Based on the measurement of one-dimensional （1D） optical path difference （OPD） of the supersonic turbulent bound- ary layer, an analytical form for the power spectrum of the two-dimensional （2D） OPD is obtained ...Based on the measurement of one-dimensional （1D） optical path difference （OPD） of the supersonic turbulent bound- ary layer, an analytical form for the power spectrum of the two-dimensional （2D） OPD is obtained with its structure function and under the locally homogeneous isotropic assumption. The universality of this spectrum is argued, and its validity is checked by the comparison with experimental result. The potential applications of this model in theoretical and numerical studies are emphasized. Another contribution of this work is around the application of correlation function to analyzing the statistics of OPD. Based on our results and other results published elsewhere, we show that the OPD is often not stationary, and one should be cautious about using this tool.展开更多
The aim of this study is analyzed in detail for better understanding of energy and power of an aero-engine. In this regard, this study presents energy equations were applied to the turbofan engine components. The engi...The aim of this study is analyzed in detail for better understanding of energy and power of an aero-engine. In this regard, this study presents energy equations were applied to the turbofan engine components. The engine has a thrust range of 82 to 109 kN. It consists of fan, axial low pressure compressor (LPC), axial high pressure compressor (HPC), an annular combustion chamber, high-pressure turbine (HPT) and low pressure turbine (LPT). The results show that power of the engine flow approaches a maximum value to be 82.85 MW in the combustor outlet, while minimum power is observed at LPC inlet with the value of 1.37 MW. Furthermore, important parameters of the engine are also analyzed from reverse-engineering method. It is expected that results of this study will be beneficial of power, cogeneration and aero-propulsive generation systems in similar environment.展开更多
This paper considers comparative assessment of combined-heat-and-power (CHP) performance of three small-scale aero-derivative industrial gas turbine cycles in the petrochemical industry. The bulk of supposedly waste e...This paper considers comparative assessment of combined-heat-and-power (CHP) performance of three small-scale aero-derivative industrial gas turbine cycles in the petrochemical industry. The bulk of supposedly waste exhaust heat associated with gas turbine operation has necessitated the need for CHP application for greater fuel efficiency. This would render gas turbine cycles environ-mentally-friendly, and more economical. However, choosing a particular engine cycle option for small-scale CHP requires information about performances of CHP engine cycle options. The investigation encompasses comparative assessment of simple cycle (SC), recuperated (RC), and intercooled-recuperated (ICR) small-scale aero-derivative industrial gas turbines combined-heat-and-power (SS-ADIGT-CHP). Small-scale ADIGT engines of 1.567 MW derived from helicopter gas turbines are herein analysed in combined-heat-and-power (CHP) application. It was found that in this category of ADIGT engines, better CHP efficiency is exhibited by RC and ICR cycles than SC engine. The CHP efficiencies of RC, ICR, and SC small-scale ADIGT-CHP cycles were found to be 71%, 60%, and 56% respectively. Also, RC engine produces the highest heat recovery steam generator (HRSG) duty. The HRSG duties were found to be 3171.3 kW for RC, 2621.6 kW for ICR, and 3063.1 kW for SC. These outcomes would actually meet the objective of aiding informed preliminary choice of small-scale ADIGT engine cycle options for CHP application.展开更多
针对无人机高空巡航动力性不足的问题,对某电动增压航空活塞发动机进排气系统进行了分析研究。建立了增压发动机一维仿真模型并进行了试验验证;为了提高发动机的进气均匀性,在进气系统中基于DoE(design of experiment)方法对进气稳压箱...针对无人机高空巡航动力性不足的问题,对某电动增压航空活塞发动机进排气系统进行了分析研究。建立了增压发动机一维仿真模型并进行了试验验证;为了提高发动机的进气均匀性,在进气系统中基于DoE(design of experiment)方法对进气稳压箱进行了优化改进,对比分析了改进前后进气稳压箱流场性能,流量测试结果表明:优化后的进气稳压箱最大可降低2.06 g/s的流量差异以及9.45%的进气不均匀度;为减小航空活塞发动机增压后导致的进排气短路损失,提出了排气背压阀控制策略,通过分析排气背压阀对发动机工作性能的影响得出排气背压阀开度控制MAP图,结果表明:全负荷工况下基于排气背压阀控制策略发动机在海拔7000 m时功率恢复至70.9%,比未加排气背压阀控制的发动机功率恢复效果提升了7%。展开更多
新一代战斗机和航空发动机研制对全机能量管理及发动机功率提取提出了更高的要求,迫切需要航空发动机伺服机构具备功率受限条件下正常工作的能力。针对功率受限条件下伺服机构控制目标多、约束多,传统PID控制难以满足预期的问题,提出一...新一代战斗机和航空发动机研制对全机能量管理及发动机功率提取提出了更高的要求,迫切需要航空发动机伺服机构具备功率受限条件下正常工作的能力。针对功率受限条件下伺服机构控制目标多、约束多,传统PID控制难以满足预期的问题,提出一种基于模型预测控制的最优控制方法,构建伺服机构的非线性模型,使用有限控制集(Finite Control Set,FCS)思想对输出进行解耦及线性化,综合多重目标要素设计损失函数和约束方程,从而得到了最优控制输出。仿真结果表明:在典型运行场景下,文章方法可使伺服系统实际峰值功率降低32.9%,而上升时间仅增加7.1%,实现了伺服机构的全局最优控制,为新一代飞机与航空发动机的集成研制提供了有益参考。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61008037)the National Basic Research Program of China(Grant No.2009CB724100)
文摘Based on the measurement of one-dimensional （1D） optical path difference （OPD） of the supersonic turbulent bound- ary layer, an analytical form for the power spectrum of the two-dimensional （2D） OPD is obtained with its structure function and under the locally homogeneous isotropic assumption. The universality of this spectrum is argued, and its validity is checked by the comparison with experimental result. The potential applications of this model in theoretical and numerical studies are emphasized. Another contribution of this work is around the application of correlation function to analyzing the statistics of OPD. Based on our results and other results published elsewhere, we show that the OPD is often not stationary, and one should be cautious about using this tool.
文摘The aim of this study is analyzed in detail for better understanding of energy and power of an aero-engine. In this regard, this study presents energy equations were applied to the turbofan engine components. The engine has a thrust range of 82 to 109 kN. It consists of fan, axial low pressure compressor (LPC), axial high pressure compressor (HPC), an annular combustion chamber, high-pressure turbine (HPT) and low pressure turbine (LPT). The results show that power of the engine flow approaches a maximum value to be 82.85 MW in the combustor outlet, while minimum power is observed at LPC inlet with the value of 1.37 MW. Furthermore, important parameters of the engine are also analyzed from reverse-engineering method. It is expected that results of this study will be beneficial of power, cogeneration and aero-propulsive generation systems in similar environment.
文摘This paper considers comparative assessment of combined-heat-and-power (CHP) performance of three small-scale aero-derivative industrial gas turbine cycles in the petrochemical industry. The bulk of supposedly waste exhaust heat associated with gas turbine operation has necessitated the need for CHP application for greater fuel efficiency. This would render gas turbine cycles environ-mentally-friendly, and more economical. However, choosing a particular engine cycle option for small-scale CHP requires information about performances of CHP engine cycle options. The investigation encompasses comparative assessment of simple cycle (SC), recuperated (RC), and intercooled-recuperated (ICR) small-scale aero-derivative industrial gas turbines combined-heat-and-power (SS-ADIGT-CHP). Small-scale ADIGT engines of 1.567 MW derived from helicopter gas turbines are herein analysed in combined-heat-and-power (CHP) application. It was found that in this category of ADIGT engines, better CHP efficiency is exhibited by RC and ICR cycles than SC engine. The CHP efficiencies of RC, ICR, and SC small-scale ADIGT-CHP cycles were found to be 71%, 60%, and 56% respectively. Also, RC engine produces the highest heat recovery steam generator (HRSG) duty. The HRSG duties were found to be 3171.3 kW for RC, 2621.6 kW for ICR, and 3063.1 kW for SC. These outcomes would actually meet the objective of aiding informed preliminary choice of small-scale ADIGT engine cycle options for CHP application.
文摘针对无人机高空巡航动力性不足的问题,对某电动增压航空活塞发动机进排气系统进行了分析研究。建立了增压发动机一维仿真模型并进行了试验验证;为了提高发动机的进气均匀性,在进气系统中基于DoE(design of experiment)方法对进气稳压箱进行了优化改进,对比分析了改进前后进气稳压箱流场性能,流量测试结果表明:优化后的进气稳压箱最大可降低2.06 g/s的流量差异以及9.45%的进气不均匀度;为减小航空活塞发动机增压后导致的进排气短路损失,提出了排气背压阀控制策略,通过分析排气背压阀对发动机工作性能的影响得出排气背压阀开度控制MAP图,结果表明:全负荷工况下基于排气背压阀控制策略发动机在海拔7000 m时功率恢复至70.9%,比未加排气背压阀控制的发动机功率恢复效果提升了7%。
文摘新一代战斗机和航空发动机研制对全机能量管理及发动机功率提取提出了更高的要求,迫切需要航空发动机伺服机构具备功率受限条件下正常工作的能力。针对功率受限条件下伺服机构控制目标多、约束多,传统PID控制难以满足预期的问题,提出一种基于模型预测控制的最优控制方法,构建伺服机构的非线性模型,使用有限控制集(Finite Control Set,FCS)思想对输出进行解耦及线性化,综合多重目标要素设计损失函数和约束方程,从而得到了最优控制输出。仿真结果表明:在典型运行场景下,文章方法可使伺服系统实际峰值功率降低32.9%,而上升时间仅增加7.1%,实现了伺服机构的全局最优控制,为新一代飞机与航空发动机的集成研制提供了有益参考。
