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1.
为了检验公路卧铺客车四风道空调系统的热舒适效果,按照相关标准的要求,采用风速仪、K型热电偶和数据采集器等仪器,对空调系统的送风参数和车内的温度分布进行了试验研究。结果表明:车内各送风口的送风速度和温度存在明显的差异,均匀性较差,车内气流难以有效组织;从车内总体温度分布而言,纵向呈现出前后端温度高、中间温度相对较低的特点;左侧下铺的平均温度要高于其他铺位的平均温度;车内整体温度不均匀程度高,且平均温度较低,不能满足人体的热舒适性要求。  相似文献   

2.
人体舒适度与室内热环境   总被引:2,自引:0,他引:2  
通过对自然通风环境、实际空调环境、实验空调环境与人体舒适度的关系的分析,发现在自然通风条件下人体热感觉随着温度变化是最小的,仅为0.0949(TSV)/℃,而在实际空调环境下,热感觉与温度关系最大,变化率为0.3245(TSV)/℃.说明在自然通风条件下,影响人体突然感觉的其他因素比实际空调环境以及实验空调环境的要多;本文对三种热环境下热不可接受率与实测不舒适度进行比较,发现实测不舒适度远高于热不可接受率,说明热感觉并不等同于热舒适;在自然通风环境下,高温高湿(28℃,80%以上)条件下,空气焓值大小对实测不舒适度的影响比温度、相对湿度更为明显.  相似文献   

3.
目的研究现有火墙式火炕基础上增加集热器的火墙式低碳节能火炕,改善农村的环境,解决北方农村冬季采暖现状.方法分别将集热器放置于火炕和火墙内,测量实验数据.结果通过对炕面温度、火炕烟道温度、室内温度、集热器进出口水温等参数的测试,分析集热器与烟气或火焰换热的主要方式,分析增加了集热器的火墙式火炕降低炕前端过热温度、改善炕面受热不均、提高室内热舒适度以及增强火炕自身蓄热能力的节能特性,并与现有的火墙式火炕进行综合分析对比.增加集热器的火墙式火炕前端温度较普通的火墙式火炕降低了20℃,炕表面平均温度降低了8℃,室内温度升高了2℃,停火后增加集热器的火墙式火炕在12 h后将恢复室温,相同条件下比火墙式火炕延长2 h.结论新型的增加集热器的火墙式火炕具有炕面温度均匀、蓄热能力强、室内舒适度增加等特性,在节能环保领域具有重要的应用和推广价值.  相似文献   

4.
采用试验和数值仿真方法分析研究了地板辐射供暖室内舒适性。研究结果表明:随着进水温度不断提高,室内温度呈现上升趋势,在竖直方向温度出现分层现象,且室内温度分布的实验值略低于模拟值;针对进水为45℃、50℃、55℃3种不同工况,结合室内温度分布、PMV-PPD指标以及室内速度分布状况分析可知,进水为50℃时室内具有最佳的温度与热舒适度;对于3种工况下的室内空气流动状况,均在人体可接受范围以内,对室内热舒适性影响较小。  相似文献   

5.
采用试验和数值仿真方法分析研究了地板辐射供暖室内舒适性。研究结果表明:随着进水温度不断提高,室内温度呈现上升趋势,在竖直方向温度出现分层现象,且室内温度分布的实验值略低于模拟值;针对进水为45℃、50℃、55℃3种不同工况,结合室内温度分布、PMV-PPD指标以及室内速度分布状况分析可知,进水为50℃时室内具有最佳的温度与热舒适度;对于3种工况下的室内空气流动状况,均在人体可接受范围以内,对室内热舒适性影响较小。  相似文献   

6.
目的分析杭州市气候舒适度的多年变化特征。方法运用气候舒适度分析方法,选用国家气象局规定的统一标准,计算分析了杭州市气候舒适度指数的变化情况。结果杭州市50年来平均温度呈上升趋势,平均相对湿度呈下降趋势,平均风速变化不明显。气候舒适度总体呈上升趋势;从不同等级气候舒适度天数变化来看,总体上表现为人体感觉冷不舒服的天数为减少的趋势;而人体感觉热不舒服的天数变化不明显;人体感觉舒服的天数也表现为增加趋势。结论气候变化对杭州的气候舒适度发展总体有利。  相似文献   

7.
以西北新农村117.07 m2的单体建筑太阳能采暖系统为研究对象,以12月15日为例,得出储热水箱热损失主要发生在自然冷却阶段,当日储热水箱的总热损系数为5.68 W/℃,总热量损失为9.49 MJ.再选取其余11个典型日的试验数据对储热水箱总热损系数和总热损失各影响因素进行拟合,储热水箱总热损失由于受到环境温度和室外风速的影响,储热水箱的温度也随之变化.研究结果表明:平均环境温度每降低1 ℃,储热水箱总热损失增加0.067 MJ;室外风速每增加1 m/s,储热水箱总热损失增加0.042 MJ;储热水箱平均温度每降低1 ℃,储热水箱总热损失增加0.068 MJ;储热水箱温度变化幅度每增加1 ℃,储热水箱总热损失增加1.641 MJ.针对储热水箱热损失分析及室内热环境现状,提出将储热水箱置于室内以增强储热水箱储热能力和改善建筑室内舒适度.  相似文献   

8.
针对人体正常鼻腔及病变鼻腔在高速气流下的流场温度进行研究,揭示高速气流下鼻腔温度调节特性。建立反映鼻腔壁面温度特征的分区鼻腔物理模型,根据模型特点提出数学方程并应用有限体积法进行离散推导,使用数值方法对物理模型进行仿真计算,探讨三种主要高速流量工况下正常鼻腔及病变鼻腔流场的温度场特性。仿真结果显示,三种高速气流下经人体正常鼻腔温度调节后气体平均温度为29℃~30.5℃,经病变鼻腔温度调节后气体平均温度为26℃~29℃。得到结论:高速气流下正常鼻腔和病变鼻腔的温度调节功能明显下降;通过实施入口条件的温度补偿,可以提高鼻腔温度调节后气体的温度。  相似文献   

9.
夏热冬冷地区在空调系统设计中一般以夏季工况为主,故可能造成冬季供暖能耗浪费且室内温度无法满足人体热舒适要求.针对上海一实际办公室在不同送风速度下对冬季室内热环境进行了实测.实测结果表明:夏热冬冷地区建筑窗墙面积比过大和送风参数的不当设置,使送风热量难以到达人员所在空间,导致室内上部与下部空间温差过大和加热过程中存在能源浪费.尽管提高送风速度不能彻底解决人体头-足温差过大的问题,但可以减小因温度分布不均匀造成的热负荷增加量,改善人体热舒适和实现节能效应.  相似文献   

10.
在由间歇排渣型锁斗和洗涤冷却室组成的模拟系统中,应用R ealizab leκ~ε湍流模型进行了非稳态计算,得到的计算结果和实际情况比较吻合。考察了多个因素对锁斗内平均温度的影响,模拟结果表明:锁斗循环水进口数对流场及温度场的分布影响较小;锁斗循环水量的影响很显著,循环水量越大,锁斗内湍流程度越剧烈,锁斗内平均温度越高;锁斗间歇排渣周期越长,锁斗内的平均温度越高;整个循环体系的热损失每增加0.5%,锁斗内的平均温度将下降5 K左右。  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.
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   

14.
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   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
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   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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