英语翻译Fig.6 shows the completed open jet wind tunnel inside theISVR’s anechoic chamber (control valve and primary silencer arein the roof space of the chamber and are not shown in the figure).Also shown is the new coordinate system (x,y,z) em

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/23 03:46:43
英语翻译Fig.6showsthecompletedopenjetwindtunnelinsidetheISVR’sanechoicchamber(controlvalveandprimarysile

英语翻译Fig.6 shows the completed open jet wind tunnel inside theISVR’s anechoic chamber (control valve and primary silencer arein the roof space of the chamber and are not shown in the figure).Also shown is the new coordinate system (x,y,z) em
英语翻译
Fig.6 shows the completed open jet wind tunnel inside the
ISVR’s anechoic chamber (control valve and primary silencer are
in the roof space of the chamber and are not shown in the figure).
Also shown is the new coordinate system (x,y,z) employed for the
cross section of the nozzle exit plane.We now present the overall
facility background noise characteristics for the entire rig as a function
of exit jet velocity.The flow uniformity and turbulence intensity
variation over the jet nozzle of the jet were also measured and
are also presented below.Note that both the acoustic and aerodynamic
measurement results are plotted using the new coordinate
system (x,y,z) as defined in Fig.6.
4.1.Analysis of background noise levels
A microphone was placed at (x,y,z) = (0,0.5,0),i.e.0.5 m vertically
above the centre of the cross-sectional nozzle exit plane to
measure the background noise level inside the anechoic chamber
at different exit jet velocities.This corresponds to a polar angle,
h = 90\2,where h is the angle from the jet axis,as shown in Fig.1.
In addition,another microphone was placed at h = 45\2 (0.35,0.35,
0) to assess the noise directivity of the exit jet.Fig.7a and b show
the narrowband (spectral density) sound pressure level at h = 45\2
and 90\2,respectively pertaining to the open jet wind tunnel over
a range of jet velocities between 33.1 and 99.6 ms\41.These figures
are plotted in the form of power spectral density with a 1 Hz bandwidth
and a frequency resolution,Df of 6.25 Hz.The spectra are
smoothly varying and decay slowly with frequency.
It is also insightful to examine how the sound pressure level
varies with jet velocity as the function of frequency.Fig.8 shows
the dependence of sound pressure level on jet velocity,p2 / VN
for h = 45\2 and 90\2.For h = 45\2,the sound pressure level is observed
to scale as V7.5–V8 in the frequency range between 400 Hz and
10 kHz.This power law is classically associated with quadrupole
jet mixing noise.For h = 90\2,a power law of V6.5 in the frequency
range 100 Hz–2 kHz is observed.This velocity dependence implies
that dipole aerodynamic noise sources are dominant at this measurement
angle.One possible dipole noise source is due to the
boundary layer being scattered at the nozzle lip.Another possible
dipole noise contributor at this frequency range could be due to the
noise breakout from inside of the rig.From 2 kHz and above,the

英语翻译Fig.6 shows the completed open jet wind tunnel inside theISVR’s anechoic chamber (control valve and primary silencer arein the roof space of the chamber and are not shown in the figure).Also shown is the new coordinate system (x,y,z) em

Fig.6 shows the completed open jet wind tunnel inside the ISVR’s anechoic chamber (control valve and primary silencer are in the roof space of the chamber and are not shown in the figure).图6示出了在英国南安普顿大学声与振动研究所(ISVR)消声室(控制阀和主消声器是在消声室的屋顶空间,在图中没有显示)内的完整的开放式风洞.Also shown is the new coordinate system (x,y,z) employed for the cross section of the nozzle exit plane.示出的还有用于喷嘴出口平面横截面的新坐标系统(x,y,z).We now present the overall facility background noise characteristics for the entire rig as a function of exit jet velocity.现在我们介绍整个装置(rig)总的设施背景噪声特性与出口射流速度的函数关系.The flow uniformity and turbulence intensity variation over the jet nozzle of the jet were also measured and
are also presented below.在射流喷嘴范围的流动均匀性和湍流强度变化也进行了测量,并在下面加以介绍.Note that both the acoustic and aerodynamic measurement results are plotted using the new coordinate system (x,y,z) as defined in Fig.6.请注意,声学和空气动力学的测量结果都用新的坐标系统(x,y,z)绘制,入图6所示.
4.1.Analysis of background noise levels
背景噪声水平的分析
A microphone was placed at (x,y,z) = (0,0.5,0),i.e.0.5 m vertically above the centre of the cross-sectional nozzle exit plane to measure the background noise level inside the anechoic chamber
at different exit jet velocities.在(x,y,z)=(0,0.5,0)处,即在横截面的喷嘴出口平面中心正上方0.5m处放置一个麦克风,以测量不同出口射流速度下消声室内的背景噪声水平.This corresponds to a polar angle,h = 90 ,where h is the angle from the jet axis,as shown in Fig.1.这相当于h=90度的极角,这里,h为离开射流轴线的角度,入图1所示.In addition,another microphone was placed at h = 45 (0.35,0.35,0) to assess the noise directivity of the exit jet.此外,在h=45度(0.35,0.35,0)处放置另一个麦克风,以评估出口射流的噪声方向性.Fig.7a and b show the narrowband (spectral density) sound pressure level at h = 45 and 90 ,respectively pertaining to the open jet wind tunnel over a range of jet velocities between 33.1 and 99.6 ms 图7a和b分别示出了在h=45度和90度时,关于射流速度在33.1和99.6m/s之间范围时开放式风洞的窄带(谱密度)声压水平.1.These figures are plotted in the form of power spectral density with a 1 Hz bandwidth and a frequency resolution,Df of 6.25 Hz.这些图是以1Hz带宽的功率谱密度和Df为6.25Hz的频率分辨率的形式绘制的.The spectra are smoothly varying and decay slowly with frequency.该谱平滑变化,并随频率缓慢衰落.It is also insightful to examine how the sound pressure level varies with jet velocity as the function of frequency.研究声压水平作为频率的函数如何随射流速度变化也是很有见识的.Fig.8 shows the dependence of sound pressure level on jet velocity,p2 / VN for h = 45 and 90 .图8示出了,声压水平与射流速度的依存关系,在h=45度和90度下p2
/VN.For h = 45 ,the sound pressure level is observed to scale as V7.5–V8 in the frequency range between 400 Hz and 10 kHz.在h=45度时,在400Hz和10kHz之间的频率范围,观察到的声压水平标度为V7.5-V8.This power law is classically associated with quadrupole jet mixing noise.For h = 90 ,a power law of V6.5 in the frequency range 100 Hz–2 kHz is observed.这一幂率经典来说与四极射流混合噪声相关联.在h=90度时,在100Hz-2kHz的频率范围观察到了V6.5的幂率.This velocity dependence implies that dipole aerodynamic noise sources are dominant at this measurement angle.这一速度依存关系表明了,双极空气动力学噪声源在这一测量角度时是主导性的.One possible dipole noise source is due to the boundary layer being scattered at the nozzle lip.Another possible dipole noise contributor at this frequency range could be due to the noise breakout from inside of the rig.一个可能的双极噪声源是由于边界层在喷嘴唇部被散射而引起的.在这一频率范围,另一个可能的双极噪声贡献源可能是由于在装置(rig)内部的噪声爆发而引起的.From 2 kHz and above,the从2kHz及以上,……

英语翻译Fig.11a shows the velocity profiles of the plane parallel to thejet axis (x–y plane) at z = 0 between streamwise distance,x of 0.1and 1.3 m with an increment of every 0.1 m.Fig.11a shows theevolution of the jet velocity profile and its 英语翻译Fig.2 shows the INS process..There are two main phases for INS operation:the alignment phase and the navigation phase.The navigation phase starts from the initial velocity,position and attitude.The process for determining these INS initia 英语翻译Fig.6 shows the completed open jet wind tunnel inside theISVR’s anechoic chamber (control valve and primary silencer arein the roof space of the chamber and are not shown in the figure).Also shown is the new coordinate system (x,y,z) em 英语翻译Today the true north Great Circle of direction is the reference for direction measurement.Direction is expressed as degrees of Bearing angle or degrees of Azimuth angle.Fig.7.1 shows the Great Circle and illustrates the relationship betwe 英语翻译Fig.1 shows that diamond particles are dispersed in thecopper matrix.Since the diamond particles are easy to bestripped off during mechanical polishing,small pits are lefton the surface of samples.When the samples were analyzedby electron 英语翻译内容如下,The differences between results obtained with the full potential equation and those obtained with the small-perturbation potential equation are graphically illustrated in Fig.14.9,which shows data calculated by Keyfitz et al. 英语翻译To implement the relational model for the same partial LIMS schema presented in Fig.1 for the hierarchical model,tables would need to be created for each entity relationship in the schema.Fig.3 shows the mapping required in the relational 英语翻译Fig.7 shows 3D images and surface roughness of the Siwafer by AFM to compare the unimplanted with implanted surface.Roughness of Si-wafer before N+ ion implantation is about 6 Å while it reduced to about 3 Å after implantation 英语翻译Fig.2 shows that the level of the input power flow decreases with the reduction of the stiffness of the continuous isolator.But too soft continuous isolators can result in not only a difficulty in the strength and technology of the struct 英语翻译Fig.3 shows the DR UV–vis spectra of the (Co,H)-Y,the (Co,H)-Beta and as an example of the (Co,H)-Beta/Y (II).The spectra of other composites are similar to that of this sample.By deconvoluting the spectra with origin 6.1,six bands at a 英语翻译The R-S Flip-Flop.We can realize the latch function with standard logic gates.Fig.4.17 shows a latch constructed from tow NOR gates.The output of each NOR provides one of the inputs for the other NOR.The other inputs are labeled S(for SET 英语翻译As is clear from the nature of the process,a key factor in determining the amount of final shrinkage is the unit water content of the fresh concrete.This isillustrated in Fig 2.9,which shows the amount of shrinkage foe varying amountsof m 英语翻译2.Control strategyThe proposed method improves the dynamic stability of the ac system by transmitting a suitably modulated dc power in the ac transmission line by injection into the transformer neutrals at either end.Fig.1 shows the ac tr 英语翻译Fig.3 shows the FPGA-internal block diagram.The three in¬terfaces,serial AER,parallel AER and USB are drawn in orange.The USB interface,as opposed to the other interfaces,is handling explicitly timestamped addresses.Thus we need moni 英语翻译Fig.3 shows the FPGA-internal block diagram.The three in¬terfaces,serial AER,parallel AER and USB are drawn in orange.The USB interface,as opposed to the other interfaces,is handling explicitly timestamped addresses.Thus we need moni 英语翻译Both figures show that the system can effectively analyze water quality.Fig.5 shows that the measured water quality remained well below the warning line (i.e.,the COD level at which additional water must be released to maintain water qual 英语翻译Fig.12 shows the simulation results for 45º and -45º dual-polarized array antennas with VSWR and return loss of 1.299 and -17.72 dB respectively at the resonant frequency.Again,this proves that the combination of more patches in 英语翻译Strains caused by dynamic and static loads were taken in thisstudy for two main purposes.The first purpose was to detect thepresence of cracks in the test slab.Fig.8 shows the change indynamic strain as measured by Strain Gauge 3 before a