福建省太阳总辐射和地面辐射平衡的分布

首先利用福州市的辐射观测资料，建立计算太阳总辐射的经验公式，并计算福建省各市、县的太阳总辐射的年、月平均辐照度。然后利用地区代表站的地面反射率，求得福建省各月、年地面所吸收的太阳辐射能的分布。再利用地面温度、气温、水汽压和总云量，计算得出福建省各地的地面有效辐射的月、年平均辐照度。最后得出福建省各月、年地面辐射平衡的分布。     

福建太阳总辐射和地面辐射平衡的分布

首先利用福州市的辐射观测资料，建立计算太阳总辐射的经验公式，并计算福建省各市、县的太阳总辐射的年、月平均辐照度。然后利用地区代表站的地面反射率，求得福建省各月、年地面所吸收的太阳辐射能的分布。再利用地面温度、气温、水汽压和总云量、计算得出福建省各地的地面有效辐射的月、年平均辐照度。最后得出福建省各月、年地面辐射平衡的分布。     

利用卫星云图对1979年夏季青藏高原月旬总辐射场的研究

本文讨论了利用TIROS-N卫星白天(地方时12—15时)在青藏高原上空拍摄的可见光云图照片估算地面总辐射的可能性,揭示了从卫星照片上获得的高亮度云云量与地面总辐射值间的关系。在此基础上计算了2°×2°经纬网格点上的月、旬总辐射,绘制了青藏高原地区1979年5—8月逐月和逐旬的总辐射分布图。利用卫星云量计算地面总辐射,为我们确切了解高原中西部广大无人区的总辐射形势场提供了客观依据。     

从辐射强度变化分析深圳太阳辐射气象条件

计算太阳辐射典型年,对与到达地面太阳辐射强度变化密切相关的气象和环境因素进行分析研究,总结出深圳太阳辐射气象条件,运用典型天气进行验证。结果发现:1)温度、相对湿度、降水量、云量、最大风速的风向、沿海站的极大风速和大气气溶胶均与到达地面太阳辐射强度有不同程度的关联,云量与直接辐射呈显著的负相关;2)一天中深圳太阳总辐射最大值出现在11:00～12:00,太阳有效辐射时间为05:00～18:00;月总辐射和直接辐射最大值均出现在每年中的6～7月份;3)辐射强度与空气质量指数(AQI)相关性明显,大气污染物对直接辐射起到较明显的削弱作用,其中O3与辐射关联度较大,其次PM2.5、PM10等在傍晚时对辐射具有一定的削弱作用;4)前汛期云量和水汽、降雨等对辐射的影响作用大。     

北京地区太阳紫外辐射的长期变化趋势及分析

对实际天气条件下北京地区1990年1月至1992年8月太阳辐射预测资料进行了详细分析。得到实际天气条件下到达地面的太阳紫外辐射的计算公式。结果表明,计算值与预测值吻合得比较好,利用该式计算了北京地区1979年1月-1996年6月的太阳紫外辐射,讨论了1979-1996年北京地区太阳紫外辐射的变化趋势及不同因子（臭氧、水汽、气溶胶等）对太阳紫外辐射的影响。     

武汉地区太阳总辐射与气象要素的关系研究

利用武汉市2007年1月1日至2008年12月31日逐时太阳总辐照量和气象要素(气温、相对湿度、云量等)资料,分析武汉地区逐时太阳总辐照量与逐时气象要素的关系,找出对总辐照量有显著贡献的因子,对比各个气象要素对太阳总辐照量的贡献,利用2007年总辐照量和常规气象要素分季节建立逐时多元线性回归方程,并利用回归方程分季节逐时预报2008年总辐照量,最后进行误差分析。结果表明:太阳总辐照量夏季最多,冬季最少;太阳总辐照量与气温、相对湿度、水汽压及云量(低、总)有关,其中相对湿度及云量(低、总)与总辐照量负相关。分季节分时次建立回归方程发现:春季总辐照量与相对湿度、气温和总云量关系较密切;夏季总体上与春季类似,但气温对总辐照量的贡献不大;秋季总辐照量与气温、总云量、相对湿度、水汽压有关;除了和秋季相同的影响因子外,低云量对冬季总辐照量也有一定的贡献。     

太湖地区光合有效辐射(PAR)的基本特征及其气候学计算

光合有效辐射（Photosynthetically Availble Radiation,简称PAR）是植物进行光合作用的重要能量来源。利用太湖湖泊生态系统研究站1998年1－12月一年的气象辐射观测资料，分析了该地区有效辐射以及占太阳总辐射比例的变化特征，并分析了光合有效辐射的极值及对应的光合有效辐射占总辐射的比例和它与云量的的关系，最后提出了适合本地区的光合有效辐射的气候学计算方法。     

基于TSI地基云图的云量反演方法研究

基于金昌地区全天空成像仪(TSI-880)观测资料,进行地基云图还原,并根据样本统计分析得到合理的红蓝比阈值(0.84)来区分云和晴空,构建批量云图还原与云量计算自动化系统。结合该地区光伏电站辐射观测站的太阳辐射资料,将系统计算的云量(修正云量)和TSI自行分析结果(原始云量)分别与太阳辐射资料进行对比。结果表明原始云量与太阳辐射衰减相关系数为0.3,修正云量与太阳辐射衰减相关系数为0.88,具有更好的相关性。这对于太阳辐射临近预报有重要意义。     

影响地面太阳辐射及其谱分布的因子分析

针对目前全球变暗(明)的热点问题,利用一个高光谱分辨率的辐射传输模式,计算了全球42种大气下到达地面的太阳辐射通量及其在近红外、可见和紫外各光谱区间的比例,详细分析了大气内部因子(水汽和臭氧、云和气溶胶等)以及外部因子(太阳天顶角和地表反照率)对它们的影响.结果表明:中低云对地面太阳辐射通量及其谱分布有很大影响,高云的影响很小.水汽和臭氧的敏感性试验表明,水汽对地面近红外辐射的影响较大,而臭氧对可见和紫外辐射的影响较大.气溶胶对地面太阳辐射的影响仅次于大气的吸收作用,是不容忽视的.此外,太阳天顶角和地表反照率都会对地面太阳辐射通量及其谱分布产生重要影响.     

水汽增强温室效应的探讨

从研究水汽的热力学特性出发,通过定性分析和定量计算,着重探讨水汽对全球气候变暖的影响。通过研究,推测水蒸气凝结是通过辐射放热的,其凝结过程中向地面的辐射可能是大气温室效应的一个主要原因。     

Modeling the development of hydrogen vapor cloud considering the presence of air humidity

A three-dimensional CFD model for large-scale liquid hydrogen spills is developed and validated by the experiments carried out by NASA. The effect of humidity on the development of hydrogen vapor cloud is emphasized, with the modified expressions of Lee model accounting for the phase changes of water and hydrogen. The results show that the numerical prediction is more consistent with the experiment considering the presence of air humidity. The condensation of water in the atmosphere increases the buoyancy of the vapor cloud, and promotes the diffusion of the cloud in vertical direction. The dimension of the cloud in streamwise direction changes little under different humidity, due to the balance between the height-dependent wind speed and the induced buoyancy. The scope of visible cloud indicated by the condensed water vapor expands with the increasing air humidity, and still lies within the flammable domain when the relative humidity approaching to 75%. Water vapor condensation induces the cloud temperature rise under the same concentration, and the leeward part is more influenced compared with the upwind part.     

An experimental study on vapor transport of a hollow fiber membrane module for humidification in proton exchange membrane fuel cells

Water management is key in the optimization of proton exchange membrane fuel cell performance and durability. Humidifiers can be used to provide water vapor to cathode air, ensuring the proper operation of proton exchange membrane fuel cells. In this study, water vapor transport characteristics of hollow fiber membrane modules were investigated in shell-tube humidifiers under isothermal conditions, using two different test jig constructions: a convection jig and a diffusion jig. The mass transfer rate of water vapor was evaluated via the impact of various operating parameters, including temperature, flow rate, pressure, and relative humidity of inlet wet air, flow arrangements, and surface area of the tube side. The result was presented by the water vapor transport rate from wet air flow to dry air flow across the hollow fiber membrane. It was found that humidification performance could be improved with higher operating temperature, flow rate, and relative humidity of inlet wet air, lower pressure, larger membrane surface area, higher convection effect, and substituting co-current with counter-current flow configuration.     

Longwave sky radiation parametrizations

New empirical models for predicting daily mean thermal radiation from both clear and cloudy skies are proposed. Their great advantage is that they only use the three following variables, which can be measured easily by an automatic weather station at the ground level: the air temperature, the water vapor pressure, and the clearness index. In particular, neither cloud cover measurement nor temperature or humidity profiles are needed. The models are adjusted to measurements carried out in Gembloux, a town 40 km away from Brussels, Belgium. The most elementary model, based solely on the water vapor pressure, gives already reasonable estimations with a correlation coefficient 0.914. The best model is based on all three variables with a correlation coefficient of 0.958.     

土壤温度和水分日变化实验

在露天和温室两种条件下 ,对 2 0 0mm× 5 0mm (高×半径 )的土壤床中温度和水分的日变化规律进行了实验研究。结果表明 :1)土壤温度随着太阳辐射和大气温度的周期性变化而呈现出周期性变化 ,随着深度的增加 ,温度变化的滞后效应越明显 ;2 )夏天的白天大部分时间中 ,土壤浅层的温度高于深层的温度 ;从下午的某个时间至第二天日出 ,这种现象则相反 ;3 )云层夺太阳幅射的阻挡 ,对土壤表层的温度有较大的影响 ,而对较深处影响不大 ;4)由于有遮阳设施 ,温度中土壤的最高温度要比露天情况下低 ;5 )从傍晚开始 ,土壤中的水蒸汽出现冷凝 ,浅层土壤中水蒸汽开始冷凝的时间比深层早 ,露天下土壤中水蒸汽的冷凝现象比温室中更明显     

Spray cooling in a closed system with different fractions of non-condensibles in the environment

Spraying liquid on a hot surface is an effective method for dissipating high heat fluxes from integrated circuit chips. In this study, HAGO nozzle was used to create the spray and a closed system with water as a test liquid was used. The effect of presence of non-condensibles in the closed system on the heat transfer coefficient in both single phase and boiling modes were investigated. Maintaining an air partial pressure of 3.1 kPa, while varying the vapor partial pressure from 7.3 kPa to 97.9 kPa, the total system pressure was varied from 10.4 kPa to 101 kPa. Experiments were also conducted by keeping the system pressure constant at 101 kPa and varying the air partial pressure inside the chamber from 2.75 kPa to 93.7 kPa. In each case, liquid temperature corresponded to the saturation temperature corresponding to partial pressure of vapor and this was also approximately the ambient temperature of vapor and air mixture in the chamber. It was found that in the single phase regime, overall heat transfer coefficient for lower concentration of non-condensibles in the system is much higher than that for the case with more non-condensibles. In boiling, heat transfer coefficient depends on the total system pressure in the system. For the same system pressure, data for different partial pressures of air overlap. For a water mass flux of 17.5 ml/min/cm² at room temperature, critical heat flux as high as 230 W/cm² was obtained at a surface temperature of 127 °C.     

“Partial pressures” of humid air in wide pressure and temperature ranges

“Partial pressure” in humid air is a question very much concerned by scientists and no satisfactory answer has been found to date. This paper proposes a novel method to obtain the “partial pressures” of the water vapor and dry air in humid air. The results obtained by the proposed method are quite different from that obtained by Dalton’s partial pressure law. The fundamental behaviors of water vapor and dry air are studied in depth in wide pressure and temperature ranges. Semi-permeable membrane models are proposed and applied for both saturated and unsaturated humid air. “Improvement factors” are developed to quantitatively describe the magnitude of the interaction between dissimilar molecules. One discovery is that the “partial pressure” of the water vapor in saturated humid air equals P_s, rather than (f·P_s) which was formerly believed. The other is that the interaction between dissimilar molecules may be omitted when temperature is above “cutting-off temperature” for unsaturated humid air. This paper satisfactorily answers the quest of “partial pressures” in humid air from a new perspective.     

适用于宽温度和压力范围的湿空气热力性质分段计算方法

根据计算范围的不同,提出适合宽温度、压力范围,涵盖多个湿空气热物理性质参数的分段计算方法：在低温、低压范围内将湿空气看作理想混合气体,采用理想气体状态方程建立模型计算湿空气的热物理性质参数;在高温、高压范围内将湿空气看作干空气和水蒸气的实际二元混合气体,采用维里方程建立湿空气的半经验模型计算湿空气的热物理性质参数.分析确定了分段计算的分界点,并说明了分段计算的连续性.结果表明：与参考文献的计算结果相比,采用该文提出的湿空气热力性质分段方法得出的计算结果的最大误差仅为4.5%,且计算过程简单快捷,易于程序实现,可用于绘制焓湿图.     

氢氧加湿燃烧的数值模拟

介绍了利用CHEMKIN 4.1软件中封闭的全混同性反应器模型模拟加湿情况下氢氧燃烧的方法,同时基于详细的氢氧燃烧化学反应动力学机理分析了初始反应温度、反应压力及水蒸气添加量等对氢氧燃烧的影响。模拟结果表明,初始反应温度、反应压力及水蒸气添加量等因素均会对氢氧燃烧的点火延迟时间和燃烧最高温度产生一定程度的影响,其中水蒸气添加量的变化对氢氧燃烧的最高温度及火焰传播速度的影响较为显著。这对后续在实验室中进行氢氧加湿燃烧研究可提供有益的指导。     

滑动弧等离子体协助甲烷蒸汽重整制氢

采用甲烷为主要原料,在常温和常压条件下,利用滑动弧等离子体放电技术,进行了甲烷与空气、水蒸气重整反应的试验。试验研究了过量空气系数、反应气流量和水蒸气含量等参数对甲烷与空气、水蒸气重整反应的影响,并对重整副产物进行了分析。试验表明,当过量空气系数为0.8时,氢气选择性最高可达到45.9%;反应气流量达到14L/min时,单位氢气生产成本最低;在反应气中加入一定量的水蒸气,有利于重整反应的进行。     

Numerical study of hydrogen triple flame response to mixture stratification,ambient temperature,pressure, and water vapor concentration

Mixing layer simulations of spark-ignited H₂/air that detail the influence of mixing layer thickness, domain pressure and air temperature, and water vapor concentration have been carried out. The stabilization speed of the propagating flame front is shown to increase with increasing mixing layer thickness as a result of streamline divergence ahead of the triple flame structure. The pressure changes considered are small (1, 2 bar), and within this range the pressure has only a modest effect on propagation speeds, while air layer temperature effects (298 K, 750 K) are pronounced. Higher adiabatic flame temperatures produced by elevated air temperature have been shown to lead to increased formation of nitrogen oxides. This tendency can be counteracted by increasing inert concentration. Therefore, the influence of water vapor concentration on emissions has been considered in studies where air layer species concentrations are replaced with up to 50% water by mole. Resulting changes in flame structure, heat release rates, flame speed, and emission concentrations – estimated through use of the standard Zeldovich NO mechanism, are given. Data trends for all parameter effects have been related to expected qualitative predictions for direct-injection hydrogen internal combustion engine behavior.