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1.
采用经典流体力学理论,以及计算流体力学(CFD)等方法相结合,对中缅油气 管线上具有代表性的岩鹰山隧道进行研究。用Fluent软件对岩鹰山隧道天然气管道泄漏 进行仿真模拟,利用Fluent模拟结果与泄漏源计算结果相结合,经过理论分析与数据拟 合,提出泄漏天然气充满隧道的时间计算模型,通过不同边界条件下隧道内天然气泄漏 扩散规律的模拟结果对时间模型进行验算并修正。利用计算流体力学(CFD)方法,研 究岩鹰山隧道在发生天然气泄漏事故后,单风机通风方案的效率,得出隧道通风优化方 案,方案内容包括最佳送风方式、布设水平位置、布设高度、布设间距。根据通风方案 计算结果对风机型号选取、以及隧道洞门设计提出了建议。  相似文献   

2.
修补喷漆在汽车服务领域中占有重要的地位,但有些维修人员只注重喷漆技术和维修质量的提高,对自身的安全防护往往容易忽视。针对油漆工的职业病油漆中毒不容忽视。本文分析了油漆工喷漆作业防护面具的种类及其特点,研究了油漆工呼吸系统防护面具的结构持点,介绍了油漆工喷漆作业特点及防护面具的选择方法,同时指出了喷漆作业应正确佩戴和使用防护面具。  相似文献   

3.
防毒面具指采用过滤方法,将空气中的某些有毒有害物质去除后用于呼吸的一类防护用品,其构成主要是面具部分和过滤元件部分,有些产品还用呼吸管连接面具和过滤元件。面具分全面具和半面具,过滤元件分防毒、防尘和尘毒复合防护(参见图1和图2)。任何防护都是有限的,防毒面具也不例外。它不适合任何缺氧环境,因为它不产生氧气,其防护性能往往取决于过滤的有效性和面罩的密合性。虽然人们对防毒面具的研究和应用已经有很长的时间,但仍然无法发明出适合所有有害物的过滤方法,因为过滤材料都有自身的适用范围。面罩的作用是将有害环境与过滤后的洁…  相似文献   

4.
本文通过分析防毒面具罩体内的流体在吸气情况下的数值变化情况,将面具流体模型导入ANSYS CFX模块中,对模型内部流场进行数值模拟和仿真,得出该面具模型在实验条件下的内部流场和压力分布情况。通过分析,不仅得到重要优化参数和改进参考,而且能够缩短研制周期,实现对模型的结构优化再设计。  相似文献   

5.
本文针对坑道施工中个体防护之急需,研制了一种具有呼吸追随功能的电动送风过滤式防护面具,在确保防护效果的基础上实现了自然舒适的呼吸,可有效预防和减少尘肺病等职业病的发生,并展望了该产品在其他领域的推广应用前景。  相似文献   

6.
正Scott安全公司的常规呼吸防毒面具(GSR)是专为军队设计,国防部(MOD)采用,在该面具成功设计的基础上,Scott安全公司研制了新一代防毒面具——应急响应人员防毒面具(FRR),提供给全球民用响应组织。FRR面具运用创新技术,减少了使用者负荷,改善了系统的整体性,并且操作简单,为化学、生物、放射性以及核威胁提供防护。该面具由传统的Din 40 thread圆形过滤器、电动式过滤防毒面具(PAPR)、自给正压式空气呼吸器  相似文献   

7.
大型相连容器中火焰传播的研究   总被引:1,自引:1,他引:0  
为了进一步了解相连装置中粉尘爆炸的火焰传播行为和压力发展,为该结构的安全防护设计提供有价值的信息,采用大型实验装置对相连容器中玉米淀粉/空气混合物爆炸时的火焰传播行为进行了实验研究,同时采用已开发的数值模型对实验进行仿真计算。实验表明:粉尘浓度的变化对粉尘爆炸的火焰传播行为有重要影响;在粉尘浓度很低的情况下,火焰仍然能够在管道中加速传播且爆炸发展的最终结果相当猛烈。数值模型采用欧拉-拉格朗日方法模拟两相流现象,通过求解非稳态的湍流两相反应流守恒方程对实验进行二维仿真,计算结果与实验结果符合性较好,表明该模型可以很好地应用于粉尘爆炸火焰传播的研究。  相似文献   

8.
为提升高处吊篮作业的安全防护水平,为建筑施工安全防护预警模型研究提供理论支持,针对安全防护不足和缺位对高处吊篮作业的不利影响,建立高处吊篮作业安全防护预警指标体系。通过对作业人员的筛选,作业信息采集及数据化处理,构建基于SVM(支持向量机)的高处吊篮作业安全防护预警模型。最后,通过对历史样本数据仿真模拟验证模型的适用性和可行性。研究结果表明:建筑施工高处吊篮作业安全防护预警模型的仿真模拟结果与实际结果相比较为吻合,从安全防护审批、个体防护用品、安全防护设施、安全防护标识、心理生理防护及作业条件防护6个方面进行分析构建的安全防护预警模型可为高处吊篮作业提供预警支持,并可作为建筑企业安全管理系统的一部分,推广至其他特种作业领域。  相似文献   

9.
为了消除或减少电磁波辐射对人体造成的危害,各种具有电磁防护功能的服装面料应运而生并得到迅速的发展,但是服装面料的电磁防护性能的测试费用一直较为昂贵.本文在研究织物电磁屏蔽原理的基础上,分析了服装面料的电磁防护性能与面料本身的电磁参数及厚度的关系.并且通过专业的电磁仿真软件Ansoft HFSS建立面料电磁屏蔽效能测试的仿真模型.将服装面料的电磁参数以及厚度值代入模型中,可以模拟测试获得服装面料的电磁屏蔽效能.这对于设计开发人员来说不仅可以减少昂贵的测试费用.加快开发的速度.还有利于设计出成本更低、防护性能更好的产品。  相似文献   

10.
通过对吸气式感烟火灾探测系统采样管网进行流体力学分析,建立了采样管网系统力学数学模型,采用了面向对象的编程技术,编制了工程管网设计模拟仿真软件,实现各采样点的探测灵敏度及探测响应时间的计算和对采样孔径的优化调整,在实际应用中取得良好效果。  相似文献   

11.
大型建筑内部火灾温度场的数值模拟   总被引:2,自引:0,他引:2  
利用CFD技术对在建筑火灾情况下,温度场的变化趋势进行数值模拟。针对大型建筑内部火灾温度场数值模拟特点,考虑建筑火灾中温度、烟气扩散以及尺度较大等因素,通过小尺度数值实验,在模型的效率性和准确性方面对不同模型加以比较、分析,选取带浮力修正的模型。同时,选用国际通用CFD计算软件FLUENT6.1针对某大型建筑内部火灾温度场进行数值模拟。并结合区域模拟软件CFAST对结果进行比较分析。表明CFD场模拟软件FLUENT6.1具有较高的可靠性,可针对大型工程项目进行分析模拟。  相似文献   

12.
用计算流体力学软件Fluent进行脱硫雾化喷嘴的内部流场的数值模拟,为喷嘴的优化设计找到一种准确、经济又快捷的方法,对加快脱硫设备国产化有一定的参考意义.  相似文献   

13.
High pressure tubular reactors for the production of Low Density Polyethylene (LDPE) are, for safety reasons, enclosed in a protective bay open towards the sky. They are becoming longer and larger due to production capacity increases. TECHNIP has historically designed these reactor bays based on Licensor information, which include more or less empirical correlations. Further capacity developments require the design of these concrete enclosures to be challenged. With this in mind, the present study shows the interest of implementing an innovative methodology based upon a risk-based approach to define new design criteria for the enclosure walls. The method, which combines both risk analysis with computational fluid dynamics modelling (3D CFD) and non-linear finite element analysis (NLFEA) tools, allows a clear determination of the design overpressure loads applied on walls and offers an optimisation of the concrete wall thickness. The CFD study also leads to a better understanding of the ventilation and efficiency of safety systems (gas detection, depressurisation) with possibility for improvement of the hazardous area classification rating.  相似文献   

14.
为确定铁路隧道救援站最佳通风结构,对烟道布置提出合理建议,采用计算流体力学(CFD)的方法,对铁路隧道救援站通风网络进行优化设计。同时,采用模拟计算的方法对救援站人员疏散进行模拟分析,确定救援横通道布置及防护门开度设置的合理性。研究结果表明:在同等通风参数工况设置下,采用多节点排烟竖井结构后各救援横通道流量分配更均匀,救援站压力平衡性更好,通风效率可提升15%;通过疏散模拟证实,在长560 m的紧急救援站范围内设置10条疏散横通道,横通道设1.7 m宽的逃生门能够满足疏散要求。  相似文献   

15.
This paper aims at contributing to the efficient design of explosion protection systems against confined explosions. The issue addressed concerns the quantitative estimation of the protective effect of explosion relief vents in the case of confined explosions inside tunnels. A series of virtual experiments performed by computer simulation, revealed how the number of vents, their diameter, as well as the angle between the vents and the tunnel, influences the blast wave attenuation. The computational study was performed considering a complicated large-scale tunnel configuration with branches on its half portion. The purpose was the calculation of the attenuation effect due to the presence of vents by comparing the total explosion-specific impulse developing at antidiametric positions inside the tunnel. Simulations were carried out via a three-dimensional numerical model built in the computational fluid dynamics code CFX 5.7.1, which has been validated in previous papers against experimental overpressure histories data demonstrating reasonable performance. Computer results showed that the use of branch vents provides an effective method for shock wave attenuation following an explosion, whereas their statistical elaboration revealed that the attenuation is mainly affected by the number of vents and their diameter. In contrast, the angle between the side vents and the main tunnel appeared to slightly affect the pressure wave weakening. Eventually, the quantitative influence of the above parameters was effectively illustrated in functional diagrams, so that the total attenuation effect may be promptly estimated, if the design variables are known. In addition, two statistical models with reasonable fitting to the calculated data are proposed, which express the attenuation effect as a dependent variable of the design variables including their interactions.  相似文献   

16.
Though dynamic operation of chemical processes has been extensively explored theoretically in contexts such as economic model predictive control or even considering the potential for cyberattacks on control systems creating non-standard operating policies, important practical questions remain regarding dynamic operation. In this work, we look at two of these with particular relevance to process safety: (1) evaluating dynamic operating policies with respect to process equipment fidelity and (2) evaluating procedures for determining the parameters of an advanced control law that can promote both dynamic operation as well as safety if appropriately designed. Regarding the first topic, we utilize computational fluid dynamics and finite element analysis simulations to analyze how cyberattacks on control systems could impact a metric for stress in equipment (maximum Von Mises stress) over time. Subsequently, we develop reduced-order models showing how both a process variable and maximum Von Mises stress vary over time in response to temperature variations at the boundary of the equipment, to use in evaluating how advanced control frameworks might impact and consider the stress. We close by investigating options for obtaining parameters of an economic model predictive control design that would need to meet a variety of theoretical requirements for safety guarantees to hold. This provides insights on practical safety aspects of control theory, and also indicates relationships between control and design from a safety perspective that highlight further relationships between design and control under dynamic operation to deepen perspectives from the computational fluid dynamics and finite element analysis discussions.  相似文献   

17.
调查重点行业企业在用呼吸防护用品质量状况,发现主要问题并研究对策,促进对呼吸防护用品的监督管理。对106家企业进行问卷调查,并随机抽样37家企业对在用69种呼吸防护用品进行检测。所有企业均配发了呼吸防护用品,样品合格率为40.58%,LA认证率33.33%。防尘口罩过滤效率和泄漏率的合格率较低(40.38%和48.08%),且国内外品牌差异具有统计学意义(P<0.05);防毒口罩防护时间合格率35.29%,防护时间、过滤元件通气阻力(30 L/Min和95 L/Min)的国内外品牌差异具有统计学意义(P<0.05)。  相似文献   

18.
As the increase of energy demand, the emission of CO2 is also likely to increase by at least the same amount because energy supply will be based on fossil fuels, which is more apparent in a number of developing countries. With the total global energy environment and rapid increase of domestic and foreign demand, renewable energy is the inevitable energy source for the future. In this context, the micro gas turbines (MGTs) by using bio-energy is being considered as a promising solution. In order to develop the real plant system of those technologies such as 60 kW-class micro gas turbine by using swine biogas, we finished the optimal design and construction for a biomass fueled MGT system. This paper consists of 1) MGT system design for swine bio gas 2) material evaluation for bio gas piping 3) computational fluid dynamics analysis for bio gas sulfur removal tower and sulfur absorption filter 4) the fundamental modeling using manufacturer's technical specifications and performance simulation by PEPSE-GT 5) field test and application of bio gas micro gas turbine. Finally, I established to set up the top-notched distributed power system design and optimal application.  相似文献   

19.
王伟  刘帅  白杰 《火灾科学》2016,25(4):179-182
使用反应路径分析法对Jet-A型航空煤油燃烧的气相燃烧机理进行简化。选用POSF-4658机理作为Jet-A燃烧的详细反应机理,该机理包含1607种燃烧组分、6633个基元反应机理。将飞机防火试验条件作为简化过程的初始条件,得到78种组分,196个反应机理的Jet-A燃烧机理。通过对Jet-A的简化反应机理、详细反应机理和JetA实验数据的比较可以发现,简化反应机理可以较准确地反映Jet-A型航空煤油在防火试验条件下的燃烧特性。利用常用的Jet-A型航空煤油简化机理计算的绝热火焰温度、点火延迟时间及层流火焰速度与本文提出的简化的计算值进行比较。结果表明,提出的简化机理在防火试验条件下具有较高的精确度。得到的Jet-A简化反应机理可为飞机防火试验的仿真研究提供燃烧场的化学反应动力学模型。  相似文献   

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