查询词典 sound pressure

By using the CFD software FLUENT, the inner-flow field of centrifugal fans with ruled-surface impeller versus with enveloping surface impeller has been simulated. The static pressure distribution, the dynamic pressure distribution, the total pressure distribution, the turbulent intensity and the speed vector of the two kinds of centrifugal fans are then analyzed and compared. From the calculating results, we found that the pressure distribution, the speed vector and other parameters of the two kinds of centrifugal fans are basically same. This implies that the tool-path generating arithmetic for the machining of the impeller can meet the aerodynamic requirements of the centrifugal fan. Furthermore the method can provide proof for designing department to establish sound manufacturing tolerance for impeller.

最后采用CFD软件FLUENT，利用标准k-ε湍流模型，采用分离隐式求解器，分别对直纹面叶轮离心通风机和包络面叶轮离心通风机整体风机内部三维流场和单个通道流场进行了数值模拟计算，在计算结果的后处理中，对相同坐标值处的静压力、动压力、湍流强度和速度矢量等参数进行了分析与比较，结果表明：在相同的计算参数条件下所得到直纹面叶轮离心通风机和包络面叶轮离心通风机内部流场差别不大，从而揭示所采用的叶轮数控加工的刀位规划方法的规划误差对流体机械动力性能的影响不大，这也为设计部门制定合理的叶轮加工公差提供了依据。

Objective To study the effects of infrasound with low sound pressure level on rats with cerebral ischemia-reperfusion injury.

目的：研究低声压级次声对大鼠局灶性脑缺血再灌注损伤的影响。

Experimental results of the second harmonic sound pressure level(SPL2)curves in frequency domain show that Prof.MAA's theorydescribes the behavior of the second harmonics satisfactorily in whatis called "Steady Region" of standing wave field.

频域内，大振幅驻波场二次谐波声压级曲线的实验结果，确认马大猷教授的理论为驻波场&稳定区&的极好描述，所提理论在本实验研究中，得到了肯定结果。

It for the whole two hours frequency range speakers, and the use of high-grade titanium membrane modules Treble and bass is a high-grade cast iron and aluminum Penjia-line voice coil. Sound pressure, males, trapezoidal box design, exterior paint is imitation effect.

它为二分频全音域音箱，采用高档的钛膜高音单元，低音是高档的铁铸盆架和铝扁线音圈，声压高，爆发力强，梯形箱体设计，外观是仿喷漆效果。

The theoretical formulas about the radiation sound pressure of a complex cavity under an external force are deduced in detail.

首次提出了一种新的声固耦合分析方法——覆盖域法，详细推导了用该方法求解复杂腔体在外力作用下的辐射声场的理论计算公式，并通过实验验证了覆盖域方法的正确性。

In the experimental investigation of acoustic streaming, flow visualization techniques are used. The flow patterns of the vortex structures in the tube which transform with the variation of Sound Pressure Level of reflecting end are recorded in detail under the resonate frequency of the tube.

在对驻波声流的实验研究中，首先采用了流动显示技术对共振频率下，驻波管中稳定对称的声流旋涡结构随反射端声压级的变化作了全面细致的记录研究。

By means of the present model certain phenomena related to the nonlinear acoustic properties of an orifice, such as the roll-up of the shed vortex sheet and the forming of the Vena-Contracta are simulated. For a sinusoidal sound pressure, the time- history of the average velocity through the orifice is computed, and the nonlinear distortion of the velocity is examined by means of the Fourier decomposition.

依据此模型，对圆孔声学非线性效应的若干特征现象进行了数值模拟，如脱落涡层的卷曲，Vena收缩段的动态形成；在孔板前声压按余弦规律变化的情况下，计算了孔中平均速度的时间历程，并借助于Fourier分解分析了孔中平均速度的畸变情况。

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

Ultrasonic series: low-voltage ultrasonic Micro- sprayer, Humidification machine, Precise oil fragrant machine, Ultrasonic Contact Lens Cleaner ,Ultrasonic generator ,Ultrasonic transducer , Ultrasonic cleaning machine ,Bolt clamped Langevin transducer , Piezo-ceramic ,Portable ultrasonic sound pressure meter ,Ultrasonic cutter machine , Ultrasonic two frequency cleaning machine.

超音波系列：中华民国专利低电压超音波微雾器，超音波大雾量雾化器，水氧机，芬多精活氧吧，超音波振动子，切割刀，音压计，超音波双频清洗机，超音波高频清洗机，隐形眼镜专用超音波清洗机，高性能发振机，自动化溶剂型高洁净度清洗机。

According to the method, analysis and reconstruction sub-band filters for near perfect reconstruction oversampled filter bank are designed, then nonuniform multichannel loudness compensation based on human auditory, the sensitive feature of frequency and sound pressure level is implemented.

该方法研究了完美重构滤波器组分析与综合滤波器的设计方法，并根据人耳对频率的灵敏度特征及对声强的感知特性实现了符合人耳听觉特征的非等宽多通道响度补偿方案。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。