水口参数对异形坯连铸结晶器内流场的影响

依据湍动能理论 ,本文建立了结晶器内钢液的三维湍流模型 ,开发了计算程序 ,研究了不同水口状态下异形坯结晶器中钢水的流动特性。利用本模型所得计算结果与实测结果吻合较好 ,并可对现场生产进行离线分析。

板坯连铸机浸入式水口相关技术参数研究

通过对板坯连铸机中间包浸入式水口尺寸、形状、插入深度、流场、换渣线及水口安全使用寿命等技术参数研究,确定了合理的浸入式水口相关参数,提高了水口的使用寿命,确定了水口的安全使用时间,稳定了结晶器钢液流场,保证了保护渣良好熔化和坯壳润滑,使板坯连铸机生产稳定顺行,铸坯质量得到提高。

Comprehensive evaluation of water quality parameters in Tianjin Dagu Dainage Canal

In this paper, some indices of sulfide, organic carbon, oil and heavy metals （copper, lead, zinc, cadmium, mercury, arsenic and chromium） in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons in 2012 - 2013 are selected, and Water Quality Pollution Index （API） is applied to evaluate water quality indices, aiming for the systematic evaluation of the water quality of Dagu Dainage Canal. The results showed that four stations of D3, D6, D7and D9 for S2 had the type Ⅱand Ⅲ of water; others had the type Ⅰ ; the total level of TOC, TPH, Cu, Pb, Zn, Cd, Hg, As and Cr were type Ⅰ, Ⅳ, Ⅱ, Ⅴ, Ⅱ, Ⅴ, Ⅲ, Vand Ⅴ. Water Quality Pollution Index （API） was 3.28, which illustrated Dagu Dainage Canal was in the state of contamination and the degree of pollution exceeded the standard functional areas.

Effect of inlet configuration on hydrocyclone performance

Inlet configuration is important parameter of hydrocyclones,which has great impact on the classification performance.The effects of inlet configuration on the precise classification were studied by computational fluid dynamics under variouscombinations of inlet diameter and inlet velocity.The results showed that a high sharpness of classification was achieved withspecific inlet diameter and inlet velocity.The separation efficiency of the coarse particles by underflow significantly decreased wheninlet had an oversize diameter owing to a stronger short-circuit flow.It is resulted from the chaotic flow and the stronger pressuregradient around the vortex finder.Meanwhile,a low separation efficiency of the fine particles by overflow was achieved when inletvelocity was high,which indicated a low sharpness caused by the overlarge centrifugal force.

Application of Multivariate Model Based on Three Simulated Sensors for Water Quality Variables Estimation in Shitoukoumen Reservoir,Jilin Province,China

This study applied a multivariate model based on three simulated sensors to estimating water quality variables in Shitoukoumen Reservoir,Changchun City,Jilin Province,China,including concentration of total suspended matter,concentration of chlorophyll-a and non-pigment matter absorption.Two field campaigns for spectra measurements with a total of 40 samples were carried out on June 13 and September 23,2008.The in-situ spectra were recalculated to the spectral bands and sensitivities of the instruments applied in this paper,i.e.Landsat TM,Alos and P6,by using the average method.And the recalculated spectra were used for estimating water quality variables by the single model and multivariate model.The results show that the multivariate model is superior to the single model as the multivariate model takes the combined effects of water components into consideration and can estimate water quality variables simultaneously.According to R2 and RMSE,Alos is superior to other sensors for water quality variables estimation although the precision of non-pigment matter absorption inversion performed the second.

Physico-Chemical Analysis of Korapuzha River and Estuaries

Korapuzha is a short river of 40 km with a drainage area of 624 km^2, flowing from dense forest and empties into the Arabian sea. It is formed by the confluence of two streams Agalapuzha and Punnoorpuzha. In this study the samples were collected from Agalapuzha, Punnoorpuzha and Korappuzha, Korapuzha estuaries. The temperature and pH were monitored on the site and the remaining parameters were analyzed in the laboratory. The physical quality parameters such as color, odor, appearance and chemical quality parameters such as pH, alkalinity, chloride, nitrate, nitrite, sulphate, ammonia, dissolved oxygen, total solids, total hardness, and iron have been evaluated. Compare the physical and chemical parameters. The physico-chemical analysis shows that the samples have high level of salinity, sulphate, total solids and total hardness. The results show that the water is affected by the intrusion of sea water into the river by excess excavation of sands from river for the construction of buildings and other anthropogenic activities which leads to environmental destruction.

浸入式水口及其对板坯连铸结晶器流动行为的影响

板坯连铸是各种板带材生产的初级成形工序,铸坯质量与结晶器冶金效果密切相关,其中浸入式水口的作用至关重要。针对连铸生产技术现状与发展要求,在回顾板坯连铸浸入式水口发展历程的基础上,总结并讨论了至今对浸入式水口结构、工艺参数及其材质与结晶器冶金行为关系的认识。综合表明,浸入式水口直接影响着钢水注入结晶器后的流动、传热与凝固行为,进而影响结晶器冶金性能与连铸过程铸坯质量的控制效果,但至今尚缺乏定量的水口设计参数准则。鉴于实际生产中各类钢种可浇性、铸坯断面与拉速的差异性,从铸机生产组织和电磁控流角度出发,探讨了单一水口在多断面、多工况下实现理想浇铸的可能性。