基于高导流量特性的发动机性能评估方法

在发动机性能分析中,高压涡轮导向器的冷却用气流量与压气机进口流量的比值为固定值。而实际涡轮冷却用气流量会受到冷气流路进出口压差、流通面积、流阻等因素的影响而发生变化,使发动机性能仿真精度与实际性能存在偏差。为进一步提高发动机的性能仿真精度,提出了一种基于高压涡轮导向器流量特性的建模方法,并以此完善了核心机性能计算模型,利用该模型对某型核心机性能参数进行计算。计算结果表明:对某型核心机,在考虑高导流量特性后,实际高导冷气量减少,且冷气量对冷气流路总压恢复系数的变化较为敏感。在核心机性能计算中采用高导冷气流量修正后,燃烧室出口总温下降1%~2%,核心机温比上升0.2%~0.45%,单位循环功增大0.24%~0.48%,核心机压比和单位循环功耗油率变化较小。

Effects of bubbly flow on bending moment acting on the shaft of a gas sparged vessel stirred by a Rushton turbine

The bending moment acting on the overhung shaft of a gas-sparged vessel stirred by a Rushton turbine,as one of the results of fluid and structure interactions in stirred vessels,was measured using a moment sensor equipped with digital telemetry.An analysis of the shaft bending moment amplitude shows that the amplitude distribution of the bending moment,which indicates the elasticity nature of shaft material against bending deformation,follows the Weibull distribution.The trends of amplitude mean,standard deviation and peak deviation characteristics manifest an "S" shape versus gas flow.The "S" trend of the relative mean bending moment over gas flow rate,depending on the flow regime in gas-liquid stirred vessels,resulted from the competition among the nonuniformity of bubbly flow around the impeller,the formation of gas cavities behind the blades,and the gas direct impact on the impeller when gas is introduced.A further analysis of the bending moment power spectral density shows that the rather low frequency and speed frequency are evident.The low-frequency contribution to bending moment fluctuation peaks in the complete dispersion regime.

天津市滨海天然气储配站工艺智能化监控系统的特点

介绍天然气储配站建立智能化操作SCADA系统，采用参变量数学模型和控制理论编制智能化监测、监控操作软件，对高压球罐储气，调峰、天然气管网用气压力、用气流量、进罐流速等控制运行方面带来的革新。

Influence of acupuncture on pulmonary function of patients with asthma： a review

Asthma is a common disease with recurrent onset which severely affects patients＇ quality of life. Acupuncture can improve pulmonary functions in asthma patients and thus treat this disorder. To summarize the status of acupuncture treatment for asthma, we have collected clinical literatures published in the recent 20 years and analyzed the influence of acupuncture on pulmonary functions in asthma patients from the aspects of frequently used points, needling techniques, manipulation and mechanisms to provide references for treating asthma with acupuncture.

Clinical study of optimizing acupoint combining in treatment of bronchial asthma with acupoint application

Objective:To observe the therapeutic efficacy of acupoint application at different groups of acupoints in treating bronchial asthma in remission stage.Methods:A total of 120 patients with bronchial asthma in remission stage were recruited and divided by the random number table method into acupoint application group 1,acupoint application group 2 and acupoint application group 3,with 40 cases in each group.In all the three groups,Tiantu(CV 22),Dazhui(GV 14)and Feishu(BL 13)were selected,with Dingchuan(EX-B 1)added in acupoint application group 1,Shenshu(BL 23)added in acupoint application group 2,and Gaohuang(BL 43)added in acupoint application group 3.Before intervention,one month and 3 months after intervention,clinical symptoms,peak expiratory flow(PEF)and forced expiratory volume in 1 second percentage of predicted value(FEV1%)of the three groups were observed,and their clinical efficacies were evaluated.Results:Comparing the therapeutic efficacy regarding traditional Chinese medicine symptoms and signs,after 1-month treatment,the total effective rate was 87.5%in acupoint application group 1,versus 62.5%in acupoint application group 2 and 55.0%in acupoint application group 3,and the between-group differences were statistically significant.After 3-month treatment,the total effective rate was 95.0%in acupoint application group 1,versus 70.0%in acupoint application group 2 and 65.0%in acupoint application group 3,and the between-group differences were statistically significant.After intervention,the three groups all showed significant improvements in pulmonary function with statistical significance;among the three groups,the improvement in acupoint application group 1 was more significant than that in the other two groups.Conclusion:Tiantu(CV 22),Dazhui(GV 14)and Feishu(BL 13)as basic prescription plus Dingchuan(EX-B 1)can improve symptoms of bronchial asthma in remission stage,and it works better in improving pulmonary function than the basic prescription plus Shenshu(BL 23)or Gaohuang(BL 43).

Structure of the Indian Ocean Meridional Overturning Circulation and its relationship with the zonal wind stress

We studied the structure of the Indian Ocean(IO)Meridional Overturning Circulation(MOC)by applying a nonlinear inertia theory and analyzed the coupled relationship between zonal wind stress and MOC anomalies.Our results show that the inertia theory can represent the main characteristics of the IO MOC:the subtropical cell(STC)and cross-equator cell(CEC).The stream function in equatorial and northern IO changes a sign from winter to summer.The anomalies of the zonal wind stress and stream function can be decomposed into summer monsoon mode,winter monsoon mode,and abnormal mode by using the singular vector decomposition(SVD)analysis.The first two modes correlate with the transport through 20°S and equator simultaneously whereas the relationship obscures between the third mode and transports across 20°S and equator,showing the complex air-sea interaction process.The transport experiences multi-time scale variability according to the continuous power spectrum analysis,with major periods in inter-annual and decadal scale.