| In the course of developing the chemical oxygen iodine laser (COIL), people pay double attentions to the singlet oxygen generator (SOG) because it is a key part for COIL. The configuration and performance of SOG will affect the reaction efficiency, the excitation efficiency then the chemical efficiency of the laser. Hence, optimizing theparameters which reflect the performance of SOG is an important means to improve the configuration and performance of SOG. We can optimize these parameters by two methods: one is founding suitable theoretic models and the other is experiment. Establishing theoretic models can give one theoretic direction for improving the structure and performance of SOG, and amount of experiments can study the SOG directly. In the meantime, the measurements of some key parameters of SOG will be particular important for COIL. It will be evidential for improving the SOG.There are three important parameters that reflect the performance of SOG. They are O2 (a1 Δ) yield, chlorine utilization, and water vapor fraction at the exit of SOG. Up to now, there are many techniques and methods to be used to measure the three parameters. However, there are many questions needing to be settled because of the specialty of chemical laser. Especially, it is a difficulty to measure the O2(a1Δ ) yield accurately all along in the world. The paramagnetic resonance spectrum and photoionization methods are traditional but difficult to be applied to chemical lasers. The isothermal calorimetry method cannot be applied to the large scale COIL either because the current of electricity bridge is difficult to be balanced. Nowadays, it is popular to measure the O2 (a1 Δ) yield by using the emission spectrum and absorption spectrum. They are better methods to measure relative values because of operating easily. But they have a common problem that frequent calibration experiments are needed. The calibration will introduce large errors and make the precision down badly.In this paper, we measured the parameters of SOG for COIL by using Raman spectroscopy and absorption spectroscopy. The measurement systems were established ourselves. It is worthy notice that we firstly use one system to measure the O2 (a1Δ ) yield and the chlorine utilization at the same time in the world. It is in pursuit of accurate measurements and easy methods. The results of this paper have functions to give directions for all practical purposes, such as, improving the structure and choosing the pressure range of SOG.Firstly, we used the Raman scattering method which can calibrate in real time to measure the O2 (a1 Δ) yield of SOG for the first time in China. The measurement relative error is less than 8%. Based on the data from the experiments, we report the results that the diluent category and ratios influence the O2 (a1 Δ) yield. The relationship of P-τ values and the O2 (a1 Δ ) yield of this SOG were given. The effects of distance and bypass of gas transportation on the O2 (a1 Δ) yield are investigated. Secondly, the chlorine utilization was measured by using Raman spectroscopy simultaneously when the O2 (a1 Δ ) yield was measured. This method originated with us. The result about the chlorine utilization is coincident with other theoretic and experimental conclusions. The relationship given in this paper between gas stay time in SOG and chlorine utilization offers reference to improve the reaction efficiency and chemical efficiency of COIL. Finally, the partial water vapor pressure at the exit of SOG was measured by absorption spectroscopy. The water vapor fraction and partial pressure have trends changed with the generator total pressure, the diluentratios, and the BHP temperature. These experimental results are very important to improve experimental conditions of SOG, reduce the water vapor fraction, and enhance the output power of COIL.
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