空气-水/吸湿溶液热湿传递特性分析(Ⅰ)可及处理区域

利用模型研究空气与水或吸湿溶液热湿传递过程的特性,得到两个相互独立的驱动力——焓差驱动力和相对湿度差驱动力.根据两驱动力的关系在焓湿图上确定了一个由空气进口等焓线、湿空气饱和线(或溶液等浓度线)、空气与水或溶液进口状态连线围成的三角形区域,不论流型、传热传质系数或流量如何变化,空气出口状态只能在该区域内变化,即为空气与...     

热湿条件下溶液除湿空调的性能分析

基于温-湿度独立控制理论,结合热湿地区的气候特点,设计了复合型太阳能溶液除湿空调系统(CSLDAS),通过建立热质传递控制方程,模拟分析了CSLDAS的除湿/再生性能和运行能耗。结果表明,CSLDAS能够综合利用多种可再生能源,有效降低空调能耗,并可有效增强除湿器/再生器的除湿/再生能力,减小对太阳辐射强度的依赖。本研究可为溶液除湿空调在热湿地区的节能设计提供理论指导。     

空气与水逆流直接接触热质交换过程模型计算及分析

Based on reasonable model hypotheses and the energy analysis of heat and mass transfer of air and water in a direct contact counter flow, a set of general equations that can describe the internal relationship between the state parameters of air and water and dimensionless parameters of transfer process are given. A method utilizing MATLAB to solve these general equations is also proposed. Calculations and analysis with the model of a cooling- dehumidifying process give a consistent result with that of previous experiment. A new method for designing equipment such as evaporating cooler and cooling tower, and for analyzing experiment data of heat and mass transfer of air and water in a direct contact counter flow can be derived from this study.     

空气与水逆流直接接触热质交换模型计算及与实验比较

According to general equations deducted from a model of heat and mass transfer of air and water in direct contact counter flow reported in the author‘s previous work, the outlet parameters of air and water counter flow through a paper wet pad were calculated by using the MATLAB-software. Comparing the calculation results with experiment data of prior researchers, the deviation of calculated outlet air wet bulb temperature from experimental outlet air wet bulb temperature was less than 10%, the deviation of calculated outlet water temperature from experimental outlet water temperature was less thang 9%, and the deviation of calculated outlet air dry bulb temperature from experimental outlet air dry bulb temperature was less than 10% when NTUh was more than 0. 6. The deviation of calculated outlet air dry bulb temperature from experimental outlet air dry bulb temperature was more than 10% when NTUh was less than 0. 6. The model calculations were in good agreement with experiments and the general equations could be used to design evaporation cooling equipment, such as wet pad and so on.     

空气与水直接接触热质交换顺流和逆流过程特性比较

根据空气与水顺流和逆流直接接触热质交换过程的模型公式,利用MATLAB软件对一冷却减湿过程进行计算,分析了空气与水顺、逆流直接接触热质交换过程的传质单元数NTUm、传热单元数NTUh、水气比β以及空气与水的出口状态参数、过程的热交换系数和接触系数的不同,得出了有用的结论,为蒸发冷却设备的设计及实验数据分析,提供了理论指导和新方法。     

常压水热Ca-Na-Cl溶液中用磷石膏制备α-半水石膏

引言常压水热电解质溶液中,二水石膏(calcium sulfate dihydrate,DH)、α-半水石膏(α-calcium sulfate hemihydrate,α-HH)、无水石膏(calcium sulfate anhydrate,AH)三相之间的转化对于无机     

垂直管中管径突变对空气-水两相流流型的影响（Ⅰ）突缩接头

Flow patterns upstream and downstream of a sudden-contraction cross-section in a vertical straight pipe were presented. By comparing with flow patterns in uniform cross-section vertical tubes, the effect of the sudden change in pipe diameter on flow patterns was analyzed. Flow pattern transition mechanisms were discussed and transition criteria for flow pattern transitions were deduced accordingly using the dimensional analysis.     

干-湿冷却系统对空冷机组热经济性影响的分析

受环境温度影响, 空冷机组夏季工况的运行背压高, 严重限制了机组的带负荷能力, 并影响机组的热经济性和安全性。分析了一种干-湿混合冷却系统, 将汽轮机排汽分流出一部分通过循环水冷却, 以降低机组夏季工况背压。建立了干-湿混合冷却系统对机组热经济性影响的数学模型, 并以某330 MW直接空冷机组为例揭示了机组背压和净功率随主蒸汽流量、湿冷分流量以及环境温度的变化规律。结果表明:主蒸汽流量为1120 t·h^-1、湿冷分流量为175 t·h^-1时, 机组出力从326.266 MW达到330 MW满负荷运行, 提高了3.734 MW, 背压由46.8 kPa下降到31.9 kPa, 机组的热耗率降低了110.9 kJ·(kW·h)^-1, 发电标准煤耗率降低了4 g·(kW·h)^-1。     

基于热不平衡考虑的溶液除湿/再生传热传质系数(Ⅱ)实验与模型计算分析

溶液除湿和再生装置是溶液除湿空调系统中的重要组成部件,常用的溶液除湿和再生装置内部空气和溶液流道一般是非常复杂,其内部传热传质规律也不易精确得到.建立一套最简单的降膜除湿/再生装置,进行逆流除湿和再生实验.采用本文(I)报中的基于热不平衡考虑的Le-hD测量法计算得到溶液平板降膜的耦合传热和传质系数随各种实验工况的变化...     

热裂解-气相色谱质谱法（Py-GC/MS）分析涂料中的溶剂和树脂

采用热裂解–气相色谱质谱（Py-GC/MS）方法对未知涂料样品进行分析,树脂在高温惰性环境下裂解为低分子物质,再通过气相色谱质谱分析。不需要繁复冗长的分离步骤,利用最后裂解碎片产物反推被测化合物的组成和结构,对低分子量的溶剂、高分子量的树脂进行准确定性,对于常规方法难以定性的混合树脂,热裂解气相–质谱联用仪可以快速定性树脂成分,对于涂料配方的改进、涂料性能的提升有重要意义。     

水分散性Kevlar纳米纤维用量对天然橡胶/水分散性Kevlar纳米纤维复合材料力学性能和水刺激-力学响应的影响（英文）

研究了水分散性Kevlar纳米纤维的用量对天然橡胶/水分散性Kevlar纳米纤维复合材料力学性能及水刺激-力学响应的影响。结果表明,水分散性Kevlar纳米纤维可有效改善复合材料的力学性能,在其用量为20份(质量,下同)时,复合膜的储能模量达到30.30MPa,吸水后降低了57.26%,吸水前后的变化明显,说明添加20份水分散性Kevlar纳米纤维的复合材料具有最佳的力学性能及水刺激-力学响应。     

橡胶基质对橡胶/细菌纤维素晶须复合材料的水刺激-力响应性能的影响（英文）

分别选用丁苯橡胶(SBR)、天然橡胶和羧基丁腈橡胶作为基质,采用蒸发法将细菌纤维素晶须(BCWs)分别与3种橡胶胶乳混合,制备了橡胶/细菌纤维素晶须复合材料,研究了橡胶基质对复合材料吸水性能及水刺激-力响应性能的影响。结果表明,加入BCWs后,3种橡胶基质制备复合材料的吸水性能都得到增强,常温储能模量均明显下降,幅度可达到2个数量级。3种基质中以非极性橡胶SBR制备的SBR/BCWs的吸水性能和水刺激-力响应性能为最佳。