Intercomparison of Numerical Urban Dispersion Models – Part I: Street Canyon and Single Building Configurations

Microscale Computational Fluid Dynamics (CFD) models havebecome an efficient and common simulation tool forassessment and prediction of air quality in urban areas.The proper validation of such a model is a crucialprerequisite for its practical application. Within theframework of the European research network TRAPOS a workinggroup on computational fluid dynamics modelling wasestablished and model intercomparison exercises werelaunched. Different Computational Fluid Dynamics Codes wereapplied for simulating the wind flow and pollutantconcentration patterns in several test cases. The aim ofthe present model intercomparison is (1) to assess andallocate the source of differences that appear whendifferent CFD codes using the same turbulence model areapplied to well defined test cases and (2) to improve theknowledge base for model development and application.Throughout the series of model applications coveringmanifold urban configurations, the overall agreementbetween the various models and experimental data is fair.In spite of quantitative differences between the variousnumerical results, the models are capable of reproducingthe flow patterns and dispersion characteristics observedin urban areas but they show significant differences forthe turbulent kinetic energy field that controls thedispersion of pollutants.     

钻屑、钻井液固化处理及对环境的影响分析

钻屑和废钻井液的固化处理是现阶段钻井废物无害化处理的主要研究方向,研究利用固化剂对钻屑和废泥浆进行固化处理,优选配方(水泥+粉煤灰+添加剂)进行固化处理;同时考查了钻屑、钻井液固化填埋后对周围环境的影响。结果表明,固化物浸出液的分析结果符合国家危险废物鉴别标准(GB5085.3-1996)和国家污水综合排放标准(GB8978-1996),对周围环境水质调查监测,环境水质未受到污染,与填埋前的监测指标变化不大。     

化学氧化—混凝沉淀法处理油田作业废液

采用化学氧化—混凝沉淀法对油田作业废液进行处理,筛选出最佳的混凝条件及氧化条件。实验结果表明,与产出水混合处理后可使原水的悬浮物从500～1000 mg/L降至<3 mg/L、总铁<0.5 mg/L。处理后的污水由处理前的黑浆状变为清澈透明,淡黄色,基本达到了注水水质标准。该方法具有投资小、净化效果好、设备简单、占地面积小、操作方便、不产生二次污染等优点。     

石油加工与石油化工废料应用于钻井液

石油加工与石油化工废料，包括废白土、酸渣、碱渣、渣油、油泥、生产润滑油添加剂的废料、废催化剂、环烷酸釜残等，在钻井液中的用途较广，可以分别用作钻井液原始组分和润滑剂、消泡剂、多效防塌剂、抑制剂、稳定剂、废钻井液固化剂以及制备这些处理剂的基础材料。文中介绍了前苏联及独联体等在这方面的研究成果和现场应用情况。     

水平地震激励下储罐液体晃动分析

在考虑地基与储罐相互作用的情况下，采用有限元法对储罐在水平地震荷载作用下的液体晃动反应进行了分析。结果表明：罐内液体的晃动是长周期运动，并且是多阶振型的组合。从与小体积罐的比较可以看出，大型储液罐的液面晃动不只是以基本振型为主，前几阶振型对液面晃动的贡献也比较显著，并且液面晃动的基本周期比小体积罐的大很多。     

废油基钻井液处理及油回收技术研究

目前现场处理废油基钻井液一般采用集中填埋或回注地层方法,这不仅难以解决其污染问题,同时也浪费了其中所含有的大量柴油资源。通过大量的实验室和现场试验研究,使用“化学热洗-析油-离心”处理工艺,油回收率达到84%以上;研制开发出的清油剂-凝聚剂-絮凝剂化学热洗配方体系,适用于多种废油基钻井液的回收油处理,具有较好的工业推广应用前景。     

Sustainable oil-in-water analysis using a supercritical fluid carbon dioxide extraction system directly interfaced with infrared spectroscopy

A direct aqueous supercritical fluid extraction (SFE) system using carbon dioxide provides a sustainable means by which a vast range of industries may continue to depend on well established infrared (IR) techniques to determine oil-in-water. The SFE-IR method provides an environmentally friendly substitute for current national standard IR reference methods for measuring oil-in-water that rely on using increasingly restricted ozone depleting solvents whose manufacture is being phased out in accordance with international law. The SFE-IR analysis of a 500 mL water sample can be accomplished in 15 min. A rapid on-line SFE-IR calibration method has been implemented. With this calibration method, SFE-IR accuracy for determining diesel oil in 500 mL spiked water samples using single wave number measurement was 86.0%–98.8% with precision (RSD) ranging from 2.5%–7.0%. Using a general purpose calculation which involves measuring infrared absorbance values at three di erent wave numbers, SFE-IR method accuracy for determining diesel oil in 500 mL spiked water samples was 83.7%–92.2% with RSD 1.0%–9.3%. Data is presented that indicates current long established national standard IR reference methods involving three wave number calculations should be reviewed since, without careful consideration, the inclusion of calculated aromatic hydrocarbon species contributions to final oil-in-water concentration values may provide less accurate results.     

氧化沟流场的计算流体力学数值模型研究

该研究发展了氧化沟计算流体力学模型。采用三维标准k-ε湍流计算流体力学模型对全尺度氧化沟进行了数值模拟和试验验证,并用动量源项方法描述倒伞曝气机对氧化沟中流体的驱动作用,试验结果和模拟计算间良好的一致性证明了模型的合理性。模拟和试验均发现大量低流速区域的存在,尤其是表面曝气机下部靠近沟底的区域,有必要改善氧化沟的水力学性能。同时,对网格独立性进行了验证,比较了不同湍流模型的计算结果。     

超临界CO_2流体环境中线路板的热分析

在无氧环境中,当温度加热到300℃以上时,线路板中的粘接材料(溴化环氧树脂)就会发生热解反应,这是利用热解法回收废旧线路板的理论依据.在超临界CO2流体环境中,当温度达到260℃时,线路板中的环氧树脂也会发生不完全热解反应.本文建立了高温高压下线路板的热分析模型,并对线路板内部的热应力进行研究,发现其对整个反应过程起到了一定的推动作用.     

汤参-井水氡异常特征研究

汤参-井水氡2008年度出现明显异常,本文进行了深入地分析研究。通过对比研究该井其他测项以及与其相邻的台站水氡资料,发现其他测项没有出现与汤参-井水氡同步大幅度异常,排除了汤参-井地下地应力显著改变的可能性,认为汤参-井水氡异常主要原因是由于其周围大量的地热井开采导致汤参-井地下水在流出地面越来越慢所致。