Numerical modelling of storm surges in the Arabian Sea

Using the basic hydrodynamic equations governing motion in the sea, a coastal zone numerical model has been developed for the prediction of storm surges along the west coast of India. Numerical experiments were performed with the help of this model to simulate the surge generated by the devastating 1975 Porbandar cyclone. The results of the experiments were in good agreement with the reported values along the Gujarat coast.     

环缝气垫高效耐磨旋风除尘器的研究

为了经济、有效地提高旋风除尘器的耐磨性能和除尘效率，提出了在旋风除尘器内壁设置环缝套圈的增效防磨新方法，在理论上探讨了高速含尘气流对器壁的磨损机理和二次扬尘现象。在２ｔ燃煤锅炉上不同烟气流速下的对比实验表明，该新型旋风除尘器的除尘效率比普通旋风器提高５％，平均阻力系数比普通旋风除尘器降低１０％。     

旋涡流化床燃烧特性的试验研究

在鼓泡流化床悬浮空间一定高度加入适量的二次风而形成的旋涡流化床燃烧具有高效、低污染、投资少等优点,本文介绍了在一热态试验台上所进行的不同煤种、不同流化速度、床温、二次风率、喷口直径、入射角度等条件下燃烧特性规律的研究。试验结果表明:二次风加入后,流化床内的燃烧特性得到明显改善;细颗粒飞灰含碳量减小6～9个百分点;燃烧效率提高3～6个百分点.     

Behaviour of inorganic constituents of municipal sewage sludge during fluidized-bed combustion

The fate of main heavy metals in municipal sewage sludge (As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, and Zn) was investigated using a fluidized-bed reactor. The behaviour of metals in the incinerator was explored by comparing metal contents in the two main ash streams: bottom (in-bed) ash and ash separated by a cyclone (cyclone-catch ash). All metals showed enrichment in the cyclone ash. The ash originating from sewage sludge is thermally quite stable consisting of quartz, hematite, spar(s), mica(s), apatite, and anhydrite. It does not soften nor becomes sticky and does not tend to agglomerate at temperatures up to 950°C.     

Comparison of different sampling heads applied for investigation of welding fume

Welding fume samples were collected in two Hungarian welding plants, where different types of steels were welded with metal active gas (MAG) welding. Welding fumes were sampled with “fixed point” and personal sampling techniques applying different sampling heads: Institute of Occupational Medicine (IOM) sampler and conical inhalable sampler (CIS) for the inhalable aerosol fraction and the Higgins-Dewell (HD) cyclone for the respirable fraction. When sampled, the welding fume samples were digested with the mixture of nitric acid and hydrogen peroxide in a closed vessel microwave digestion system. The Cr, Mn, Ni and Co contents of the solutions were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). Iron was analysed only by the ICP-AES method. Metal concentrations of the workplace air were calculated for the three samplers, and the results were compared to each other. The differences of the metal concentrations determined by the different inhalable sampling heads, which were paired during the sampling, proved not to be significant. Therefore, the IOM and CIS heads can be equally used for the sampling of welding fume. Finally, the distributions of metals were determined between the inhalable and respirable fractions. Metal concentrations in the respirable aerosol fraction were 57-98% of the concentrations in the inhalable fraction. These high rates of metals in the respirable aerosol call the attention to the increased health risk of the welding fume.     

Application of Tikhonov regularization method to wind retrieval from scatterometer data Ⅱ: cyclone wind retrieval with consideration of rain

According to the conclusion of the simulation experiments in paper I, the Tikhonov regularization method is applied to cyclone wind retrieval with a rain-effect-considering geophysical model function (called GMF+Rain). The GMF+Rain model which is based on the NASA scatterometer-2 (NSCAT2) GMF is presented to compensate for the effects of rain on cyclone wind retrieval. With the multiple solution scheme (MSS), the noise of wind retrieval is effectively suppressed, but the influence of the background increases. It will cause a large wind direction error in ambiguity removal when the background error is large. However, this can be mitigated by the new ambiguity removal method of Tikhonov regularization as proved in the simulation experiments. A case study on an extratropical cyclone of hurricane observed with SeaWinds at 25-km resolution shows that the retrieved wind speed for areas with rain is in better agreement with that derived from the best track analysis for the GMF+Rain model, but the wind direction obtained with the two-dimensional variational (2DVAR) ambiguity removal is incorrect. The new method of Tikhonov regularization effectively improves the performance of wind direction ambiguity removal through choosing appropriate regularization parameters and the retrieved wind speed is almost the same as that obtained from the 2DVAR.     

四入口液-液旋流分离器分离性能数值模拟

多入口旋流分离器能在入口速度较低的情况下实现传统旋流器在入口速度较高时才能达到的分离效果,同时具有更加稳定和对称的流场分布。为了进一步验证多入口液-液旋流分离器的分离性能以及溢流分流比和入口流速对其分离性能的影响,本文基于欧拉-欧拉多相流模型,采用群体平衡方程（PBM）对四入口液-液旋流分离器分离性能进行了数值模拟。研究结果表明：在入口流速恒定时,旋流器综合分离效率随着分流比的升高呈先上升后下降变化趋势,溢流分流比为0.22时,旋流器综合分离效率达到最高,此时分离效率为95.66%。当溢流分流比为0.22时,随着入口流速的增大,四入口液-液旋流器分离效率呈先上升后下降最后趋于平缓变化趋势,当流速为10m/s时,到达油滴剪切破碎临界条件,此时分离效率最高为96.78%。研究结果可为四入口液-液旋流分离器现场应用和适用性提供理论指导。     

关于隆安选煤厂产品方向及选煤工艺的思考

介绍了隆安选煤厂所选煤的煤质特征和其产品方向定位,着重论述了选煤方法,结论为：产品方向宜作为动力电煤,原煤采用脱泥有压两产品重介旋流器分选,采用TBS煤泥分选机分选;细煤泥经浓缩机浓缩后,由快开式隔膜压滤机脱水回收。     

扩展式旋风静电除尘器空气粉尘驱进速度的计算

阐述扩展式旋风静电除尘器的降尘机理，描述空气粉尘的荷电过程，研究荷电粉尘的受力和运动规律，建立气流粉尘的动力学方程．计算粉尘的驱进速度，并讨论介质阻力系数对驱进速度的影响．最后给出在工业除尘的应用实例．     

非线性水平动量平流作用对热带气旋运动的影响

本文将热带气旋视为与环境间有动量交换的系统，着重分析了非线性水平动量平流作用对热带气旋运动的影响，从理论上解释了一些热带气旋路径异常变化的原因。