查询词典 heat transfer

The flow parameters, which controlled the heat transfer phenomena in the coolant channel of the piston, are identified; the experimental facilities and program will be established in accordance with the parametric conditions experienced by a real marine diesel engine. The experimental result for the flow within smooth-walled duct under the reciprocating motion will be used as the reference datum to assess the results for the study of heat transfer augmentation. As an attempt to enhance the cooling performance, the ribs will be installed in the coolant channels which flow was orthogonal mode for the piston moving direction. Finally, the results obtained for the tests with heat transfer augmentation devices will be compared with the smooth-walled test results.

本研究计画利用座标转换理论，对受到与往复运动正交方向之流场进行参数分析，建立控制此流场热传性能之参数后，模拟实际船舶主机运转时活塞之冷却情形并进行实验量测，作为评估活塞冷却之基准，然后应用现行已实用於工业界的技术，在与往复运动正交方向之圆形冷却通道中加装凸起物以增加热传效能并予以测量其热传系数及其相关之物理现象，据以讨论此流场受往复力之影响，在周向不同位置之热传情形以及其与平行於往复运动方向之流场的差异。

To understand the different heat transfer characteristics of regenerative cooling in plug nozzle at different operating conditions, computational model of two dimensional plug nozzle and internal nozzle were established and numerical simulation was employed. Heat transfer results of the internal nozzle and the parameter distribution at the outlet were obtained. Flowfield and heat transfer characteristics of the plug at different operating conditions with different coolant flow rates were investigated.

为了解塞式喷管发动机高低空不同的再生冷却换热特性，分别对二维型面内喷管和塞锥建立计算模型，采用数值模拟的方法，得出内喷管的冷却换热结果和出口参数，重点研究了塞锥在地面和设计点工作时的不同换热特性及其冷却剂流量的影响。

Based on the theoretical of ice slurry phase flow and heat transfer, established a heat transfer model of ice slurry flowing in horizontal pipes, at same time analyzed the effects of flow and ice packing fraction on heat transfer of fan and coil

在传统液固两相流的研究成果基础上，建立起二元冰在水平管内换热的数学模型，同时针对二元冰在风机盘管中的输送情况，分析了输送速度、含冰率对于二元冰换热的影响

Proposes a new method to calculate the heat transfer coefficients based on the superposition principle of heat flux i.e.using heat flux to calculate equivalent heat transfer coefficients.

通过对热流相加法处理地面问题的分析，提出了一种新的用于计算底层地面传热系数的方法，即由热流量计算地面的当量传热系数。

In addition, the computational evaluations indicate that the heat transfer enhancement of delta winglet for aligned tube bank heat exchanger is more significant than that for staggered tube bank heat exchanger, the heat transfer enhancement of delta winglet with the attack angle of 45° is more obvious than that of 30°; the delta winglet with the attack angle of 45° leads to an increase in pressure drop, while the delta winglet with the attack angle of 30° results in a slight decrease.

另外计算还发现：三角形小翼对顺排换热器的强化换热效果好于对叉排换热器的强化；冲角为45°的三角形小翼强化换热效果好于冲角为30°的三角形小翼；冲角为45°的三角形小翼导致空气压降提高，而冲角为30°的三角形小翼则可使压降有所减小。

The distribution uniformity of external magnetic field is weakened by the cylindrical coil with some thickness ferric-core. The model of fluid flow and heat transfer of spot GTAW pool in longitude magnetic field controlling is developed for the first time, which incorporates the free surface, surface tension gradient, additional fluid drive forces owing to the external longitude magnetic, heat transfer between weld pool and medium, latent heat of solid/liquid phase and heat physical properties of materials.

综合考虑了焊接熔池表面张力温度系数的变化、熔池自由表面变形、外加纵向磁场对熔池流体的附加作用力、熔池与周围介质的换热、固/液两相区的熔化潜热、焊接材料的热物理性能等问题，将熔池自由表面变形、外加纵向磁场与熔池流场的计算过程相耦合同时进行分析，模拟了不同焊接材料、不同外加磁场以及不同焊接条件下外加纵向磁场GTAW定点焊接熔池流体流动与传热过程。

Firstly, the mechanism of heat transfer enhancement by oscillation heat surface is discussed in natural convection scene. For different oscillation amplitude and Rayleigh number, the frequency that the heat transfer rate of oscillation heat surface is higher than non-oscillation condition is found and called critical oscillation frequency. The limitation enhancement of similar physical model is still researched by this study in mixed and forced convection scenes for different amplitude and Grashof number.

首先探讨在垂直管道内振动高温面於自然对流领域内提升高温面热传效率的机制，并且针对不同的振幅与雷利数求得加入振动条件后，高温面散热效果可以优於稳态非振动高温面散热效果的临界振动频率；进而探讨当垂直管道流进入混合对流与强制对流范围时，在不同的振幅与葛瑞秀夫数下，亦可发现加入振动条件后，振动高温面之散热效果可以优於稳态非振动高温面散热效果的临界振动频率。

And the pressure drop of liquid-layer is mainly influenced by weir height. With the increasing of weir height, the pressure drop increases. And it is independent of bare tower velocity and plate dimension. The correlation before was corrected as follows:ΔpL＝3911Z This paper analyzed the heat transfer coefficient between the outer wall of heat tubes and cooling water. And it was considered that plate geometries、weir height、bare tower velocity and heat flux density would affect the heat transfer coefficient.

而液层阻力主要受堰高的影响，堰高越高，液层阻力越大，与空塔速度和孔板的几何尺寸无关，对以往的公式进行修正后得到实验关联式如下：ΔpL＝3911Z 本文对加热管外壁与冷却水之间的换热系数进行了分析，认为孔板的几何尺寸、堰高、空塔速度以及热流密度均会影响换热系数。

The invention is suitable for pipe shell type heat exchanger, better heat transfer effect can be achieved by adopting the arrangement method for heat transfer pipe according to the invention, and heat exchanger having different temperature difference of intake water and outtake water can be conveniently combined.

本发明适用于管壳式换热器，在换热装置中采用本发明的传热管的排列方法，可以达到较好的传热效果，而且可以方便地组合成不同进、出水温差的换热器。

The association effect of inert gas and gas phase acetic acid-water in condensing process was considered, the heat and mass transfer behavior of the heat exchangers at every step and the influence of heat and mass transfer on the design of heat exchangers were analyzed for the condensing process of acetic acid, water, and mixed nitrogen vapor in the condenser in the PTA oxidation process.

针对PTA氧化反应中冷凝器内的醋酸、水和氮气混合蒸气冷凝过程，考虑冷凝过程中惰性气体和气相醋酸-水缔合效应，分析了各级换热器内传热传质行为以及传递对换热器设计的影响。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。