性能强化后对曲轴轴颈负荷及磨损的影响

内燃机曲轴轴颈的磨损量是衡量内燃机寿命的一个重要指标。针对近年来内燃机性能越来越强化的实际状况，在内燃机缸内压力和转速增加的情况下，分析计算了内燃机曲轴的曲柄销和主轴颈的轴承负荷的情况，绘制了各种工作状态下内燃机曲柄销和主轴颈的磨损图。研究表明：气缸压力和转速升高后，曲柄销和主轴颈的磨损均呈现增加趋势。为此，提出了改进曲轴轴承负荷分布情况，减小磨损的方法。     

核电主泵电机水润滑硅化石墨径向轴承试验研究

采用水润滑推力轴承试验台考察了核电主泵电机硅化石墨径向轴承在蒸馏水润滑下的性能，结果表明，在运行过程中，径向轴承能够建立连续水膜，基本不产生磨损；在启动／停止的过程中，瓦面产生磨损。1500h的运行表明，硅化石墨径向轴承的耐磨性较高，使用寿命能够达到设计要求。     

内燃机轴承磨损失效过程的试验研究

本文提出了内燃机轴承磨损过程的假说,拟定了接近内燃机实际工况的试验方案。以S195柴油机连杆轴瓦的磨损为例,通过在我校设计的动载滑动轴承磨损试验机上的试验,从轴瓦径向厚度的变化以及油样光谱、铁谱的分析,初步探讨了内燃机轴承的磨损过程及其影响因素的相互关系。     

电站风机轴承损坏原因分析

分析了电站送风机轴承磨损，腐蚀直至损坏的原因，即由于安装质量以及密封失效等造成的振动加剧以及润滑失效等因素综合作用而导致轴承损坏。文中提出了预防及维护的措施以及所取得的良好效果。     

进气灰尘对柴油机磨损的实验研究

通过向柴油机进气系统加入不同粒度的灰尘，研究了进气灰尘粒度对柴油机各零部件的磨损及对柴油机功率的影响。实验结果表明，在实验条件下进气灰尘对柴油机气缸套和活塞环的磨损最大，而轴承的磨损很小。２０－５０μｍ的灰尘与柴油机的磨损影响最大，空气滤清器应尽可能滤去这尺寸范围的灰尘。     

柴油机主轴承磨损状态监测的试验研究

本文设计了在不同转速、不同负荷、不同主轴承间隙下的柴油机台架试验，通过对测得的柴油机机身、主轴承上的应变和振动信号进行时域和频域分析，寻找柴油机主轴承间隙与特征函数之间的规律，从而实现对柴油机主轴承磨损状况的监测。     

内燃机主要磨损对性能指标影响的估算

曲柄连杆机构轴承副的磨损是内燃机的主要磨损，导致其平均指标压力和指标效效率的下降。推导了它们的计算公式，并对公式进行了深入的分析和讨论，得出了压缩比与平均指示压力的下降程度呈正相关关系的结论。此外，还给出了计算实例，这些计算公式简单实用。     

柴油机主轴承磨损理论计算与分析

以X4105G柴油机为研究对象进行了主轴承负荷、轴心轨迹、纵横向挤压、旋转油膜力及主轴颈纵向加速度的理论计算及分析,得到了主轴承负荷、间隙、润滑油温度对主轴承磨损的影响,其中第4档主轴承负荷最大,第3档主轴承纵向加速度最大,纵向油膜力与轴承负荷密切相关。理论计算与分析的结果可为监测主轴承的磨损状态提供理论依据。     

柴油机磨损故障振动诊断机理的研究

本稳分析了现有振动方法在柴油机故障诊断研究和实际应用方面存在的问题，提出了基于振动产生和传播机理的诊断研究方法，介绍了基于这种方法的活塞－缸套磨损和滑动主轴承磨损故障振动诊断机理的理论分析和试验研究结果，提出了一种新的振动诊断法。     

船用低速柴油机轴承磨损监测系统工作原理的研究

随着船用低速柴油机轴承磨损监测系统的启用,真正实现了轴承磨损状态的实时监测和开验轴承次数的减少。介绍了船用低速柴油机轴承磨损监测系统的一般工作原理、功能与特点,对其关键技术,下止点位置传感器的信号处理,尤其是速度补偿技术进行了重点分析,为更好地用好该系统提供参考。     

滤槽除尘器在静电除尘器改造中的应用

介绍了滤槽除尘器的结构，材料及除尘原理，滤槽除尘器在不同工况下的除法效率，附加脱硫率，阻力和排放浓度等参数的测试结果，利用滤槽除尘器时的改造方案，运行中应注意的问题及实验机的运行情况。     

中小型燃煤锅炉尾部飞灰回收装置

中小型燃煤锅炉,特别是链条炉,尾部受热面易产生积灰,由于煤质及锅炉运行工况的不同,会对受热面产生污染,堵塞作用,有时又可以产生磨损问题,现提供一种简单、高效率应用在燃煤锅炉尾部受热面的飞灰回收装置。     

Why environmental dust influences solar energy harvesting

In order to minimize dust effects on optical surfaces related to the solar energy harvesting, adhesion between the active surface of energy harvesting device and the dust particles needs to be lowered. Consequently, the pinning force for the dust particles reduces, and the dust particles can be removed via creating the self‐cleaning effect. The wetting state of the active surface becomes critical towards reducing the pinning force. In this case, hydrophobic surfaces remain favorable reducing the dust adhesion on the surfaces. In the present perspective, characteristics of the environmental dust particles and their effects in humid air ambient are presented. The methods for dust removal from the surfaces and the optical transmittance reduction by the dust particles are discussed. The challenges and future perspectives of surface texturing towards achieving hydrophobicity and optical transmittance are also introduced.     

Study on the influence of Mg content on the risk of hydrogen production from waste alloy dust in wet dust collector

We use a proprietary automatic Al–Mg alloy–water reaction test apparatus to compare the hydrogen evolution profiles of Al-xMg (x = 10%,20%) with different particle sizes, characterize the waste Al-xMg alloy dust particles before and after reaction through SEM, EDS, and XRD, and present a three-stage four-step hydrogen evolution model of Al-xMg (x ≤ 35%) alloy dust particles. It is discovered that the reaction of the Al–Mg alloy in water is a hydrogen evolution–adsorption–slow diffusion process. The particular β-Al₃Mg₂ in Al-xMg (x ≤ 35%) will adsorb the resulting hydrogen to form MgH⁺ and adhere to the surface of the particles. As the Mg content in the alloy increases, the hydrogen evolution reduces. The entire process lasts around 5–6 h, with maximum hydrogen conversion rate of 54% (Al–10%Mg, d (50) = 12 μm, α = 0.544). Our hydrogen evolution model provides very useful theoretical references for avoiding hydrogen explosion in Al–Mg alloy manufacturing facilities.     

煤矿自旋转喷雾降尘装置的实验与模拟

煤矿生产过程中会产生大量的煤尘,目前煤矿降尘技术主要以喷雾为主。设计了一套自旋转喷雾降尘系统,该系统结构简单,水源不需要增压,具有良好的喷雾效果。同时,由于喷嘴数目较少,雾化范围比较广,节约水源。通过流体力学软件FLUENT对压力-旋流式喷嘴的喷雾特性进行k-ε湍流模型数值模拟,采用离散相模型(DPM)追踪雾滴的运动轨迹,清晰地反映出雾场的情况和实验成对比。     

Hydrogen inhibition by using Cr(NO3)3·9H2O in the wet dust removal system for the treatment of aluminum dust

Aluminum dust could react with water and produce hydrogen gas during its treatment process in a wet dust removal system, leading to a risk of hydrogen fire and explosion. In this work, in order to explore an effective method for inhibiting the production of hydrogen, inhibition experiments were carried out in an aluminum dust and water reaction tester using Cr(NO₃)₃·9H₂O solution as the Hydrogen Inhibition Method (HIM). Scanning Electron Microscopy (SEM) was used to characterize the surface of aluminum particles before and after the experiments while the reaction products were analyzed by X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and Energy Dispersive Spectroscopy (EDS). By using Cr(NO₃)₃·9H₂O solution, the inhibition film was observed on the surface of aluminum particles after the experiments and the main components of the film were analyzed to be Al(OH)₃ and Cr(OH)₃, which could prevent contact between aluminum particles and water and thus prevent the reaction between them. Based on the shrinking core model, the physicochemical mechanism of the HIM method was identified. The proposed HIM using Cr(NO₃)₃·9H₂O solution was validated to be very effective and could mitigate potential hydrogen fire and explosion accidents with a low cost.     

Hydrogen inhibition in wet dust removal systems by using calcium lignosulfonate (CLS)

Wet dust removal systems pose hydrogen fire and explosion risks because accumulated aluminium dust can react with water to produce hydrogen gas. Traditionally, hydrogen sensors, alarm devices, explosion-proof electrical components and pressure relief devices are installed in wet dust removal systems to mitigate such risks. However, these safety strategies cannot fundamentally prevent the occurrence of hydrogen fires and explosions. In this work, calcium lignosulfonate (CLS), which is an abundant, inexpensive and renewable chemical, is used to inhibit hydrogen production. Through a series of hydrogen inhibition experiments using CLS solution, a hydrogen inhibition method is proposed. The hydrogen evolution curves of aluminium particles after reaction with CLS solutions at different concentrations reveal that when the concentration of the CLS solution reaches 0.5 g/L, essentially no hydrogen gas is produced. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) are used to characterize the aluminium particles before and after reaction. The film formation behaviour of CLS on the surface of aluminium particles is characterized. The results show that CLS is a good inhibitor and that the adsorption of CLS on the aluminium particle surface obeys the Langmuir adsorption isotherm. Additionally, Fourier transform infrared (FT-IR) analysis is conducted to reveal the physicochemical mechanism of hydrogen inhibition. The application of CLS solution in wet aluminium dust removal systems results in the maximum reduction in hydrogen explosion risk.     

浅析煤矿粉尘危害及防治技术

叙述了井下粉尘对矿工健康和安全生产的危害问题,指出,推广煤矿清洁生产,从源头控制污染、消除污染,是确保煤矿安全生产的科学之举,提出,从排尘、减尘、降尘、除尘和个人防护5个方面开展综合治理的防范措施.     

Inhibition of hydrogen production reactions in the wet dust removal system using CeCl3 solutions

For treatment of aluminum dust, a wet dust removal system has been used worldwide. During treatment, aluminum dust is inhaled into a water tank of the dust collector. As hydrogen production reactions are likely to take place in the water tank, there exists a great risk of fire or explosion accidents associated with the wet dust removal system. Based on field research and laboratory experiments, Hydrogen Inhibition Method (HIM) by using CeCl₃ solutions was proved capable of inhibiting reactions between aluminum dust and water. When the concentration of CeCl₃ solutions reached 6.02 g/L, there was basically no hydrogen gas produced. SEM, EDS and XPS characterizations were used to assess the aluminum particles before and after being reacted with water or CeCl₃ solutions, respectively. Shrinking core model was utilized to identify the corresponding chemical reaction kinetics. Additionally, a physicochemical mechanism was established to explain these phenomena.     

浅谈DZD水管式锅炉除尘系统的改造

简要介绍了一例企业生产用锅炉的除尘系统的改造。叙述了改造前原系统存在的问题，具体的改造措施及改造后取得的经济与社会效益。