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1.
奥里油燃烧后的排放物温度以及SO2浓度比较大,为了对电厂周围环境质量进行分析,采用CFD软件进行模拟。模拟了奥里油电厂高架连续点源的烟羽传输与扩散, 根据湛江市有代表性的年平均气象数据,采用Fluent软件分析了不同大气风速和湍流度下奥里油电厂烟羽传输与扩散的特殊规律, 给出了描述大气污染的两个重要参数最大落地浓度及离源距离和烟羽中心线抬升高度及离源距离的下风向沿程变化情况。数值计算结果与烟气扩散理论和经验数据是相符合的, 所以该模型可以较好的模拟奥里油电厂烟羽的传输与扩散的特殊性,从而为该电厂的环境影响评价提供依据。  相似文献   

2.
湿烟气由烟囱出口进入温度较低的环境空气会形成湿烟羽现象,产生视觉污染。分析了湿烟羽的形成机理和消散技术,采用数值计算研究了不同湿烟羽消散技术的特点。结果表明,烟气直接加热、烟气直接降温和烟气降温再热可以消散湿烟羽;烟气降温再热消散湿烟羽使用范围最大,烟气直接加热次之,烟气直接降温最小;环境温度低于10℃,环境相对湿度大于40%时,烟气直接加热和烟气直接降温消散湿烟羽的升温幅度和降温幅度较大,湿烟羽消散难度大;环境温度低于5℃时,只能采用烟气降温再热消散湿烟羽。  相似文献   

3.
对稳定线性热分层环境下湍浮力羽流无量纲积分方程首次采用数值解法进行求解,得出浮力通量、动量通量等参量在轴线上的变化规律以及羽流中性浮力点的高度和羽流最大上升高度。2种不同尺度空间及不同烟气羽流出口条件的实验表明,实际火灾烟气羽流最大上升高度与理论计算结果及文献经验公式相符,从而表明积分模型数值解的有效性,并为高大空间火灾烟气输运规律研究及探测技术发展提供了理论及实验依据。  相似文献   

4.
针对因缺乏实际环境因素的考虑而对二氧化氮气体扩散预测不准确的问题,提出可引入降雨量与地形来对气体扩散进行一定的研究分析。以原有高斯烟羽模型为基础,引入雨强以及粗糙度分别代表降雨量与地形来进行改进并进行数值模拟分析。通过对比分析,首先模拟了在同一高度下不同雨强以及不同粗糙度单独对气体扩散的影响;然后再从分别通过对下风向、横风向与气体浓度之间的关系对比;最后,将粗糙度与雨强同时作用并将结果与原模型进行对比分析。根据实验结果发现:降雨量和地势影响了在一定高度上气体扩散浓度值以及扩散范围,对比起传统的高斯烟羽模型,此模拟结果更符合实际。  相似文献   

5.
为了更好发挥发烟装备的使用效果,需要研究风速标准差对烟幕扩散的影响规律.通过分析现场观测数据,研究了稳定、中性层结条件下3个方向风速分量标准差与稳定度分类判据SR数及平均风速之间的关系,运用高斯烟羽模式结合实测平均风速和风速标准差计算了烟幕在大气中的扩散效果,分析了平均风速和风速标准差对烟幕有效遮蔽区域长度、高度、面积的影响规律.结果表明,烟幕有效遮蔽区域长度和高度的主导因素分别为垂直方向风速标准差和平均风速;相同的稳定度类别和近似的平均风速条件下,风速分量标准差可能存在较大差别,导致烟幕有效遮蔽区域的长度和面积可能存在量级上的变化.因此,在发烟装备评价和使用过程中,观测并参考风速标准差是很有必要的.  相似文献   

6.
井口抬升高度对高温气井管柱设计、固井设计以及地面管线设计等至关重要,但套管性能、自由段长度等因素对井口抬升高度影响显著。为阐明井口抬升机理,分析套管性能对井口抬升高度的影响,充分考虑温度对套管力学性能的影响,建立多因素作用下井口抬升高度预测模型,并分析受温度变化影响抬升高度的关键因素。利用文昌气田X井测试管柱实测数据分析不同情况下套管热膨胀系数和弹性模量对抬升高度的影响。结果表明:同时考虑热膨胀系数和弹性模量共同作用的预测模型对井口抬升高度影响最大,与现场实际最为接近,应作为工程分析的首选。研究结果对井口抬升高度预测及油气井安全生产具有重要的指导意义。  相似文献   

7.
增压锅炉过热器强化传热机理及热力计算方法研究   总被引:1,自引:0,他引:1  
利用热工基本原理分析了一定压力下烟气和过热器管束对流传热的机理,探讨适合于增压锅炉过热器的热力计算方法.根据质量守恒定律,通过烟气喷量流速uρ来计算Re数,进而计算烟气对流放热系数,从而避免了对烟气运动黏度ν的考虑.应用所选择的公式对某型增压锅炉进行了计算,计算结果和实际运行数据相吻合。  相似文献   

8.
高水分烟气辐射换热实验研究   总被引:2,自引:0,他引:2  
为克服垃圾中水分含量偏高,燃烧时传热特性与常规燃料存在较大差异的问题,根据热平衡原理,对高水分烟气的辐射换热特性进行了实验研究。进行了对管内径105,150,208mm,烟气温度300~800℃,水蒸汽份额20%~50%的126个工况的实验。结果表明,在高水分条件下,烟气的辐射换热性能显著增强,原有锅炉计算的标准方法已不再适用。考虑到水蒸汽含量的影响,对原有计算公式中的烟气辐射减弱系数进行了修正,得到一种工程上简便实用的计算方法,可满足垃圾焚烧锅炉设计的需要。  相似文献   

9.
苑鑫 《山西科技》2014,(6):154-155
分析了嘉乐泉煤矿热风炉烟气治理工程实施前后烟气排放情况,提出了包含二氧化硫排放浓度、烟尘排放浓度以及烟气黑度等因素在内的评价体系,并采用该评价体系对嘉乐泉煤矿热风炉烟气治理效果进行了初步评价,最后根据评价结果提出了进一步提高烟气处理效果的思路和方法。  相似文献   

10.
针对布里吉斯公式不能同时准确计算烟云抬升高度和烟云扩散率的缺陷,通过分析布里吉斯公式的基础假设及其推导过程,提出一个修正初始半径,并用它对布里吉斯公式的初始条件进行修正.修正后的布里吉斯公式可以同时准确计算烟云抬升路径和烟云扩散率,从而提高了布里吉斯公式的通用性.  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 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   

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.
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   

15.
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   

16.
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   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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