吸附除湿固定床结构的实验研究与性能分析

本文设计了一种固体吸附床,通过实验分析了床体内部温度和湿度的变化规律及其产生原因,并就存在的问题对吸附床的传热传质性能进行了分析,在此基础上提出了改进方案.     

两种不同形式太阳能吸附床制冷性能比较

应用集总参数法建立太阳能集热吸附床能量守恒的数学模型,对以活性炭-甲醇为工质对的真空集热管吸附床和平板式集热吸附床进行模拟分析比较,分析吸附床的逐时吸附速率,得到集热床的温度和时间的函数关系,求解函数并绘制出吸附床温度随时间变化的曲线图。对太阳能吸附式制冷系统进行性能分析,对比分析两种吸附床系统的优缺点,并提出了改进的方向。     

固定吸附床固体吸附除湿的床结构实验研究

本文介绍了2种吸附床结构:叉排和顺排,通过实验分析了不同进口空气参数条件下2种吸附床结构的空气处理量、吸附过程床体进出口空气温差、总除湿量以及床体压降的变化规律及产生的原因,并就存在的问题对2种吸附床结构的传热传质过程进行了分析,提出了解决方案.     

交替边界条件下多孔床传热传质特性数值模拟

针对回热式新风系统中多孔介质回热器在交替边界条件下的传热传质特性进行了研究。采用数值方法针对表面温、湿度交替变化的对流边界条件,对多孔床与空气的非稳态传热传质过程进行了模拟计算,获得了多孔床内温度场和含湿量场。在此基础上,分析了该类多孔床的传热传质特性,并比较了关键因素对多孔床内温度和含湿量变化的影响。计算结果表明,多孔床与空气之间的热质交换主要发生在交界面附近较浅的薄层,往底层的传递十分缓慢。多孔床与空气的热、质交换效果受气流流速影响较为明显。     

改性炭对磺胺甲噁唑的吸附及解吸特性

采用商品活性炭和金属氧化物改性炭作为吸附剂,研究了几种活性炭对磺胺甲噁唑(SMZ)的吸附及解吸特性。结果表明:SMZ在几种活性炭上的吸附动力学符合拟二级动力学方程;SMZ的吸附均可采用Freundlich、Langmuir和Langmuir-Freundlich模型进行拟合,Langmuir-Freundlich吸附模型能更好地描述活性炭和改性炭对SMZ的吸附行为;铁、锰氧化物的存在对活性炭的比表面或者孔结构影响不大,并且其对活性炭吸附水中SMZ的性能影响甚微;与AC-Fe和AC-Mn相比,AC-0上吸附的SMZ更易解吸,改性炭负载的金属氧化物与SMZ的表面络合作用增强了AC-Fe和AC-Mn对SMZ的化学吸附,并且改性炭的MnOx和FeOx能氧化降解部分SMZ。     

针刺板吸附床强化传热的理论研究

针对吸附床作为固体吸附式制冷系统核心部件的重要性,提出了一种新型针刺板吸附床,利用针刺丰富的扩展表面为传热面,降低吸附剂与床体之间的热阻,从而提高了吸附床的传热能力。     

制冷除湿系统模拟方法研究进展

概述了制冷除湿的特点和传热传质模型的种类,介绍了压缩机、节流装置、换热器等部件模型,系统模型和系统算法,指出了制冷除湿模拟存在的问题和未来的研究方向.     

固定吸附床结构对传热效果的影响

本文设计了一种圆管外填充吸附剂、圆管内走湿空气的吸附床结构,分析了有筛网和无筛网结构的吸附床床层温度以及吸附量和脱附量随时间的动态变化。通过对2种结构吸附床传热效果的分析比较,指出有筛网的吸附床结构传热效果较好。     

改性活性炭对水中对氯酚的吸附性能研究

在惰性气氛下,采用不同温度热处理脱附活性炭表面的含氧酸性官能团,从而改变活性炭表面的化学性质。以对氯酚为吸附质,考察了改性前后活性炭的平衡吸附量,研究了温度、溶液pH值对吸附剂吸附性能的影响。分别用准一级动力学方程和准二级动力学方程研究了活性炭的吸附行为。结果表明,惰性气氛下热处理活性炭能提高其对对氯酚的吸附量。     

椭圆螺旋微管束反应器参数优化与性能评价

为提高储氢反应器的传热及吸放氢速率,对现有金属氢化物反应器进行了系统的综合分析与评价.基于强化传热传质特性,设计优化出了一种高效的新型椭圆螺旋微管束反应器(ESMBR),其具有结构紧凑、传热效果好、反应速度快及操作方便等特点.对研究的储氢反应器进行了建模,并通过实验验证了该模型的准确性和有效性.通过COMSOL软件对比ESMBR、圆形螺旋微管束反应器(SMBR)和直管微管束反应器(MTBR)的数值模拟结果得出,ESMBR在储氢时具有优异的传热传质性能.进一步的敏感性分析结果表明,ESMBR中椭圆螺旋管结构参数的敏感性顺序为主直径(Dc)>椭圆截面长轴(A)>椭圆截面短轴(B)>节距(Pt)>螺旋角度(α).采用多元价值取向模型对不同的反应器方案进行了系统的分析评估,结果表明:ESMBR的综合优度高达0. 845,对比结果也明显优于其他反应器,在氢能领域将有广阔的应用前景.     

太阳能固体吸附式转轮制冷机性能分析

针对活性炭纤维-乙醇太阳能固体吸附式转轮制冷系统,采用沿吸附床周向的一维均匀压力场数学模型,对转轮吸附床温度场进行了静态模拟计算;从吸附床的内、外部特性参数出发,全面而系统地分析了这些参数的改变对系统性能、平衡脱附率以及吸附量的影响。结果表明,在转轮吸附床的内部参数中,转轮吸附床的转速、吸附剂的填充密度对系统的性能有着较大的影响;在其外部参数中,冷却气体入口流速、蒸发温度等因素对系统影响比较大。     

对固体吸附式制冷系统中新型多孔吸附床的初步研究

固体吸附式制冷系统中核心部件是吸附床,由于床体内的吸附剂是多孔介质,床体与吸附剂之间接触热阻大,所以热传导能力差。如果使用一种高导热系数的材料为多孔吸附床的床体,将硅胶吸附剂均匀附着在多孔吸附床的孔体内,利用多孔结构丰富的内表面积为传热面,那么传热速率会比传统方法提高较多。     

Experimental investigation on adsorption capacity of ACF–methanol pairs for cooling application

Solar cooling technology is very popular among other conventional cooling technologies due to increment in global warming effects. In solar cooling technology, solar-powered adsorption refrigeration system has potential to compete with other non-conventional cooling technologies, that is, Absorption, PV-based, Waste-heat-driven and Biogas cooling. The main objective of this research work was to investigate the adsorption capacity of methanol onto activated carbon fibre in the temperature range of 15–80°C during an isobaric adsorption process. To correlate adsorption characteristics’ data of the experiment, the Dubinin–Astakhov equation is used. From a series of experiments, the maximum adsorption capacity was found to be 0.44?kg/kg of ACF by maintaining packing density of bed at 110?kg/m³. The effect of heat generator temperature on adsorption capacity is also studied in this investigation.     

太阳能固体吸附式制冷技术在我国建筑中的应用

介绍了太阳能固体吸附式制冷的原理及研究概况,分析了太阳能在制冷系统中的应用,提出了在我国用太阳能固体吸附式制冷作为建筑空调冷源的可行性及三种方案。     

太阳能驱动的固体吸附式转轮制冷机在西北地区运用研究

详细阐述了以固体吸附式制冷为基础的转轮式制冷机的工作原理、制冷设备以及工质对的选用,并进行了可行性计算分析,说明了以活性炭纤维-乙醇为工质对的转轮式制冷机是利用太阳能等低品位热源比较理想的制冷装置.在我国西北地区,太阳能利用有很大潜力,西部开发过程中,将太阳能利用于制冷,对西北和我国的经济发展是十分有利的.     

A review on performance improvement of an absorption refrigeration system by modification of basic cycle

The vapour absorption refrigeration system is not so much used commercially because of its low performance. The performance of an absorption refrigeration system is required to make it an efficient alternative of vapour compression refrigeration systems. This paper reviews different research on modification of absorption systems contributing to enhance the performance of absorption refrigeration systems. This study suggests that the performance of absorption refrigeration is improved by using double-effect and semi-generator absorber solution heat exchanger arrangement. The coefficient of performance of absorption refrigeration is also improved by the combination of different refrigeration cycles (hybrid refrigeration cycle) such as compression–absorption and ejector–absorption.

Abbreviations: COP: coefficient of performance; GAX: generator absorber solution heat exchanger; ARS: absorption refrigeration system; ECOP: ecological coefficient of performance; CAHP: compression-assisted absorption heat pump     

Branched pore kinetic model analysis of geosmin adsorption on super-powdered activated carbon

Super-powdered activated carbon (S-PAC) is activated carbon of much finer particle size than powdered activated carbon (PAC). Geosmin is a naturally occurring taste and odor compound that impairs aesthetic quality in drinking water. Experiments on geosmin adsorption on S-PAC and PAC were conducted, and the results using adsorption kinetic models were analyzed. PAC pulverization, which produced the S-PAC, did not change geosmin adsorption capacity, and geosmin adsorption capacities did not differ between S-PAC and PAC. Geosmin adsorption kinetics, however, were much higher on S-PAC than on PAC. A solution to the branched pore kinetic model (BPKM) was developed, and experimental adsorption kinetic data were analyzed by BPKM and by a homogeneous surface diffusion model (HSDM). The HSDM describing the adsorption behavior of geosmin required different surface diffusivity values for S-PAC and PAC, which indicated a decrease in surface diffusivity apparently associated with activated carbon particle size. The BPKM, consisting of macropore diffusion followed by mass transfer from macropore to micropore, successfully described the batch adsorption kinetics on S-PAC and PAC with the same set of model parameter values, including surface diffusivity. The BPKM simulation clearly showed geosmin removal was improved as activated carbon particle size decreased. The simulation also implied that the rate-determining step in overall mass transfer shifted from intraparticle radial diffusion in macropores to local mass transfer from macropore to micropore. Sensitivity analysis showed that adsorptive removal of geosmin improved with decrease in activated carbon particle size down to 1 μm, but further particle size reduction produced little improvement.     

太阳辐射换热空调制冷技术研究

本文从太阳辐射换热空调制冷的基本概念入手,简单介绍了太阳辐射空调制冷的基本原理、现有太阳辐射换热空调技术存在的问题及解决的途径,并对太阳辐射换热空调系统的效率进行了全面的分析,为太阳辐射换热空调制冷技术的优化提供可靠的依据。     

吸收器传热传质强化的研究综述

本文综述了国内外溴化锂吸收式制冷机吸收过程强化传热传质的有关研究现状。强化方法主要包括改进传热管、添加表面活性剂、改进吸收式制冷系统等,如改进传热管以增大传热吸收面积和吸收液的扰动;加入表面活性剂,以强化Marangoni(马拉格尼对流)效应;改进吸收式制冷系统以增大制冷剂的质量流量,并增大吸收器内的吸收推动力。