2005 Fiscal Year Final Research Report Summary
Development of a High Performance Arc-Heater Which Can Provide High Atomic Oxygen Density Flow
| Project/Area Number |
14350507
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Aerospace engineering
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
KOMURASAKI Kimiya The University of Tokyo, Graduate School of Frontier Sciences, Associate Professor, 大学院・新領域創成科学研究科, 助教授 (90242825)
|
|---|
| Project Period (FY) |
2002 – 2005
|
| Keywords | high-enthalpy flow / arc-heater / atomic oxygen / laser absorption spectroscopy |
|---|
| Research Abstract |
A zirconia-coated cathode was applied to our arc-heater to achieve a flow containing high number density of atomic oxygen. In addition, multi-pass cell type highly sensitive laser absorption spectroscopy system with an external cavity was developed to enhance its sensitivity by two to three orders.
1.Development of an arc-heater with a zirconia-coated zirconium cathode
The arc-heater with an oxygen injection port located at the center of cathode (a hollow cathode) showed high erosion rate at the cathode tip and could survive only for several minuets. Therefore, we tested a zirconia-coated zirconium cathode instead and the oxygen was supplied from the cathode base via premixed gas with argon. As a result, it could operate for more than 3 hours without serious erosion. Furthermore, almost perfect dissociation of the oxygen was achieved.
2.multi-pass cell type highly sensitive laser absorption spectroscopy system
To optically access relatively low temperature but high degree of dissociation flow by the laser absorption spectroscopy method, we tested the multi-pass type sensitivity enhancement method. Although, last year, we tried the intra-cavity method, mode-hopping during the laser frequency scanning occurred too often to have the meaningful line shape of the absorbers. Therefore, this year, we tested the cavity-enhanced method, resulting in the enhancement by 400 times.
|
