制冷剂

Through simulating the cooling stage of a hanging water droplet and the temperature variation of cryogen droplets in cryogen spray, the model is validated by the reasonable agreement with the experimental measurements.

有关液滴初始参数对液滴蒸发冷却特性影响的研究结果表明，本模型可以为制冷剂喷雾冷却实际应用于激光治疗鲜红斑痣手术提供有效的分析方法。

It is found that there is a critical value (25mm) for the distance from the nozzle to the skin surface when the spray time is 40 ms. If the distance is too far or too near, heat extraction process will have different characteristics. The results could provide an applicable method for guiding the Cryogen Spray Cooling of laser therapy.

发现喷雾时间在40ms时，喷嘴到皮肤的距离具有一临界值（25mm），大于或小于此距离喷雾与皮肤的换热作用具有不同的特性，研究结果对于将制冷剂喷雾冷却实际应用于激光治疗鲜红斑痣手术具有重要的指导意义。

The system was reassembled using a new 4K GM cryocooler with larger cooling capacities both at the first stage and the second stage. The magnet reached a field of 5. 1T central field. This reassembled system was a cryogen free superconducting magnet system.

用一级和二级制冷量都较大的GM制冷机组成了第二套磁体系统，磁体中心场到了5T，既没有使用液氦，也没有使用液氮，这一套系统是最新式的无液体制冷剂的超导磁体系统。

After the DHX process was used on the light hydrocarbon unit to recover C3(superscript +) compound, it had a good result that the recovery rate of C2 compound was higher in the same operation conditions. And the liquid ethane could be used as the cryogen and absorbent to increase the recovery rate of C3(superscript +) compound and decrease the energy cost greatly at the same time.

以回收C3为目的轻烃装置采用DHX工艺（DHX塔闪蒸+脱乙烷塔分馏）后，在相同工况下能使C2获得更高冷凝率，并通过液态乙烷的制冷剂和吸收剂作用使C3收率大幅提高，达到节能降耗的同时也提高了C3收率。

The thesis can be divided into five parts as follows: First, the structural characteristics of finned-pipe evaporator are analyzed. After selecting suitable microelement controller, the heat-transfer and mass-transfer processes are analyzed for every microelement under the conditions of dryness, wetness and frostiness. Based on previous equations, some parameters of frostiness are confirmed and the frost-growing model is set up under frost condition. Some hypotheses are postulated and with the help of the equation of mass-conservation, energy-conservation and momentum-conservation, the evaporation model which fits in the dynamic simulation is built, which set a solid foundation for system simulation. Second, the starting and stopping behaviors under disturbed condition are analyzed and calculated by using the dynamic concentrative parameter model, which gives some advice to better prescribe refrigeration system and set theoretic foundation for carrying out automatic control of refrigeration system. Third, the normal running process is analyzed and calculated by means of rational matching theory, which gives some advice on how to better understand the parameter change under steady state and the affection of inlet-parameter on evaporator. Fourth, the simulation software with dynamic characteristic is designed, which can be applied to calculate thernio-parameter of cryogen, air humidity and frost thickness under different initial and boundary conditions, and to carry out dynamic simulation under conditions of dryness, wetness and frostiness, at the same time, to achieve detection and simulation at any stage from starting to stopping.

本文的主要内容如下：1对翅片管蒸发器结构特点进行分析，选取适当的微元控制体，就干、湿和霜工况下对每个微元分别进行传热传质分析，基于经验关系式确定霜的有关参数，对于霜工况下的霜生长建立模型，经适当假设，运用质量守恒、能量守恒和动量守恒方程建立适合动态仿真的蒸发器数学模型，为系统仿真奠定基础； 2对蒸发在大扰动下的开、停机过程，运用动态集中参数模型进行分析和计算，为更好地描述制冷系统运行的全过程奠定基础，同时也为制冷系统实现自动控制提供一定的理论基础； 3对蒸发器正常运行过程，运用动态分布参数和参数间定量耦合的观点来分析和计算，为更好地了解稳态工况下各点参数的变化情况及各入口参数对蒸发器动态特性的影响即蒸发器性能对各参数变化的敏感性； 4编写翅片管蒸发器动态特性仿真计算程序，可以计算不同边界条件和初始条件下的制冷剂热力参数、空气温湿度和霜厚度分布场，实现对翅片管蒸发器在干、湿和霜工况下的动态仿真。

An ozone layer depletion coefficient of zero has become absolutely essential for an advanced air conditioning system.

东芝在先进的空调系统中采用了不破坏臭氧层的、热效率更高的制冷剂。

Also, DuPont owns patents pertaining to R-407C in Europe and Japan, and in other countries as well.

同时，杜邦公司在欧洲、日本和其它国家拥有与 R-407C 制冷剂相关的专利权。

Coolant liquid after throttle valve expenditure of relief after a low-temperature low-voltage gas liquid mixed fluid, after separation into ammonia liquid separation devices for invalid after steam vaporizer, to evaporation endotherm.

制冷剂液体经过节流阀节流降压后成为低温低压的汽液混合流体，经过氨液分离器分离掉无效的蒸汽后供往蒸发器中蒸发吸热。

Coolant liquid after throttle valve expenditure of reliefafter a low-temperature low-voltage gas liquid mixed fluid, after separation into ammonia liquid separation devices for invalid after steam vaporizer, to evaporation endotherm.

制冷剂液体经过节流阀节流降压后成为低温低压的汽液混合流体，经过氨液分离器分离掉无效的蒸汽后供往蒸发器中蒸发吸热。

Whose concrete process is: The queen compression engine electrifying works , already endothermal low pressure , the low temperature gas state refrigerant suck to evaporating the implement inner in, as a result of compressing the queen, the temperature taking form is 55 ~C ~ 58 ~C, the intensity of pressure is 1128 the handkerchief high pressure , high temperature steam , entrance

其具体过程是：通电后压缩机工作，将蒸发器内已吸热的低压、低温气态制冷剂吸入，经压缩后，形成温度为55℃～58℃，压强为1128帕的高压、高温蒸气，进入冷凝器。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。