In order to solve the problems of helium convection inside hot gas conduit and abrupt pressure loss of hot gas conduit in accident condition, the present invention discloses one kind of convection and pressure loss preventing hot gas conduit, which includes from inside to outside the sectioned inside pipe, thermal insulation fiber layer and outer airtight cylinder. Between each section of inside pipe and the outer cylinder, there is one section of conic thin-wall pipe with one end welded to outer wall of the inside pipe and the other end to the inner wall of the outer cylinder for firmly connection and positioning.
为了解决热气导管内氦气对流问题，以及在事故工况下热气导管的突然失压问题，本发明公开了一种防对流和防失压的热气导管，由内至外包括分段的内管节、绝热层和气密的圆形外筒；在每段内管节与外筒之间设有一段圆锥形薄壁管，圆锥形薄壁管的一端与内管节外侧焊接，另一端与外筒的内侧焊接，使得每段内管节与外筒牢固连接并定位；所述每段内管节、薄壁管及外筒体之间均设有绝热纤维，从而形成绝热层；内管节之间设有供内管节自由热膨胀的间隙。
In different spray advance angle the predicted in-cylinder pressure curve can fit test curve well that proves the accuracy of the mathematic models involved in the multi-dimensional transient numerical simulation and the reliability of the application of whole model simulation. In addition the results show radiation heat transfer accounts for about 30%of the total heat transfer in diesel engine cylinder and heat transfer of piston accounts for 60%of the total heat loss.4.On the base of multi-dimensional transient numerical simulation of in-cylinder working process three dimensional coupled computation model which combines in-cylinder working process and combustion chamber components was built using partition solution method and boundary coupled method. So three dimensional complete model simulation by coupling in-cylinder working process and combustion chamber parts was realized and the effect of heat transfer space no-uniformity on in-cylinder heat transfer, flow, spray, combustion and emission is studied. Results show the effect of wall temperature space no-uniform distribution of combustion chamber components on heat transfer happens mainly at the end of compression stroke and expansion stroke. Therefore it can be concluded that wall temperature space no-uniform distribution of combustion chamber components would influence heat transfer during intake and exhaust stroke obviously. The wall temperature space no-uniform distribution of combustion chamber components is hardly related to in-cylinder gas flow, which is mainly dependent on the combustion chamber components structure, intake system structure, fuel spray nozzle structure, nozzle position and spray intensity. From the results of fuel atomization simulation it can be known the wall temperature space no-uniform distribution of combustion chamber components has certain influence on fuel atomization at the initial and middle stage of spray, mainly in the bottom space of combustion chamber and near cylinder wall. At the late stage of spray in-cylinder gas temperature is mainly dependent on fuel combustion, not on heat transfer of cylinder wall, so the wall temperature space no-uniform distribution of combustion chamber components has nearly no effect on spray. However at this time radiation heat transfer acts on spray remarkably that result in heat transfer increasing and spray getting worse. The heat transfer space no-uniformity of combustion chamber components has certain effect on CO_2 formation during spray and reduces gradually until late combustion stroke. For CO the situation is on the contrary. In addition radiation heat transfer influences the whole combustion process deeply. The heat transfer space non-uniformity of combustion chamber components directly influences the formation of NO_x and convection heat transfer space non-uniformity mainly influences the formation of NO_x near combustion chamber wall surface. The radiation heat transfer space non-uniformity mainly influences the formation of NO_x within combustion chamber space and not near the wall surface. The heat. transfer space non-uniformity of combustion chamber components has little effect on soot formation, far less than on NO_x.
在缸内工作过程多维瞬态数值模拟计算校验基础上，利用分区求解、边界耦合法建立了缸内工作过程与燃烧室部件的三维耦合计算模型，从而实现了缸内工作过程与燃烧室部件的耦合三维全仿真模拟计算，以此考察燃烧室部件传热空间非均匀性对缸内传热、流动、喷雾、燃烧和排放的影响，结果表明燃烧室部件壁面温度的空间非均匀分布对传热的影响主要是在压缩过程和膨胀过程后期，由此可推断在进气过程和排气过程中燃烧室部件表面温度分布的非均匀性对传热会有较为明显的影响；燃烧室部件壁面温度的空间非均匀分布对缸内气体流动几乎没有任何影响，缸内流动主要取决于燃烧室部件结构、进气系统部件结构以及喷油嘴结构、喷孔位置和喷射强度等；燃油的雾化效果的计算结果发现，喷雾初期和中期燃烧室部件壁面温度的空间非均匀分布对燃油的雾化有一定影响，主要影响燃烧室底部空间和壁面附近区域，在喷雾后期，此时缸内气体温度主要取决于燃油的燃烧，壁面换热的影响本身就极小，因此壁面温度分布的空间非均匀性对雾化的影响也极小，但辐射传热对燃油雾化效果会产生显著影响，换热量的增加使整体雾化效果下降；喷雾过程燃烧室部件传热空间非均匀性对燃烧产物CO_2的生成会产生一定影响，而燃烧过程后期这种影响逐渐减弱，其对中间产物CO的生成的影响则相反，另外，辐射换热对整个燃烧过程起到至关重要的决定性作用；燃烧室部件传热空间非均匀性影响最明显的是NO_x的生成，对流换热的空间非均匀性主要影响燃烧室壁面附件区域内NO_x的生成，辐射换热的空间非均匀性主要影响整个燃烧室空间内部NO_x的生成，在燃烧室部件壁面附件区域内的影响较小；燃烧室部件传热空间非均匀性对碳烟生成的影响要远远小于对NO_x生成的影响。
The absorption and release of latent heat, the heat loss by alloy elements vaporization, radiation, and natural convection are included in the solving conditions of the energyequation.
能量方程求解中考虑了固液相变潜热的吸收与释放；合金元素气化热损失、自然对流与辐射热损失；动量方程求解中考虑了热表面张力与浮力联合驱动流。
Analysis of notebook cooling natural convection and radiation intensity, the computer demand forced convection heat loss, through the analysis of board layout and heat transfer calculation to determine the heat pipe heat sink fan, as well as specifications.
分析笔记本自然对流和辐射散热强度，计算机内需强制对流散失的热量，通过分析主板布局和计算传热量，来决定热管风扇以及散热片的规格。
The flow field of cooling water in the body water-jacket, the heat convection coefficient of the inner wall, the cooling uniformity of each cylinder and the whole pressure loss for the original engine were analyzed.
对原机缸体冷却水套内冷却水的流场分布、冷却水套内壁面换热系数、各缸冷却均匀性和压力损失进行了分析。
An ideal impurity transport code has been used to simulate impurities (carbon and oxygen) behaviour during the OH discharge. The profiles of impurities diffusion and convection coefficient, impurities ion densities in different ionized state, loss power density and effective charge number have been derived.
建立完备的杂质输运程序，数值模拟碳、氧杂质在欧姆放电时的输运行为，得出了杂质的扩散和对流系数、不同电离态杂质离子密度、辐射功率密度和有效电荷数的空间分布。
The model considered the influences of the mode of reactants supply, the chemical reaction in the combustion chamber, radiation and convection heat loss of the combustion chamber wall, as well as fluid density changes in the tailpipe on stable operation of pulse combustion.
该模型考虑了反应物的供给方式、燃烧室内的化学反应、燃烧室壁面辐射与对流传热损失以及尾管内流体的密度变化对脉动燃烧稳定运行的影响。
The Level-Set approach was adopted to deal with some factors such as deposited track, liquid/vapor interface, which considered surface tension gradient (the major driving forces for the melt flow), interface curvatures, buoyancy and convection heat loss.
通过水平集（levelset）方法处理熔积轨迹、液/气界面等因素，考虑了熔体流动的主要驱动力表面张力梯度、表面曲率以及浮力等。
The result shows that heat loss of heat conduct, natural convection and heat radiation decrease the exergy efficiency of the thermoelectric device greatly.
结果显示，热传导损失、自然对流热损失和热辐射损失对太阳能热电装置的（？）效率有显著的负面影响。
The change in the radiation temperature gradient and the criterion of convection, and the enhancement of stellar wind and angular momentum loss.
辐射温度梯度变化，并引起对流判据变化；星风物质损失和角动量损失增大。
The thermal radiation, conduction and air convection of the calorimeter were analyzed, and its heat exchange equations were derived. The mathematical model of thermal loss of the calorimeter was established. The thermal loss in the process of temperature rising was compensated based on the model. The measurement repeatability error of the calorimeter for different input laser pulses was decreased from 4.7% to 0.6%, and the negative influence of thermal loss was removed.
由能量计热传导、热对流、热辐射的单位时间热交换方程推导出单位时间内能量计升温过程中热能损失的数学模型，根据数学模型对能量计整个升温过程的热损失进行补偿，使得能量计对于不同脉冲长度入射激光的测量结果重复性由4.7%提高到了0.6%，消除了能量计热损失给测量带来的不利影响。