| Publication Date |
1982 |
| Personal Author |
Kisara, K.; Miyajima, H.; Abe, N.; Sato, M.; Kamata, M. |
| Page Count |
23 |
| Abstract |
The LE-5 engine, which will be installed in the second stage of Japan's next launch vehicle, requires tank head ignition of the main thrust chamber and allows a small pressure budget to the igniter. This experimental study was conducted to obtain information to improve the vacuum ignitability of the air-gap type torch igniter. Vacuum ignition tests of the modified igniters as well as the original igniter were conducted to obtain the minimum ignition pressure as a function of mixture ratio, i.e., lines of demarcation between the ignition and no-ignition regions in the preignition chamber pressure-mixture ratio plane. For the film cooled igniter, a marked reduction of the minimum ignition pressure was demonstrated by the combined effect of the following modifications: (1) locate the igniter throat just downstream of the film coolant injection ports, (2) reduce the throat diameter to half that of the original igniter, and (3) make 6 spikes on the otherwise circular cross section of the cathode, the spikes being in line with 6 fuel orifices. Test results of a dump cooled igniter, photographic observations of the electric discharge over the annular gap, a discussion of the possible mechanism of a ignition failure, and the effect of an inadvertent solid particle contamination on the ignitability are also described. |
| Keywords |
|
| Source Agency |
|
| NTIS Subject Category |
|
| Corporate Authors |
National Aerospace Lab., Tokyo (Japan).; National Aeronautics and Space Administration, Washington, DC. |
| Supplemental Notes |
In Japanese; English Summary. |
| Document Type |
Technical Report |
| NTIS Issue Number |
198314 |
