines the characteristics of a methanol fueled porous media burner, the principles of which may be used as a basis for a practical radiant heat source for an on-board catalytic methanol reformer. The burner uses a conventional engine port fuel injector designed for methanol use. The spray from the injector was impinged upon the bottom of a stack of two or three pieces of ceramic foam. The ceramics were 2.5 cm thick, 10 cm in diameter and were enclosed in a quartz cylinder for visualization. The upstream ceramic acted as a flame holder and the surface of the downstream ceramic was the radiation source. The range of air and fuel flow rates over which stable combustion was possible was investigated. Fuel flow rates between 0.12 and 0.48 gm/s were examined. Overall equivalence ratios between 0.65 and 0.2 resulted in stable combustion.

Laser Doppler velocimetry was used to make cycle-resolved velocity and turbulence measurements under motoring and firing conditions in a ported homogeneous charge S.I. engine. The engine had a flat pancake chamber with a compression ratio of 7.5. In one study, the effect of the intake velocity on TDC turbulence intensity was measured at 600, 1200, and 1800 rpm with three different intake flow rates at each speed. The TDC swirl ratio ranged from 2 to 6. The TDC turbulence intensities were found to be relatively insensitive to the intake velocity, and tended to scale more strongly with engine speed. For the combustion measurements, the engine was operated at 600, 1200, and 2400 rpm on stoichiometric and lean propane-air mixtures. Velocity measurements were made in swirling and non-swirling flows at several spatial locations on the midplane of the clearance height. The TDC swirl ratio was about 4. The measurements were made ahead, through, and behind the flame.

Laser Doppler velocimetry has been used to make cycle-resolved velocity and turbulence measurements in a homogeneous-charge, spark-ignition engine. The engine had a ported intake and disc-shaped chamber with a compression ratio of 7.5 to 1. It was operated at a speed of 1200 rpm and with a TDC swirl number of 4. A stoichiometric propane-air mixture was used, and ignition was near the wall. Measurements of the tangential velocity component were made in both firing and non-firing cycles at nine spatial locations along a radius 180 degrees downstream of the spark. The radial velocity component was also measured at four of the locations. All measurements were made in the center of the clearance height. Tangential component measurements were made as close as 0.5mm from the cylinder wall, and the radial component was measured as close as 1.5mm from the wall.