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1.
以氨-水溶液为工质的制冷/制热潜能储存系统特性研究   总被引:2,自引:1,他引:2  
介绍了以氨-水为工作介质的制冷/制热潜能储存工作循环和流程;根据工作循环的特点提出了循环的计算方法,并对工作循环进行了详细的计算和分析。可以发现,以氨-水为工作介质的制冷/制热潜能储存系统具有较广的工作范围,不仅可用于蓄能空调系统,还可用于0℃以下的蓄能制冷。根据不同的需要,工作溶液的蓄能密度可以在较大的范围内改变。最大的蓄能密度可以超过冰蓄冷,但其代价是降低了系统的COP值。  相似文献   

2.
采用溴化锂溶液的蓄能空调/供热系统及其数学模型   总被引:1,自引:0,他引:1  
利用工作溶液浓度差储存的能量可转换成暖通、空调所需的热能、冷能或除湿能.以工作溶液为澳化锂水溶液时的闭式蓄能空调/供热系统为研究对象,通过阐述其工作原理和运行过程中储罐内溶液质量、质量分数、温度等参数随时变化,导致系统内各状态点溶液工作参数、各热力设备的工作负荷均发生变化的特点,建立起该蓄能系统充、释能过程的动态数学模型.其结果可为进一步数值研究、分析该蓄能空调/供热系统工作特性、设备负荷特性提供参考.  相似文献   

3.
溴化锂溶液蓄能空调/供热系统工作特性模拟与分析   总被引:1,自引:0,他引:1  
在所建立的系统运行动态数学模型基础上,针对具体应用实例对以溴化锂溶液为工作介质的蓄能系统进行数值模拟.以长江流域某城市一宾馆建筑为例,在设计日室外温度变化范围为29~38℃.空调最大冷负荷为1 450 kW.日需冷量为19 890 kwh.日需50℃洗浴用热水20t(720 kWh)条件下,分别对蓄能空调/供热系统在全量和分量蓄能策略下的工作情况进行数值模拟.分别得到了蓄能空调/供热系统所需的澳化锂溶液充注量、储罐容积、溶液 参数、设备负荷变化等重要基础数据及变化规律.这些数据和变化规律是先进蓄能空调/供热系统设计、控制、技术经济评价、设备选型或设计等工作的基础.  相似文献   

4.
余热蓄能系统应用在分布式冷热电三联供(CCHP)系统中,可以有效改善系统性能,提高系统节能率。针对CCHP系统对蓄能系统的要求,该文设计搭建了最大功率30 k W溴化锂吸收式蓄能实验系统。该系统能够测试不同冷热源条件下,蓄能系统的特性(输入特性以及输出特性)。实验结果显示系统运行稳定,说明这一技术路线可行,满足实际系统蓄能需要;同时蓄能装置的实际蓄能密度达到90 k W·h/m~3,有效蓄能利用系数达到了0.5以上,达到了该领域的先进水平。  相似文献   

5.
蓄能型太阳能溶液除湿蒸发冷却空调系统研究   总被引:11,自引:0,他引:11  
以实验的方法对采用填料塔式再生器的溶液除湿蒸发冷却空调系统的再生性能进行研究,得出了再生器热源温度在55.5 ℃工况下的传质系数和热源温度对出口参数有影响的结论.同时发现传质系数平均值约为0.32 mg/(m2·Pa·s),根据实验数据提出提高填料塔式再生器再生性能的方法.同时提出一种蓄能密度高的相变潜能蓄能模式,并在理论上对其进行定量分析,结果表明该种蓄能模式的蓄能密度一般在1 000 MJ/m3以上,这表明该蓄能方法比常规蓄能方法更为有效.  相似文献   

6.
高温双再生器型吸收式热变换器热力循环分析   总被引:1,自引:0,他引:1  
提出一种新型以溴化锂溶液为工质的高温双再生器型吸收式热变换器(HDAHT)循环系统,该系统在高温单级吸收式热变换器循环中再生器和冷凝器之间增加了第二级再生器.HDAHT系统可以将高温废热源的温度进一步提高至有用温位.对HDAHT内各参数对系统性能系数COP的影响进行了模拟计算.计算结果表明,系统性能系数COP随着蒸发温度、低压再生器温度和溴化锂溶液中间浓度的升高而增大,随着吸收温度、高压再生器温度和溴化锂稀溶液浓度的升高而减小.在适合的操作条件下,本循环的系统性能系数COP达到了0.61,是高温单级吸收式热变换器的1.2倍.所得到的这些规律将为高温吸收式热变换器设计系统优化提供必要的理论依据.  相似文献   

7.
针对吸收式太阳能海水淡化系统,设计了一套竖管降膜吸收实验装置,以溴化锂溶液为工质对装置进行了实验研究.通过改变水和溶液温度、喷淋量及溶液的浓度,测试了不同工况下系统的运行情况,得出溶液具有较好吸收率的基本条件,给出了系统最佳运行的参数范围.实验表明,在运行压力达到10 kPa和溶液浓度为50%左右的情况下,当被吸收水的温度高于30℃时,溶液已有较好的吸收速率,此时热源的温度仅为45℃~55℃,这十分有利于太阳能集热系统发挥供热效率.  相似文献   

8.
氨-水和氨-水-溴化锂在吸收式制冷机中的对比实验研究   总被引:4,自引:3,他引:1  
通过吸收式制冷实验,对比研究了溴化锂对于氨水吸收式系统性能的影响,包括浓溶液发生过程气-液相平衡特性和系统性能系数的变化.测定了氨-水-溴化锂三元吸收式系统发生过程中的温度-压力关系,计算了系统的性能系数.温度范围从15℃到80℃,压力达1.5 MPa.实验采用了3组溶液:A(X(NH3)=48%),B(X(NH3)=51.8%,X(LiBr)=42%),C(X(NH3)=58.7%,X(LiBr)=42%).对比发现,溶液B、C的发生压力分别比相同氨含量的二元溶液下降了约21%和30%,且发生温度越高,发生压力降幅就越大.采用溶液A时系统的性能系数为0.242,而采用溶液B、C时性能系数分别为0.293和0.334,分别提高了17.2%和33.6%.因此,在氨水吸收式制冷机中加入溴化锂可以明显提高机组的性能系数.  相似文献   

9.
溴化锂空调可利用海上平台透平机组的高温烟气实现无能耗的制冷、制热,并能提供卫生热水,不仅可以实现节能减排的目标,还可以降低烟气排放温度。以绥中36-1CEP海上石油平台为例,介绍了透平机组和各需要改造区域的现状,结合溴化锂机组的特点,从主机安装、烟气系统、冷却水系统、空调水系统、淡水系统及其余系统几个方面分析了溴化锂空调替代电中央空调的设计方案,从而确定绥中36-1CEP平台溴化锂空调替代电中央空调在技术上是可行的。  相似文献   

10.
太阳能作为一种新能源,是一种清洁无污染的可再生能源。太阳能热水系统是以吸收太阳辐射能为热源,将太阳能转为热能以达到加热水的目的的整套装置,包括太阳能集热装置、储热装置、循环管路装置等。由于太阳能热水系统在全年运行中受天气的影响很大,其独立应用存在间歇性、不稳定性和地区差异性,在太阳能应用中除利用集热器将太阳能转换成热能外,应采取热水保障系统(辅助加热系统)和储热措施来确保太阳能热水系统全天候稳定供应热水。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

17.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

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