Experimental investigation of lean premixed pre-vaporized liquid-fuel combustion in porous media burners at elevated pressures up to 20 bar
Experimental investigation of lean premixed pre-vaporized liquid-fuel combustion in porous media burners at elevated pressures up to 20 bar
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DOI：
10.1016/j.combustflame.2019.10.033
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发表时间：
2020-02
影响因子：
4.4
通讯作者：
Sadaf Sobhani;J. Legg;D. Bartz;J. Kojima;Clarence T. Chang;J. D. Sullivan;J. Moder;M. Ihme
中科院分区：
文献类型：
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作者：
Sadaf Sobhani;J. Legg;D. Bartz;J. Kojima;Clarence T. Chang;J. D. Sullivan;J. Moder;M. Ihme
多孔介质中的燃烧已被确定为实现更高的燃烧速率、扩展可燃极限和减少排放的有前途的技术。为了评估该技术应用于航空燃气涡轮发动机的可行性，实验研究了多孔介质燃烧器（PMB）在高压下使用预蒸发液体燃料的性能。PMB在0.4和0.55之间的贫燃料当量比下在高达20巴的压力下与完全预蒸发和预热的正庚烷以及8巴的气态甲烷一起操作以用于性能比较。燃烧稳定性图沿着报告温度分布、压降以及稳定操作条件下的CO和NOx排放。这些实验的结果表明，PMB在高压条件下具有优异的性能。此外，使用体积平均，一维反应流方程的数值模拟补充了实验测量，以提供进一步的洞察力的压力和燃料混合物对火焰结构的影响。最后，高分辨率的es X射线计算机断层扫描（XCT）是用来检查的多孔基质的结构完整性，在高压燃烧操作，显示微裂纹的证据和增加的表面粗糙度，由于碳化硅氧化。大规模的缺陷没有观察到四天的循环高压测试后，在很宽的范围内的压力，加热速率，和当量比。
Combustion in porous media has been identified as a promising technology for achieving higher burning rates, extending flammability limits, and reducing emissions. To assess the viability of this technology for application to aviation gas-turbine engines, the performance of a Porous Media Burner (PMB) operated with pre-vaporized liquid fuel at high pressures is experimentally examined. The PMB was operated at fuel-lean equivalence ratios between 0.4 and 0.55 at pressures up to 20 bar with fully pre-vaporized and preheated n-heptane as well as gaseous methane at 8 bar for performance comparison. Combustion stability maps are reported along with temperature profiles, pressure drops, and emissions of CO and NOxat stable operating conditions. Results from these experiments show excellent performance of PMBs at high-pressure conditions. Additionally, numerical simulations using the volume-averaged, one-dimensional reacting flow-equations complement the experimental measurements to provide further insight into the effects of the pressure and fuel mixture on the flame structure. Lastly, high-resolution es X-ray Computed Tomography (XCT) is used to examine the structural integrity of the porous matrix during the high-pressure combustion operation, showing evidence of micro-fissures and an increase in the surface roughness due to SiC-oxidation. Large-scale defects were not observed after four days of cyclic high-pressure testing over a wide range of pressures, heating rates, and equivalence ratios.