对流

In order to acquire the heating-cooling process of laser molten pool and the mutual effect of sintering layers in multi-layer powder sintering, factors such as heat conduction, heat radiation, heat convecting and changeable thermophysical property parameters were taken into account comprehensively, the 3D transient state FEM of the temperature field of multi-layer thin-wall metal parts formed by DMLS was established based on ANSYS. The APDL (ANSYS Parametric Design Language) was used to carry out thermal resource moving and the technique of birth/death for element was used to simulate the process of material addition.

为掌握多层粉末烧结过程中激光熔池的加热冷却规律以及各烧结层之间的相互影响，综合考虑热传导、热辐射和热对流以及材料的高度非线性，基于ANSYS平台建立了多层金属薄壁件的三维温度场有限元模型，利用APDIJ语言编程实现模拟中激光热源的移动，采用&单元生死&技术描述粉末材料动态增长过程。

Warm air convecting upward.

暖空气因对流作用而上升。

The break-off and cumulates of subducted slab would give rise to the upwelling of mantle material and then thermal -chemical erosion of lithospheric roots happened.

俯冲板片断离及在深部地幔中的堆积，必然引起地幔物质的对流，从而产生地幔羽，上升的地幔羽对岩石圈底部发生热侵蚀和化学侵蚀，并在薄弱地带上升喷出地表或侵入在地壳浅部，形成了广泛而强烈的岩浆作用。

Equations are differenced by control volume algorithm , convection term is differenced by up wind difference algorithm , diffusion term and continuity equation are differenced by central difference algorithm .

采用控制容积法对控制方程组进行离散，对流项采用迎风差分格式，扩散项、连续方程采用中心差分格式。

It has been proved that the convection heat transfer coefficients increased by several times with gas discharges.

在气体放电强化传热的作用下对流传热系数获得数倍的增加。

The YW(subscript 25G) train corn partments were studied, and passengers and several kinds of barriers (including desks, racks, dosses, seats) were taken into account for airflow. The k-ε turbulence model was applied for numerical simulation of indoor fluid flow and age of air, and the air exchange efficiency was obtained.

笔者以YW(下标 25G)型空调硬卧列车车厢为研究对象，在物理模型中考虑了旅客以及车厢内各障碍物（包括边桌、行李架、床铺、折座）等对流场的影响，采用k-ε湍流模型及数值模拟的方法，对硬卧车厢内流场及空气龄的分布变化规律进行研究，从而得到车厢内的换气效率。

They are likely composed of ammonium hydrosulfide with possibly a mixture of materials dredged up from the depths.

这些和北极的云层类似的云层可能是一种对类似于雷暴的对流现象，由氢硫化铵和可能从大气深处流出的混合物质组成。

On the basis of solute transport theory, the coal gangue eluviated in Xinqiu in Fuxin coal miming area was studied for the pollution of groundwater. The mechanism of coal gangue eluviated in the aquifer was analyzed. A coupled numerical model was developed with convection、sorption and dissolve、disintegration for simulating the leachate transport in groundwater. The model was discreted by using a Gelarkin finite-element method and a Picard iteration scheme, and the process of coal gangue leachate was presented, which predict the temporal and spatial distribution features of contaminant concentration. The result indicates that the contaminated plume is continually extended as time increases, and the vertical diffusion is more abvious.

以溶质运移理论为基础，针对阜新市新邱露天煤矿煤矸石淋滤液对地下水污染实际情况，分析了煤矸石渗滤液在含水层中运移的规律，在综合考虑对流扩散、吸附解吸、生物降解条件下建立了淋滤液在地下水中运移的耦合动力学数学模型，采用Galerkin有限元方法和Picard迭代法相结合对耦合模型进行了离散，模拟了淋溶液对地下水污染的动态过程，预测了污染浓度的时空分布特征，并结合实际观测数据进行对比。

GFC is composed of flow-control mechanism and feed-back mechanism. The former mechanism allocates the bandwidth and schedules the delivery of packets based on the priority of the data and the length of the sending queues; the latter mechanism emendates and adjusts the traffic control parameters based on the feed back information of the TCP.

该算法由流控机制(Flow-ControlMechanism)和反馈机制(Feed-Back Mechanism)两部分组成，流控机制根据组播报文的优先级和长度对各个发送队列中的报文进行带宽分配和发送调度；反馈机制基于TCP的反馈信息对流控参数进行实时校正和调节，进而有效地减少报文的丢失率。

Various value of mass transfer number and the oxidizer mass flux were considered in the calculation. The regression rate of the solid fuel was formulized based on the calculation.

为了深入了解混合燃烧的机理，在1963年由Marxman等[3]提出了基于边界层燃烧的对流传热控制模型，该模型假定燃烧发生在固体燃料升华表面上的边界层中的一个相对薄的火焰层中。

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％。