@article{oai:jaxa.repo.nii.ac.jp:00032413,
 author = {堀, 守雄 and 安里, 勝雄 and 園田, 章人 and HORI, Morio and ASATO, Katsuo and SONODA, Akito},
 issue = {2_A},
 journal = {東京大学宇宙航空研究所報告},
 month = {May},
 note = {窒素酸化物濃度,特にN0_2濃度の測定に及ぼすガス採取プローブの影響を調べるために,5種類のプローブを用いて,メタン・空気層流予混合火炎の燃焼ガス中で測定を行った.使用したプローブは,採取ガスの冷却法,ガス流量および圧力,表面積・体積比,材質が異なっている.ガス分析には,化学発光式NO_x分析計およびガスクロマトグラフを用いた.測定結果によると,ステンレス製プローブは燃料過濃条件で,採取ガス流量の多いプローブは火炎帯に近い領域で,実際より低いNO_x濃度を与える.3種類の石英製マイクロプローブのNO_x濃度は一致し,これらの中では,実測された採取ガスの温度低下が速いか,表面積・体積比が大きいプローブが高いNO_2濃度を与える.また,いずれのプローブでも,火炎帯に近づくほど,燃料希薄になるほど,NO_x中に占めるNO_2の割合は増加する.これらの結果から,NO_x濃度の測定にはマイクロプローブを用いるのが適当と考えられるが,プローブにおけるNOとNO_2の聞の変換反応のために,プローブによりNOおよびNO_2濃度は変化し,採取ガスのquenchingが速いプローブほどNO_2の割合が増加する.従って,現段階では元の場にNO_2が存在するかどうかについて結論を下せないが,NOとNO_2の間の変換反応を最小にするquenchingの速さが存在すると考えられる., The mechanism of NO_2 formation in combustion is not understood at present, and the possibility of the conversion of NO to NO_2 in sampling probes has been suggested. The object of this experiment is to study the effect of using different probes on the analysis for the oxides of nitrogen. The combustion gas of premixed methane-air conical flame was withdrawn by five probes of idential outer geometry but of different cooling methods, sample rates, surface to volume ratios and materials, and analyzed by a chemiluminescent NO_x analyzer and a gas chromatograph. The probes of larger sample rates and a stainless-steel probe gave substantially lower levels of NO_x, near the flame zone and at fuel-rich condition, respectively. On the other hand, the quartz probes with fine orifices gave almost the same levels of NO_x. The levels of NO_2 measured by these quartz probes and the temperature profiles in the probes showed that a probe having a larger surface to volume ratio and a faster cooling rate gave a higher level of NO_2. NO_2/NO_x ratios measured by all probes increase as the sampling position approaches the flame zone, and also increase as the equivalence ratio decreases. In conclusion, analysis for NO_x using a quartz probe with fine orifice may be recommended. However, the more efficient the quenching of the sample becomes, the higher the level of NO_2 due to the interconversion between NO and NO_2 in the probe. It is supposed that a optimum quenching rate would be present to minimize the interconversion., 資料番号: SA0125640000},
 pages = {769--784},
 title = {<論文>窒素酸化物濃度の測定に及ぼすガス採取プローブの影響に関する実験的研究},
 volume = {14},
 year = {1978}
}