对流

The effect of each HMEon temperature, convective heat loss, evaporative heat loss,total heat loss, relative humidity, and absolute humidity ofinspiratory gases was determined.

每种汽热交换仪可测量吸入气的温度、对流热丧失、挥发热丧失、总热丧失、相对湿度、绝对湿度。

Instability of two-dimensional jets has been studied by numerical analysis and experiments based on the theoretical framework of absolute and convective instability.

在绝对／对流不稳定理论框架下，从粘性方程出发系统分析了二维均质射流稳定性。

We estimated the conditional symmetry instability by absolute and geostrophic momentem and comparative potential temperature.

利用角动量和相当位温对条件性对称不稳定进行定性判断，此次降雨过程的确存在对称不稳定和对流不稳定。

In addition,Various methods of stability analysis of wakes behind bluff bodies arediscussed,among which the general theory of absolute/convective instability is strictlyformulized from stability equations of viscous flow;the theoretical foundation of stabil-ity analysis of time-average flows is also discussed from basic equations of fluids,andthe reason for the stability analysis of time-average flow can predict the frequency inthe saturation state is explaned.

此外，讨论了钝体尾迹稳定性分析的各种方法，其中从粘性流的稳定性方程出发严格推导了绝对/对流不稳定性的理论公式；从基本方程出发探讨了采用时均流场作稳定性分析的可行性，并解释了用时均流场作稳定性分析可以更好地预示饱和频率的原因。

The basicflows are computed by a low-dimensional Galerkin method.The results confirm thattwo times global mode switching occur with increasing Re up to which the Hopf bifur-cation occurs when the absolutely unstable region cover the whole reversed flow region,and the first explanation of this phenomenon with absolute/convective instability theoryis given.

结果证实了只有当绝对不稳定性区域完全覆盖了回流区才会形成整体的Hopf分叉，此前随着Re数的增加整体模态经历了两次跳跃；并首次用绝对/对流不稳定性理论解释了这一现象。

The absolute/convective instability of incompressible swirling flows and the temporalinstability of compressible swirling flows have been fully explored, whereas the absolute/convectiveinstability of compressible swirling fl.

从N－S方程出发，通过正则模方法，研究了超声速尾涡的绝对／对流不稳定性性质。

If we consider that there is only convection, when the absolute pressure of ambient is 0.02Mpa, the theoretical value of inversion temperature is approximate to 90℃, and the experimental value, however, is 80℃~85℃.

在仅有对流换热的条件下，当环境绝对压力为0.02MPa时，"逆转温度"的理论值为90℃左右，试验值在80℃～85℃之间。

The new method is a combination of characteristic approximation to handle the convection part, to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion, a smaller time truncation is gained at the same time, and a mixed finite elementspatial approximation to deal with the diffusion part, the sealer unknown and the adjoint vector function are approximated optimally and simultaneously.

此方法即为对方程的对流项沿流体流动的方向即特征方向进行离散，从而保证格式在流动锋线前沿逼近的高稳定性，消除了数值弥散现象，并得到了较小的时间截断误差；另一方面，对方程的扩散项采用混合元离散，可同时高精度逼近未知函数及其伴随向量函数，理论分析表明，此方法是稳定的，具有最优的L~2逼近精度。

The characteristic approximation is used to handle the convection part along the direc-tion of fluid namely characteristic direction to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion; The mixed finite element spatial approximation is employed to deal with diffusion part and approximate the scalar unknown and the adjoint vector function optimally and simultaneously; In order to preserve the integral conservation of the method, we introduce the modified characteristic method.

该方法对方程的对流部分沿流体流动的方向即特征方向离散以保证格式在流动的锋线前沿逼近的高稳定性，消除数值弥散现象；对方程的扩散部分采用最低次混合有限元方法离散、同时以高精度逼近未知函数及未知函数的梯度；为保证方法的整体守恒性，在格式中引入修正项。

In section one, by using FICE scheme and TIME-GCM, a model of trace gases and OH airglow affected by gravity wave is set up, then the propagation of nonlinear gravity wave and the effect on trace gases and OH airglow are analyzed. The result shows gravity wave excited by tropospause forcing can propagate stably to the mesosphere through the stratosphere so that energy and momentum can be transferred from one region to another. In this process, gravity wave undergoes growth, overturning, convection and breaking. And the no-isothermal structure can accelerate the breaking of gravity wave in mesospause, and the breaking of gravity wave is an important source of convection and small-scale waves. The propagation of gravity wave will affect the distribution of minor species.

在第一部分的工作中，利用全隐欧拉格式和全球热层-电离层-中间层-电动力学环流耦合模式，对重力波的非线性传播及其在传播过程中对中高层大气中氧族和氢族成分和与之密切相关的OH气辉辐射的影响进行了数值模拟，结果表明，从对流层向上传播的重力波经历了产生、发展、饱和、对流产生直至破碎的非线性演化，大气的非等温结构加速了重力波在中层顶区的破碎，重力波的非线性传播是小尺度对流和湍流产生的一个重要的源。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。