Experimental measurements of the hydrodynamic performance and structural loading of the Transverse Horizontal Axis Water Turbine: Part 1

This paper is the first of three, which outline the procedures and results for a set of experiments carried out on various configurations of the Transverse Horizontal Axis Water Turbine (THAWT), which is a horizontally orientated variant of the Darrieus cross-flow turbine. Tests were conducted in the combined wind, wave and current tank at Newcastle University on a 0.5 m diameter rotor, while the flow depth and velocity were varied over a range of realistic Froude numbers for tidal streams. Various configurations of the device were tested to assess the merits of varied blade pitch, rotor solidity, blockage ratio and truss oriented blades. Experiments were carried out using a speed controlled motor/generator, allowing quasi-steady results to be taken over a range of tip speed ratios. Measurements of power, thrust, blade loading and free surface deformation provide extensive data for future validation of numerical codes and demonstrate the ability of the device to exceed the Lanchester-Betz limit for kinetic efficiency by using high blockage. This paper covers the experimental procedures and results for the hydrodynamic performance for the parallel bladed variant of the THAWT device. The second paper covers the hydrodynamic loading of the parallel bladed rotor and the third covers both hydrodynamic performance and loading of the truss configured THAWT device.     

混凝土灌注桩桩头渗水的处理及预防措施

混凝土灌注桩桩头渗水对桩体混凝土受力和基底防水产生影响,对混凝土结构中的钢筋造成腐蚀。结合工程实例,对桩头渗水产生的原因进行分析,主要有操作经验不足、责任心不强,灌注器具不合格,混凝土质量指标不符合要求,灌注接近结束时拔管速度过快、灌注终了超灌高度测量不准,基土含水量高、水压大等;出现桩头渗水可采用人工剔除或注浆封堵处理;介绍了预防措施,包括加强作业人员培训,强化灌注器具检查,严控混凝土质量,重点监管终灌时的状态,做好基坑内降水工作等。     

某电厂烟气脱硫机组GGH改造的分析与探讨

主要对某电厂石灰石—石膏法烟气脱硫机组GGH的改造进行了介绍,并通过对造成GGH堵塞的原因进行分析与探讨,提出了一系列解决方案和措施,并探讨采用湿烟囱防腐取代GGH的可能。     

小分子封闭提高固定化青霉素酰化酶的稳定性

为提高青霉素酰化酶的催化性能和热稳定性,在酶组装过程中添加小分子试剂对介孔泡沫硅载体表面过量的活化位点进行封闭。详细考察了小分子添加质量分数和种类对青霉素酰化酶负载率、催化活力及热稳定性的影响。实验结果得到:经精氨酸封闭的固定化酶活力提高至1.92倍;甘氨酸封闭的固定化酶5 h的50℃热稳定性提高至2.9倍,甘氨酸和谷氨酸封闭的固定化酶50℃热处理25 h仍保持87.9%和82.2%的残余活力;甘氨酸和谷氨酸封闭的固定化酶最适催化pH值向中性偏移且对pH值的耐受性增强。结果表明,在青霉素酰化酶共价组装过程中添加合适的小分子封闭能显著提高酶的催化性能和热稳定性。     

城市道路堵塞问题浅析与初步对策

从我国多数城市的痼疾交通堵塞问题入手,结合北京和上海城市道路发展实例加以分析,试图找出造成城市交通堵塞问题的根本原因,经过分析得出几个初步解决问题的构想,并对于城市道路发展展开大胆预想,从多角度、多层次为我国城市道路堵塞问题开出药方。     

影响石灰石-石膏湿法烟气脱硫系统水平衡的设计因素

对石灰石-石膏湿法烟气脱硫系统及其吸收塔在不同设计条件下进行水平衡计算,分析了设计过程中水平衡的分析思路和影响因素,为相关设计提供参考。     

烟气脱硫系统阻力增大原因分析及处理措施

介绍了江苏华电扬州发电有限公司在运行中相继出现了烟气脱硫系统阻力增大而影响系统性能稳定运行的问题。分析了烟气脱硫系统阻力增大对运行影响的原因,采取了相应措施后,烟气阻力减小,能耗降低。     

Application of a three-component competitive adsorption model to evaluate and optimize granular activated carbon systems

A recently developed kinetic model for granular activated carbon (GAC) adsorbers (COMPSORB-GAC) that quantitatively describes the adsorption of trace organic contaminant in the presence of competing natural organic matter (NOM) was applied to evaluate the performance of different GAC system configurations: conventional fixed-bed adsorbers, layered upflow carbon adsorbers (LUCA), and moving-bed adsorbers (with few or many bed sections). COMPSORB-GAC separately tracks the adsorption of three components: a trace compound, a strongly competing NOM fraction that reduces trace compound equilibrium capacity, and a pore-blocking NOM fraction that reduces kinetics. Performance was simulated for various design criteria and with model parameters derived for two natural waters with significantly different NOM concentrations. For the range of simulated conditions and with baseline performance defined by a fixed-bed adsorber, LUCA generally reduced carbon usage rates (CURs) by 15-35%. A 2-section and a 16-section moving-bed reactor reduced baseline CURs by 20-30% and 45-55%, respectively. Projected CURs for the water source with a relatively high NOM concentration were 2-3 times higher for all reactor configurations and indicated that NOM preloading would cause performance deterioration in deep GAC beds, which highlights the importance of source water quality. These results show how COMPSORB-GAC can be used in a comprehensive, site-specific optimization of GAC systems to ensure robust system performance and to balance capital and operating costs.     

高性能光阻式颗粒计数仪的设计与实现

为了提高光阻式颗粒计数仪的测量准确性和长期稳定性,着重设计了传感器的前置放大器以及光源闭环调节系统,使传感器的输出电压稳定,体积小巧便于拆装,取样系统增加了流速稳定装置以及光电定体积检测,减少测量误差,整机的电磁兼容设计提高了仪器的信噪比。长期的实验结果表明,仪器的测量准确度优于5%,重复性小于3%,各项性能指标均符合行业标准。     

燃煤火电厂脱硫系统烟气换热器密封技术改进及应用

针对燃煤火电厂600MW等级发电机组锅炉烟气脱硫系统GGH设备存在的漏风问题,结合设备的设计、施工、运行、维护等环节,对解决GGH漏风的密封技术进行改进性研究,提出了弹性双层可调密封,已在电厂实际应用。