Laser-Doppler velocimetry measurements in a motored IC engine simulator

A measurement technique and experimental results are presented for mean velocity and velocity fluctuations in a motored, axisymmetric engine chamber simulation. Three valve configurations are considered: open orifice, open valve, and operating valve. Measurements of axial and tangential velocity components have been taken at various axial and radial positions for one compression ratio (7:1) and one rpm level (31). The measurements show that the intake stroke (in both two and four stroke operations) result in a recirculating flow with substantial turbulence generation even at the low rpm value. The four-stroke results in an axisymmetric design are novel and especially significant since the ability exists to make comparisons with theoretical, axisymmetric, turbulent results.