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An experimental evaluation of the reliability of the Zeuch's method was carried out. The following were derived: 1) cavitation limits the minimum back pressure available; 2) the injection rate measured by the Zeuch's method agrees with that by the W.Bosch's method; 3) the effect of dynamic pressure of the injected fuel jet has a negligible effect on the pressure sensor which is attached to the chamber wall; and 4) the high-frequency noise after the end of injection observed in the Zeuch's measurement can be effectively removed by either a low-pass filter or an inverse Fourier transform processing.

The flow behavior of rubber compounds inside a mold is very complicated including various phenomena such as heat transfer from the mold, wall slip and swell at the divergent cavity. A slit rheometer which can measure the flow behavior inside a mold during curing was developed. The rheometer has a window which enables the observation of the flow behavior directly under 50 MPa. The pressure loss gradient along the flow direction and shear viscosity were found to be independent on the degree of cure but wall slip was observed. The wall slip phenomena could not be explained by slip analysis, because plug flow occurred due to little effects of the poiseuille flow. The pressure behavior inside the slit could be well predicted by using the equation obtained by assuming stress relaxation of visoelastic fluid occurs without share along the wall. The stress relaxation phenomena were predicted by taking into account the short and log relaxation time.

One of the authors has proposed to use the decay rate of EHRR, the effective heat release rate, d2Q/dθ2 as an index for the rapid local combustion [1]. In this study, EHRR profiles and the cylinder gas pressure oscillations of the low and high speed knock are analyzed by using this index. A delayed rapid local combustion, such as an autoignition with small burned mass fraction can be detected. In the cases of the low speed knock, it has been agreed that a rapid local combustion is an autoignition. Although whether the cylinder gas oscillation is provoked by an auto ignition in a certain cycle or not is an irregular phenomenon, the auto ignition takes place in almost all of the cycles in the knocking condition. Mixture mass fraction burned by an auto ignition is large. A small auto ignition may induce a secondary auto ignition, in many cases, mass burned by the secondary auto ignition is extremely large.