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1.
对采用电加热、并联式及串联式回收冷凝热3种再热方式的恒温恒湿空调机组运行特性进行试验研究,分析讨论了设定不同温、湿度值对3种再热方式控制精度的影响,对3种再热方式的功耗进行了对比分析.试验分析表明:电加热是温、湿度控制精度最高、耗能最高的一种再热方式;与采用冷凝热回收系统相比,采用电加热方式的恒温、恒湿空调机组能耗降低30%左右,是一种节能的再热方式,并联式系统的功耗略低于串联式系统;当并联式冷凝热回收系统设定的温度为18~28℃、相对湿度在45%~70%的范围内时,温度和相对湿度的控制精度可以达到士1.0℃和±8%;对于串联式系统,当设定温度低于18℃时,系统控制存在盲点,但当设定温度升高至23℃后,机组控制精度明显提高,控制精度高于并联式系统.  相似文献   

2.
设计了一种新型气液分离式管内凝结冷凝器,对该冷凝器进行了实验测试,并与卧式壳管式冷凝器进行了对比分析.研究结果表明:在质量流量为220~330kg/h,饱和温度为35℃、40℃和45℃时,气液分离式管内凝结冷凝器的传热系数线性增大.在高质量流量下,其传热性能明显优于卧式壳管式冷凝器.实验条件范围内,采用气液分离式管内凝结冷凝器的系统比采用卧式壳管式冷凝器的系统制冷剂的出、入口压降降低了45.1%~50.7%,排气压力提高了约1.9%,COP提高了5.0%~9.3%.气液分离式管内凝结冷凝器具有更好的换热性能,有效提高了系统的效率.  相似文献   

3.
以广州地区的办公建筑为例,就一次回风集中空调系统在空气处理过程中采用热管式空调机组时,不同室内设计温度下的空调系统能耗进行了分析,并且与常规的一次回风集中空调系统的耗能量进行了比较.研究结果表明:在相同的室内设计温度下,采用热管式空调机组处理空气的一次回风集中空调系统比常规的一次回风集中空调系统节省冷量和再热量.节能效果随着室内设计温度的提高而提高.在通常的室内设计温度22~26℃范围内,相应的冷量节能率为24.3%~25.8%,总耗能量的节能率为39.1%~41.0%.  相似文献   

4.
针对纯电动汽车设计了一套带有废热回收的热泵空调系统,采用2个分回路吸收电池和电机产生的废热,分析了电池和电机废热量产生规律以及对废热回收系统进行了整车试验.结果表明:纯电动汽车在车速变化时,电池散热量迅速增加,即废热增加;当废热回收热泵系统在2℃的工况下运行时,换热量最大可增加至3 797 W,能效比范围为1.82~2.43,增加的废热能满足制热要求;当温度降到-7℃时,换热量最大可增至2 407 W,能效比范围为1.56~2.63,回风温度可达13.2℃,但仍需提供额外热源才能满足制热要求.  相似文献   

5.
为了得到地板送风系统理想的送风参数,首先通过正交实验研究不同送风参数对地板送风系统房间温度分布、热舒适性和空气品质的影响,然后采用控制变量法进一步研究送风温度和速度对系统性能的影响,最终通过Energy Plus能耗模拟软件计算得到供冷工况下热分层良好、舒适性较好且能耗较低的理想送风参数.实验结果表明:当旋流风口到人体的距离为0.7 m,送风温度为18~20℃,送风速度在1.2~1.5 m/s时,室内热分层较好,能够满足人员热舒适性和空气品质的需求.对不同送风参数下运行特性与能耗影响的模拟计算表明:在理想送风参数范围内,当送风温度为18℃、送风速度为1.2 m/s时,地板送风系统不仅可以保持较好的热舒适性和良好的热分层,同时还具有较低的能耗.  相似文献   

6.
以吉林省敦化市为例,根据采暖期室外气温实际情况,对空气源热泵在严寒地区低温条件下供暖情况进行应用研究.在综合考虑空气源热泵结霜、除霜和低温环境下制热量情况下,对运行能耗、费用、回收年限进行分析.得出室外采暖计算温度为-20℃,且室外气温低于-15℃的时数占绝大多数的地区,采用超低低温空气源热泵机组时,可以实现全供暖期高效运行.  相似文献   

7.
研究了余热回收技术在-10,-5,0℃下电池包加热的性能差异,并与传统加热方式进行了热管理性能和能耗的对比分析。基于国内某款商用电动车的整车热管理架构,提出了一种创新性的余热回收系统,能够显著降低热管理系统能耗。为此,基于一维热管理分析软件KULI,建立了余热回收模式下的电驱电控及电池包热管理系统模型,并建立了基于规则的控制策略,实现对散热风扇、冷却水泵、电控比例阀和四通道电磁阀的控制。仿真结果表明,在低温环境中,余热回收系统能够降低电池包用于加热自身的能耗,同时充分利用电驱电控系统产生的废热。根据仿真结果,电池包从环境温度-10,-5,0℃加热电池包到15℃,与传统加热方式热管理系统相比所消耗的能耗分别降低209.5,406.4,460.0 kJ。  相似文献   

8.
介绍了压力仪表温度系数测量系统的组成、结构和原理,系统由恒温箱系统和压力测量系统二大部分组成,在-40℃~+70℃ 温度范围内能够稳定在任意温度上,压力测量范围为(0~60)MPa.系统具备了较好的恒温和压力测量技术性能,通过实验证明了其能够用于压力仪表温度系数的实时测量,可实现压力仪表温度适应性性能的准确评价.  相似文献   

9.
研究了合成致密刚玉-莫来石-锌铝尖晶石复相材料的工艺条件.通过XRD和SEM分析了煅烧温度与生成物相的关系,采用二步煅烧工艺研究了轻烧温度及轻烧时间对刚玉-莫来石-锌铝尖晶石复相材料的烧结性能的影响.结果发现:采用ZnO、SiO2、Al(OH)3为原料,1300℃时,系统中能够生成刚玉、莫来石、锌铝尖晶石.在轻烧温度为1300℃时,最佳的保温时间为3h,此时显气孔率达到最小,体积密度相应最大.进一步提高轻烧温度到1400℃时,有利于刚玉-莫来石-锌铝尖晶石复相材料的烧结,在此轻烧温度下,最佳的保温度为2h,此时试样的显气孔率达到最大,体积密度相应最小.  相似文献   

10.
针对多路温度同步测量的需求,研制了一种基于可编程逻辑阵列(field program gate array,FPGA)和低功耗内核(STM32)的多路温度同步测量系统。该系统以FPGA为主控制器,直接驱动多片模数转换器件,对多路电信号进行同步测量,使用STM32实现温度信号的转换和计算。系统预期测温范围为-200~850℃,测温精度达到0.01℃。实验结果表明,该系统在使用PT100温度传感器测温且测温范围为-200~400℃时,系统测量误差小于0.003℃,全量程(-200~850℃)范围内系统测量误差小于0.005℃。所设计的多路温度同步测量系统尽管随温度增大测量误差存在增大趋势,但在全量程范围内实现了0.01℃测温精度的目标,并具有多路温度同步测量、通道数易于扩展等优点,具有一定的实用价值。  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

17.
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   

18.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  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.
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