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双语推荐：声速

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声速经验公式是海水中温度、盐度和静压力的函数,通过对直接测量声速和间接测量声速的分析,并应用近年来收集的南海声速剖面仪SVP和CTD数据,对九种声速经验公式计算的声速与直接测量声速的差异进行了分析,得出了声速经验公式的计算差异范围,结果表明各个声速经验公式各有优势,不同的公式适用的范围也不一样,并给出了在不同的范围内应用何种声速经验公式能获得较高精度的结论。
Empirical equation for sound velocity is the function of temperature, salinity and static pressure in sea water. After analyzing the sound velocity by direct measurement and indirect measurement, and utilizing the data collected by profiler SVP and CTD in South China Sea in recent years, the differences between the sound velocities calculated by nine kinds of empirical equations and the one with direct measurement are studied. The different scopes calculated by em-pirical equations for sound velocity are obtained. The result shows every empirical equation of sound velocity has its own advantage and their applicable scopes also differ. The conclusion is provided for using an appropriate empirical equation for sound velocity in actual situation to get higher accuracy.

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从声速误差来源进行分析，探讨了目前长江航道水深测量中声速测量的现状，并对长江上不同水道的声速进行长达4a的声速测量和数据分析，通过数据分析长江航道水深测量中影响声速的各种因素，从而发现规律，最后提出了一些减少声速测量误差对水深影响的相关方法。
This article analyzes the sources of velocity error discusses the current status of sound velocity measurement in the Yangtze River channel s bathymetric survey and carries out sound velocity measurement of 4 years and data analysis to find out the factors influencing the sound velocity and achieve the law.Means of reducing the influence from the sound velocity error on the bathymetric survey are provided.

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声速剖面(SVP)在多波束测深中不可或缺。为解决原始测量的声速剖面数据量大而影响工作效率的问题,本文进行了声速剖面的精简与优化研究。提出一种适用声速剖面数据精简运算的改进DP算法(MOV方法),通过射线追踪法和误差百分比分析法评估精简前后的声速剖面对测深精度的影响,并利用实测声速剖面数据对该算法进行了验证。结果表明,通过优选算法阈值,声速剖面数据的简化率在90%以上,可控制水深标准差百分比在0.1%以内,优化后的声速剖面可大幅提升多波束勘测与数据处理工作效率,具有重要的工程实际应用价值。
Sound velocity profiles (SVPs)are indispensable in the multi-beam echo sounding.To solve the problem of multi-beam survey and data processing efficiency due to great capacity of SVP data,an improved D-P algorithm (MOV method)is presented in this paper,which is applied to SVP streamlining and optimization.By ray tracing and percentage error analysis,the impact on sounding data accuracy before and after using streamlined SVP was evaluated,then measured SVP data and multi-beam sounding data were used to validate our method.The results showed that,by optimizing the threshold,the reduction rate of SVP data was 90% or more,the standard deviation percentage error of depth was controlled within 0.1%.Using the optimized SVP data will significantly improve multi-beam survey and data processing efficiency,indicating its practical engineering application value.

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利用USB独立声卡结合虚拟仪器软件LabVIEW开发了声速测量系统,研究了声速与空气的温度、湿度之间的关系,得到了温湿度修正的声速经验公式.
Using USB sound card and LabVIEW software ,a sound speed measurement system was set up .The relationship between sound speed and air temperature and humidity was studied using this system .A revised empirical formula for temperature and humidity dependent sound speed was al-so obtained .

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钱学森先生1945年在论文《论高超声速相似律》中,首次提出了高超声速(hypersonic)的术语.高超声速飞行器具有的强大的军事和民事应用前景,20世纪80年代初,在世界上掀起了研究和发展高超声速飞行器的热潮,其中高超声速飞行器控制是其关键科学和技术问题之一.高超声速飞行器的研究取得了大量理论成果,与其形成鲜明对比的是,高超声速飞行器在试飞实验中却遇到了很大困难,例如X–51A, HTV–2.这种现象不得不引发我们进行深入思考.由于高超声速空气动力学研究的局限性,导致目前所建立的高超声速飞行器的动力学模型,与真实系统相比,其结构和参数不确定性非常大,它从根本上限制了控制理论和方法的研究.并且由于高超声速飞行器动力学模型的复杂性,导致目前工程应用中的控制方法复杂化.因此,针对高超声速飞行器控制问题,需要深入开展气动、控制交叉学科的研究,以及适于工程应用的自适应控制的研究.针对上述问题,我们开展了一定的研究.我们建立了三轴耦合的高超声速飞行器被控对象类X–20及其气动模型,并结合工程应用,直接针对表格形式的气动模型开展控制研究.针对强耦合和无解析动力学的控制问题,特征模型理论有其独特优势.近年来,我们系统研究了基于特征模型的高超声速飞行器
Tsien Hsue-shen proposed the terminology hypersonic in the paper“similarity laws of hypersonic flow”for the first time in 1945. Hypersonic flight vehicles have strong military and civil application prospects, where the control of hypersonic flight vehicles is one of the key science and technology problems. The researches of hypersonic flight vehicles have made great progresses; while there have been great difficulties in the test of them, for example, X–51A and HTV–2. This phenomenon has to trigger us to think profoundly. The restriction of the research of aerodynamics results in the current dynamic models with significant uncertainties of structure and parameters compared with the true vehicles, which restricts fundamentally the research of its control theory and approach. And the complexity of the hypersonic dynamics results in the complication of the control method in engineering. Hence, for the hypersonic flight vehicle control problem, we need to the study the interd

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传统的驻波干涉法采用声压极大值测声速,受示波器屏幕尺寸限制,灵敏度差.详细分析了驻波共振干涉法测声速的原理,确定了声压极小值测声速的理论依据.用声压极小值法测定了声速,实验结果表明:该方法比声压极大值法更好操作且误差更小.
Traditional stationary wave interferometry was a kind of maximum sound pressure method which was used to measure sound velocity .Restricted by the screen size of the oscilloscope , the sensitivity was poor .The stationary wave resonant interference method was analyzed in detail in this paper .The theoretical basis of minimum sound pressure method was found out .Experimental re-sults indicated that this method was better than the maximum sound pressure method ,and the error w as smaller .

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本文设计了一套适用于不同温度、压力及不同介质条件下的超声波声速测量系统，该系统的声速测量采用游标卡尺鉴相法，该方法的测量精度较高，可以达到0.000589rad。通过对零相位情况下的电路的测试结果分析，该测量方法方便可行，能达到设计要求。该超声波声速测量系统进行超声波声速特性的研究，能够得到不同介质、温度和压力下的超声波声速的补偿方法，并为超声波技术在流量计量测试领域的进一步发展提供借鉴。
One kind of measuring system for ultrasonic velocity is presented. This system can study the ultrasonic velocity characteristics under different temperatures, pressures and mediums. The measurement of velocity in the system use the method of vernier caliper phase meter, and the measuring accuracy of phase is relatively high and can reach to 0.000589rad, In our system, the maximum length of the testing pipe is 1.04 m. After the system was tested under the basic circumstance, we conclude that this method is convenient and feasible and the system can meet the prospective requirements. We can obtain the ultrasonic velocity compensation method under different mediums, temperatures and pressures by perform on experiments in our system. It is valuable for the development of the ultrasonic measuring field.

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为了克服共振干涉法在液体的热力学声速和高频声速测量方面精度不高的问题，本文建立了一种基于自发布里渊散射原理的测定液体声速的实验装置.利用法布里-珀罗干涉仪对散射光进行扫描滤波，数据采集卡结合光子计数器对散射光进行探测，设计了一种散射光信息采集分析方法.该实验方法有效的解决了传统布里渊散射方法中信号失真的问题，显著地提升了液体声速测量精度.对308.6—906.2 MHz内298.15 K饱和液相CCl4声速进行了测量，测量结果与文献值具有较好一致性.利用法布里-珀罗干涉仪周期性扫描的滤波原理，通过在测量得到的布里渊频移上加减整数倍个自由波谱区，得到了更大频率的波谱信息，进而设计一种测定介质高频声速的方法.对CCl4在5406.1—5521.0 MHz频段内的声速进行了测量.实验结果显示， CCl4的热力学声速随频率无明显变化，而高频声速随频率的增大呈增大趋势且远大于热力学声速，证实CCl4具有色散现象.
In order to overcome the problem of poor accuracy of resonant interferometer method in the measurement of thermodynamic sound speed and hypersound speed of liquids an experimental setup for measuring the sound speed of liquids is established based on the principle of spontaneous Brillouin light scattering. A Fabry-Perot interferometer is used to filter the scattered light and a data acquisition card as well as a photon counting head is used to detect and analyze the scattered light, then a data acquisition and analysis method of scattered light is presented. This method overcomes the limitation of the signal distortion in conventional Brillouin light scattering and increases the measuring accuracy of the sound speed of liquids remarkably. The sound speed of saturated liquid CCl4 is measured in the frequency range of 308.6 to 906.2 MHz at 298.15 K. Results agree well with the data reported in the literature, and show that the experimental method is feasible. In addition, the m

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研究临近空间高超声速导弹的红外辐射特性，对于反临近空间武器系统侦察监视临近空间目标具有重要意义。通过对临近空间高超声速导弹 X-51 A 试验飞行过程的研究，深入分析了高超声速导弹的红外辐射特征，并建立其红外辐射模型。以导弹蒙皮、发动机及尾喷焰作为高超声速导弹的主要红外辐射源，以 X-51 A 试验飞行器为参考，计算临近空间高超声速导弹在3～5μm 和8～14μm 波段在不同方向上的红外辐射强度，并针对计算结果进行了分析。
It is important for defending near space weapons and detecting near space targets to study the infrared radia-tion characteristics of near space hypersonic missiles.By studying the near space hypersonic missile X -51 A′s flight test,the infrared radiation characteristics of hypersonic missiles are analyzed,and its infrared radiation model is estab-lished.The missile skin,engine and tail flame are reguarded as the primary infrared radiation sources of hypersonic missile.Taking X -51 A test vehicle as a reference,the infrared radiation strength of near space hypersonic missiles is calculated at different directions in 3 ~5 μm and 8 ~1 4 μm waveband,and the calculation results are discussed.

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分析了高超声速飞行器的优势,阐述了多种高超声速全球/远程打击飞行模式的特点。指出涡轮基组合循环(TBCC)动力水平起降机载发射高超声速弹道飞行模式,在平台机动性、发射隐蔽性、突防概率等方面都具有明显优势,且可有效牵引TBCC发动机、水平起降高超声速发射平台、小型机载战略武器技术分阶段渐进发展,在未来能量中心战中将发挥重要作用。
Superiorities of hypersonic aerial vehicle were analyzed and the characteristics of various hyper-sonic Global/Long-range strike modes were illustrated. A new hypersonic ballistic flight mode based on HTHL aircraft with TBCC was introduced. It was superior to conventional strike modes in the flexibility of launch platform, the hidden property of launching and the probability of penetration, etc. This strike mode can effectively guide the progressive development of TBCC, HTHL hypersonic launch platform and the small strategic weapon launched by aerial vehicle. Therefore, it is believed that this strike mode will play a significant role in the future energy-centric warfare.

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