共查询到20条相似文献,搜索用时 58 毫秒
1.
根据所设计的液排渣粉煤燃烧器,用相似模化理论建立冷态试验装置,测定了试验燃烧器的三维流场,对两种不同旋流数(一次风)的流场进行了对比,以此对所设计的燃烧器作了分析和评价。 相似文献
2.
3.
4.
5.
6.
本文简要总结了液排渣粉煤旋风燃烧器的研制过程及主要成果.文中介绍了冷态试验和热态试验的装置系统及试验方法,通过冷态试验研究了燃烧室内的流场结构,明确了主要操作参数和结构对流场的影响。热态试验研究了装置的燃烧性能,并积累了操作经验.文中就燃烧器的结构、燃烧器的技术性能、煤种及煤质、操作等方面介绍了主要的研究结果。采用该项技术可收到显著的节能效果,并可显著地减少大气污染,改善劳动环境。这对于燃煤工业炉窑的技术进步和“以煤代油”炉窑的技术改造具有重要意义. 相似文献
7.
8.
对液排渣煤粉燃烧器结构参数和一次风参数予以不同煤种着火过程的影响进行了系统的数值模拟,揭示了其规律,为设计液排渣煤粉燃烧器提供了依据。 相似文献
9.
本文对立式粉煤液排渣旋风炉进行了模拟研究.讨论了一次风口、二次风口、出口结构及一、二次风量比对流场的影响.用颗粒模拟了粉煤在炉内的空间行为;用油模拟了液态渣在炉壁的行为。 相似文献
10.
冯旭 《金属材料与冶金工程》1987,(4)
我国煤炭资源丰富,分布地区较广,按目前产量可开采200年以上。从现有的能源生产结构可知,我国煤炭所占比例比世界平均值约高一倍。因此,合理利用煤炭资源和研究新的燃烧技术与煤炭转化技术,对于实现2000年的总目标,具有非常重要的意义。 1985年我们决定自行研制适合我国国情的粉煤液排渣燃烧器。当年着手设计,并分别在北京钢铁学院和常熟市喷咀厂建立了冷态试验台和热态试验炉。现在已经完成了冷态试验,并在热态试验炉上排出了液渣,取得了初步成效。一、粉煤液排渣燃烧器的结构 相似文献
11.
12.
The importance of two major issues in obtaining an almost complete cold flow model (ACCFM) from a tensile test, that is, the necking conditions (including the Considère condition and tensile strength) and several selected representative flow points in both pre- and postnecking strain hardening regions, is emphasized. It is shown using the AISI 1010 steel for automatic multistage cold forging (AISI 1010 equivalent) that all the traditional fundamental flow models (FFMs) such as the Ludwik, Voce, Hollomon, and Swift models cannot simultaneously satisfy the two major issues. A general blended flow model (BFM) is proposed, which is a linear combination of known basis blending functions satisfying the necking conditions. The number of basis blending functions is unconstrained. The constants of the linear combination, called blending coefficients, are calculated by a set of linear equations to meet the selected representative flow points. Numerous combinations of basis flow functions are tried. It has been shown that there is no interpolation case among all the obtained BFMs but that there are a few ACCFM-acceptable cases among them, which are based on the extrapolation of the basis blending functions. 相似文献
13.
14.
Particle image velocimetry technique was used to analyze the trailing vortices and elucidate their relationship with turbulence properties in a stirred tank of 0.48 m diameter, agitated by four different disc turbines, including Rushton turbine, concaved blade disk turbine, half elliptical blade disk turbine, and parabofic blade diskturbine. Phase-averaged and phase-resolved flow fields near the impeller blades were measured and the structure of trailing vortices was studied in detail. The location, size and strength of vortices were determined by the simplified λ2-criterion and the results showed that the blade shape had great effect on the trailing vortex characteristics. The larger curvature resulted in longer residence time of the vortex at the impeller tip, bigger distance between the upper and lower vortices and longer vortex life, also leads to smaller and stronger vortices. In addition, the turbulent kinetic energy and turbulent energy dissipation in the discharge flow were determined and discussed. High turbulent kinetic energy and turbulent energy dissipation regions were located between the upper and lower vortices and moved along with them. Although restricted to single phase flow, the presented results are essential for reliable design and scale-up of stirred tank with disc turbines. 相似文献
15.
本文数值模拟了圆筒燃烧室内双股同心强旋流流场及其湍流参数的分布。计算中,对Kolmogorov-Prandtl旋涡粘性系数假定中的经验系数Cμ做了初步调试,认为Cμ对不同流场及同一流场中的不同点都有可能不同,而且Cμ应具有各向异性的特性。实验结果表明:数学模型与计算方法,对模拟轴对称强旋流场是可行的。 相似文献
16.
17.
本文介绍圆筒燃烧室内双股同心旋转射流物理模型实验与数值模拟的研究结果。数值模拟按著者最近提出的湍流涡量输运方程,采用ψ-ω方法及K-ε湍流双方程模型,Rodi提出的壁函数,以及Spalding教授等提出的计算湍流回流的方法。本文工作表明,用涡量-流函数法及K-ε双方程模型计算强旋流及回流是可行的。 相似文献
18.
19.
介绍了天铁炼钢厂中间包水模实验原理和过程,分析了斜、直、圆三种型式挡渣墙模拟结果,提出了合理的挡渣控流方案,在生产实践中使用效果良好。 相似文献