Quantitative vapor temperature imaging in DISI-sprays at elevated pressures and temperatures using two-line excitation laser-induced fluorescence
Quantitative vapor temperature imaging in DISI-sprays at elevated pressures and temperatures using two-line excitation laser-induced fluorescence
复制标题
使用两线激发激光诱导荧光在高压和高温下对 DISI 喷雾进行定量蒸气温度成像
DOI：
10.1016/j.proci.2012.05.093
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
A. Leipertz
中科院分区：
文献类型：
--
作者：
J. Trost;L. Zigan;A. Leipertz
喷雾引导混合气形成的直接喷射(DI)概念是提高火花点火(SI)发动机效率的一种很有前途的方法。燃料和温度分布决定了蒸发和点火行为。然而，由此产生的混合物和温度在燃烧室中并不均匀。此外，它还受到燃料蒸发特性的强烈影响，现代生物燃料的蒸发特性与汽油不同。本文介绍了基于3-戊酮的双线激励激光诱导荧光技术在延迟喷雾时间条件下精确测定喷雾平面温度的方法和能力。测定了蒸发热有显著差异的汽油代用燃料异辛烷和生物组分乙醇的喷口温度分布。利用两种不同的准分子激光准同时激励的方法，分析了光学可接近燃烧试验台中六孔螺线管喷油器的喷雾过程。信号由一个双快门ICCD摄像机记录。根据图像的信号比可以计算出燃油喷雾内的温度场。该示踪剂是用增强型高温校准池校准的，温度高达700K，压力高达1 MPa，这与所研究的条件有关。对后处理策略进行了高精度和高精度的优化。在喷雾中的不同位置和在乙醇最高141K的喷注中显示较大蒸发冷却的时间，对燃料喷雾行为进行了评估。为了比较总体平均结果，在相同的边界条件下建立了CFD-喷雾模型，表现出非常相似的趋势。温度图像的单次精度约为5.6%，不精确度为3.8%，这使得该技术能够用于模型改进和验证。
Direct-injection (DI) concepts with spray-guided mixture formation are promising methods to increase the efficiency of spark ignition (SI) engines. The fuel and temperature distribution determines evaporation and ignition behavior. However, the resulting mixture and temperature are not homogeneous through the combustion chamber. Furthermore, it is strongly affected by the fuel evaporation properties, which are different for modern biofuels compared to gasoline. The present paper demonstrates the procedure and the capability of two-line excitation LIF based on 3-pentanone for accurate planar temperature determination in DISI-sprays at late injection timing conditions. The jet temperature profiles were determined for the gasoline surrogate fuel iso-octane and the biogenic component ethanol, which have a significant difference in their heat of evaporation. The spray of a 6-hole solenoid-injector in an optically accessible combustion test rig is analyzed by quasi-simultaneous excitation by two different excimer lasers. The signals are recorded with one double-shutter ICCD-camera. From the signal ratio of the images the temperature field in the fuel spray can be calculated. The tracer is calibrated with an enhanced high temperature calibration cell for temperatures up to 700K and pressures up to 1MPa, which are relevant for the studied conditions. The postprocessing strategy is optimized regarding high accuracy and precision. The fuel spray behavior is evaluated at different positions in the spray and times showing larger evaporation cooling in the jet of maximum 141K for ethanol. For a comparison of the ensemble averaged results a CFD-spray model was set up under the same boundary conditions showing very similar trends. The temperature images yielded a single-shot precision of approximately 5.6% and inaccuracies of 3.8% making this technique capable for model improvements and validation.