Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 13, 2020 - September 16, 2020
When designing axial- injection end-burning hybrid rocket (EBHR), it is essential to obtain the boundary between stabilized combustion mode and flame spreading mode. Oxidizer friction velocity has been used as an indicator of them. The threshold value has obtained in the case with PMMA fuel and O2 as a constant value and used when designing EBHR. Recently, however, N2O is said to be useful for oxidizer, so we have to research if we can use N2O for EBHR. In this study, we aim to obtain the threshold value of friction velocity with PMMA fuel and N2O as the oxidizer. We conducted some combustion experiments and explored the relationship between friction velocity, chamber pressure, and flame behavior. As a result, we observed pressure dependencies of the threshold value of friction velocity, which is different from the result of the O2 experiment. There are two possibilities why such a result arose, 1) difference of oxidizer chemical species, 2) development of boundary layer.
