高温高压下湿空气循环中增湿塔的计算研究

Humidification is an important step in humid air turbine system. The calculation on humidification is carried out at 423.15—573.15K, 5—15MPa. The results suggest that to produce high-enthalpy moist air, high water temperature and large water flow are needed. The water temperature is the most sensitive parameter to the humidification tower. And it is better for the humidification tower to work at temperature higher than 523 K when the system pressure is higher than 5 MPa. The comparison between the model used in this paper and ideal model shows that the ideal model can be used in simulation to simply the calculation when the temperature is lower than 473 K and pressure is lower than 5 MPa.     

直接空冷系统散热器喷雾增湿量研究

在大型直接空冷火电厂的运行中普遍存在夏季因为散热器换热不良引起出力受阻的问题。针对这一问题,各大火电厂一般采用喷雾增湿法降低空冷散热器入口空气温度,改善空冷散热器的换热效果,降低机组背压,从而提高机组出力。通过分析喷雾增湿法的原理,在提出喷雾增湿法的数学模型的基础上,用商用M atlab软件进行了仿真计算。通过仿真计算得出环境温度与喷水量的关系,从而为喷雾增湿法的应用提供了一定的理论依据和运行参考。     

Two dimensional dynamic modeling of a shell-and-tube water-to-gas membrane humidifier for proton exchange membrane fuel cell

Water management is a crucial factor in determining the performance of proton exchange membrane fuel cell (PEMFC) for automotive application. The shell-and-tube water-to-gas membrane humidifier is useful for humidifying the PEMFC due to its good performance. Shell-and-tube water-to-gas membrane humidifiers have liquid water on one side of the tube wall and a dry gas on the other. In order to investigate humidifier performance, a two-dimensional dynamic model of a shell-and-tube water-to-gas membrane humidifier is developed. The model is discretized into three control volumes – shell, tube and membrane – in the cross-sectional direction to resolve the temperature and species concentration of the humidifier. For validation, the dew point temperature of the simulation result is compared with that of experimental data and shows good agreement with only a slight difference. The distribution of humidification characteristics can be captured using the discretization along the air-flow direction. The humidification performance of two different flow configurations, counter and parallel, are compared under various operating conditions and geometric parameters. Finally, the dynamic response of the humidifier at the step-change of various air flow rates is investigated. These results suggest that the model can be used to optimize the inlet flow humidity of a PEMFC.     

Size and mineral composition of airborne particles generated by an ultrasonic humidifier

This study describes the size distribution and concentration of particles expelled by a portable, 3‐L ultrasonic humidifier. The ultrasonic humidifier was filled with waters of varying mineral content and hardness. Aerosol size distributions were measured during 8 hours of humidifier operation in a typical bedroom. Humidifiers produced approximately 1.22 × 10¹⁰‐2.50 × 10¹⁰ airborne particles per milliliter of water consumed, resulting in airborne particle concentrations of 3.01‐5.91 × 10⁴ #/cm³, with modes ranging between 109 and 322 nm in diameter. The emission rate of particles varied by water type from 1.02 × 10⁹ to 2.27 × 10⁹ #/s. Lower mineral waters produced fewer, smaller particles when compared to higher mineral waters. Chemical analyses of particles collected with a cascade impactor indicated that the minerals in emitted particles had the same relative mineral concentrations as the fill water. Our results demonstrate that ultrasonic humidifiers should be considered a source of inhalation exposure to minerals dissolved in water, and that the magnitude of exposure to inhalable particles will vary with water quality.     

节能的直接空气增湿器

描述了产业用纺织品生产中节能的解决方案--直接空气增湿.与传统气动装置相比,通过采用一种基于空气辅助雾化原理的新方法,Karasto公司生产的Geka Couplings成功地大幅度降低了汽化所需的能量.     

Modeling and experimental validation of H2 gas bubble humidifier for a 50 kW stationary PEMFC system

Ensuring uniform membrane hydration in a PEMFC (Proton Exchange Membrane Fuel Cell) is important for its performance and durability. In this study, a bubble humidifier for humidifying hydrogen in a 50 kW PEMFC pilot plant was designed, built, and modeled. Initial tests, carried out by humidifying air, show that a dew point temperature of higher than 59 °C is attained when operating the PEMFC plant at nominal power at 65 °C. The model simulation results show good agreement with experimental data and the model is used for studying humidifier performance at other conditions. Steady state simulation results suggest that by increasing the heating water flow rate, the humidifier outlet dew point temperature can be increased by several degrees because of improved heat transfer. Finally, dynamic simulation results suggest that the humidity of the hydrogen can be controlled by manipulating the heat supply to the humidifier.     

Design of an air humidifier for a 5 kW proton exchange membrane fuel cell stack operated at elevated temperatures

Air humidification is a crucial issue for superior performance of proton exchange membrane fuel cell (PEM fuel cell) stacks. In this work, an air humidifier is proposed for a 5 kW PEM fuel cell stack working at elevated temperatures, e.g., 90–95 °C. The high temperature coolant exiting the stack is utilized to pre-heat the air in the heat exchanging tubes of the humidifier, and the heated air is humidified with deionized water supplied by a nozzle fixed in a top cavity. Both the tubes and the nozzle are properly designed to ensure sufficient heat transfer and superior atomization. Humidification performance is evaluated under different operation conditions. The nozzle is able to inject well-atomized water with uniform droplet diameter. With the variation of inlet air flow rate, the relative humidity (RH) of the outlet air increases at the beginning, then decreases gradually due to the attenuation of dew point (DP) temperature. However, the humidification performance can be improved when higher temperature deionized water is injected or high temperature coolant is supplied. At a coolant temperature of 95 °C, the outlet air DP temperature is maintained over 80 °C with 25 °C injection water. Moreover, better humidification performance is achieved when the injection water flow rate is controlled according to the working conditions of the stack.     

烟草真空回潮机真空装置的腐蚀原因探讨及技术改进

分析造成烟草真空回潮机的抽真空装置腐蚀的原因，并进行技术改进，改造后腐蚀周期从1年延长到8年以上。     

硫酸排渣系统改造

针对云硫化工厂硫酸装置排渣系统污染和铁矿粉流失严重的问题,介绍其技术改造过程.     

新型膜增湿器实验方法研究及结果分析

为了更好地发挥膜增湿器的工作性能,有效地对空气进行增湿,对燃料电池系统用膜增湿器的工作原理进行了分析,并对其性能做了大量的实验研究.以增湿后气体的相对湿度作为性能指标,确定了影响膜增湿器性能的主要因素,分别分析了各个因素对性能的影响程度,为今后膜增湿器的设计和使用提供了有效依据.