Recent Experimental Efforts on High-Pressure Supercritical Injection for Liquid Rockets and Their Implications
Figure 24
Plot of the averaged dark-core length (a) and the root mean square (RMS) of the length variations (b) normalized by the inner diameter of a LN2/GN2 coaxial jets injector. The solid symbols and lines represent data when the acoustic driver is off, and the hollow symbols and dotted lines show results when the acoustic driver is operated at ~3 kHz. The diamond and square symbols are for sub- and near-critical chamber pressures, respectively. All cases are for the low nominal outer-jet temperature of ~140 K. In the inset, the words sub and near refer to subcritical and near-critical chamber pressures, respectively, and the words OFF and ON refer to the acoustic driver being off and on at ~3 kHz, respectively. Davis and Chehroudi [42, 43].
