常压与承压热水锅炉供暖系统供暖效果的对比分析

依据供暖系统热平衡和散热器的传热原理,在对常压锅炉与承压锅炉热水供暖系统和供暖参数进行对比的基础上,分析了二者的供暖效果,通过对系统的简化处理,计算出了在相同条件下两种不同系统所能达到的室内供暖温度差异,揭示了常压锅炉供暖系统供暖效果不佳的内在原因,并对常压锅炉供暖系统的设计提出建议.     

燃煤锅炉的除尘脱硫与节能

针对供暖锅炉的运行和管理现状,分析了环境污染和能源浪费的原因,从技术可行性、运行管理和供暖工程设计等方面提出了改进的措施．     

微机监控、变频调速是供暖锅炉节能的有效途径

文章重点探讨了供暖锅炉节能运行的正确途径及相应的监控系统。该系统采用51系列单片微机和高性能马达变频器结合的设计方案,对锅炉运行中的温度、压力、流量、煤耗、锅炉出力、热效率等十二项参数进行实时检测和巡回显示,根据供暖质量要求,自动调节鼓风、引风及炉排速度,并以合理的风煤配比,实现对锅炉燃烧状态的最佳过程控制。     

锅炉供暖现状及运行节能技术措施

由于历史原因和国力所限,锅炉供暖和热力供暖共同发展、互为补充的局面在我国还将长期存在。锅炉供暖节能存在着巨大的潜力,多年来形成的高能耗问题,原因在于缺乏统一规划、设计层层加码、管理不科学、设备质量差。在着重分析运行管理方面的问题之后,指出了多项运行节能技术措施以及实用效果。     

无压锅炉供暖系统设计中几个问题的探讨

针对无压锅炉供暖系统设计中有关循环水泵扬程的选择、循环水泵的设置高度及是否设置膨胀水箱等问题从理论和实践上进行了探讨,得出了可供设计人员实际应用的计算公式,介绍了几个关键问题的处理方法,澄清了一些模糊认识。这对无压锅炉供暖系统的设计、计算及运行管理都具有一定的实际意义。     

浅析供暖锅炉的常见故障及维修策略

本文主要以实际工作中所遇到的燃煤供暖锅炉的常见问题和故障作为主要阐述对象,并结合工作经验,提出了一些供暖锅炉故障维修和日常保养所需注意的问题。     

基于PLC的供暖锅炉监控系统设计

本文设计了一套基于PLC和变频调速技术的供暖锅炉控制系统。系统通过变频器控制电动机的启动、运行和调速。上位机监控软件采用三维力控ForceControl 6.1进行设计,主要完成系统操作界面设计,实现系统启/停控制、参数设定、报警联动、历史数据查询等功能。下位机控制程序采用西门子公司的STEP7编程软件进行设计、参数设定、循环泵控制和其余电动机的控制。     

采用生物质混燃的燃煤锅炉运行工况分析

为解决东北地区生物质混燃供热锅炉运行中存在的技术问题,以长春某供热公司10 t燃煤锅炉为研究对象,采用理论分析与对比试验相结合的研究方法,确定适合的燃料配比,并进行技术与经济性分析.研究结果表明：在秸秆与煤的混合比为1∶10时,生物质混燃供暖锅炉的经济性与技术性最佳.     

锅炉运行对湿式脱硫系统性能影响的研究

研究了锅炉燃烧和运行工况变化对湿式石灰石脱硫系统性能的影响,建立了数学模型,并且对液气比、pH值、SO_2浓度等影响因素进行了单元和多元回归分析,为湿式脱硫系统的设计、运行及锅炉燃烧和运行对其性能影响的预测提供了参考依据。     

浅析锅炉运行效率的提高

锅炉运行效率是锅炉的实际效率,锅炉间歇运行和锅炉实际燃煤与设计燃煤不相符,是锅炉运行管理中造成锅炉运行效率低的主要原因,本文提出了在锅炉运行管理中提高运行效率的有效措施和方法。     

热管技术研究、发展与工业应用

介绍了一些热管技术在工程的典型应用，包括废热回收设备和工业过程设备．水碳钢热管技术在许多工程领域都得到了成功应用,如：用于废热回收、节能与环境保护的空气预热器和废热锅炉．液态金属高温热管技术在过程装备得到了广泛应用。高温热空气发生器和热管技术在化学反应器中也能发挥作用，如在氨合成塔中的应用．热管技术的成功应用是建立在热管技术的基础研究之上的，这些研究包括：热管内汽液两相流动与传热、热管传热极限、热管传热强化和热管材料相容性与热管的寿命等方面理论和实验研究．高效传热与传质的热管设备在许多工程应用领域将会得到越来越重要的应用．     

Modeling and optimization of rotary kiln treating EAF dust

Electric arc furnace （EAF） dust from steel industries is listed by the United Sates EPA as a hazardous waste under the regulations of the Resource Conservation and Recovery Act due to the presence of lead, cadmium and chlorine. The disposal of the approximately 650000 t of EAF dust per year in the U.S. and Canada is an expensive and unresolved problem for the majority of steel companies. The Waelz process has been considered as the best process for treating the EAF dust. A process model, combined thermodynamic modeling with heat transfer calculations, has been developed to simulate the chemical reactions, mass and heat trans- fer and heat balance in the kiln. The injection of air into the slag and the temperature profile along the kiln have been modeled. The effect of （CaO＋MgO）/SiO2 on the solidus temperature of slag has also been predicted and discussed. Some optimized results have been presented.     

2×200MW核供热堆供热系统经济性问题探讨

文中对区域锅炉房供热系统与以壳供供热堆为主热源、燃煤锅炉房为调峰热源的核供热系统作了较为深入系统的经济对比分析,探讨了核供热堆的临界比投资,以及核供热系统的最佳供热系数和最佳计算温度。     

Application of entransy dissipation based thermal resistance to design optimization of a novel finless evaporator

Entransy has been applied and studied in a broad range of heat transfer optimizations recently. Current study proposes the entransy of evaporators to conduct the optimization of heat exchangers in heating, ventilation, air conditioning and refrigeration systems. A novel finless bare tube heat exchanger was studied using a validated heat exchanger modeling tool. The capacity based optimization and entransy dissipation based thermal resistance were used and compared. The applicability of using entransy dissipation based thermal resistance in this type of heat exchanger optimization has been discussed. It has been demonstrated that minimizing entransy dissipation and maximizing capacity are equivalent to optimizing evaporators with fixed flow rates and different when optimizing evaporators with variable flow rates and the deviation is negligible when heat exchanger capacity is small (～1 kW) and more obvious as heat exchanger capacity increases. Thus entransy dissipation based thermal resistance could be used as an alternative optimization index to capacity for evaporators with fixed flow rate and small capacity evaporators with variable flow rates and should be used individually with capacity as an optimization index for evaporators with large capacity and variable flow rates.     

孔口面积及热源位置对热压通风影响的模拟研究

利用流体力学计算软件Airpak对单热源民用建筑房间的热压通风进行了模拟。给定热源体总热量,在改变上下部孔口面积比例的情况下,分析各模拟情况下室内热压通风的中和面高度、有效热量系数、通风量及排出余热量等特征参数的变化规律;在孔口大小固定的情况下,研究热源体水平位置同孔口间距改变时热压通风的室内温度场、流场、热源表面温度等参数的变化规律。研究结果表明:上下部孔口开口面积相差不大时,房间内的热压通风效率最佳;下部孔口面积略大于上部孔口面积时,有效热量系数m处于较低的范围内,且增大某一孔口面积,中和面会朝着该孔口方向移动;热源体越靠近下部孔口,越有利于热源散热。     

太阳能与地埋管热泵联合采暖实验

为了考察太阳能光热系统的蓄热能力,以及太阳能地埋管热泵联合采暖空调是否满足建筑物能量供给,针对一栋220 m2的建筑物,建立了一套太阳能地埋管热泵联合采暖空调系统.以冬季采暖负荷作为建筑物的能量需求,在此基础上配置太阳能和地埋管系统.实验结果表明:通过太阳能光热跨季节采暖蓄热,可以使土壤温度提高3℃,制热机组能力提高8%,太阳能光热和地埋管热泵系统联合采暖切实可行.     

普通单元式住宅的室内热环境及能耗研究

利用动态模拟的方法,分析了在固定室内供热量时,室温的逐时变化情况;以及在室温为固定值时,能耗的逐时变化情况,为室内热舒适及节能的研究提供了一定的理论依据。     

蒸汽远程测控系统的研究与应用

针对热网系统的蒸汽生产和使用过程进行准确测量与控制,采用计算机技术,通信技术及流量检测技术对蒸汽远程测控系统进行了研究,研制了一套分布式上下位机蒸汽远程测控系统,上位机采用高性能微型计算机,ＨＷ－ＲＷＢ高可靠性调制解调器,下位机采用以Ｉｎｔｅｌ８０５１为核心的智能计量装置,实现了对热网蒸汽参数的实时远程计量监测,建立了热网蒸汽参数的实时数据库,根据热网用户对蒸汽参数的要求,采用优化估计的方法建立热     

Research trend of cascade heat pumps

Most commercial and industrial facilities require very low temperatures for refrigeration and high temperatures for space heating and hot water purposes. Single stage heat pumps have not been able to meet these temperature demands and have been characterized by low capacities and coefficient of performance(COP). Cascade heat pump has been developed to overcome the weaknesses of single stage heat pumps. This study reviews recent works done by researchers on cascade heat pumps for refrigeration, heating and hot water generation. Selection of suitable refrigerants to meet the pressure and temperature demands of each stage of the cascade heat pump has been discussed. Optimization of design parameters such as intermediate temperature(low stage condensing and high stage evaporating temperatures), and temperature difference in the cascade heat exchanger for optimum performance of the cascade heat pump has been reviewed. It was found that optimising each design parameter of the cascade heat pump is necessary for maximum system performance and this may improve the exergetic efficiency, especially of cascade refrigeration systems, by about 30.88%. Cascade heat pumps have wider range of application especially for artificial snow production, in the supermarkets,for natural gas liquefaction, in drying clothes and food and as heat recovery system. The performance of cascade heat pumps can be improved by 19% when coupled with other renewable energy sources for various real time applications. Also, there is the need for much research on refrigerant charge amount of cascade heat pumps, refrigerant-refrigerant heat exchangers to be used as cascade heat exchanger, cascade heat pumps for simultaneous cooling, heating and hot water generation and on the use of variable speed compressors and their control strategies in matching system capacity especially at part load conditions.     

内置螺旋线圈换热管换热分析及数值模拟

概述了螺旋线圈装置的强化传热原理。通过建立光管和内置螺旋线圈换热管的三维流动模型,利用Fluent软件以黏性流体变压器油为研究对象对换热管内速度场、温度场、压力场以及换热过程进行了数值模拟。对比两种模拟结果表明,内置螺旋线圈的换热管内流体流动比较复杂,流体在近壁面处呈明显的螺旋流动,流体的径向速度和切向速度都有提高。总的来说,换热管内布置了螺旋线圈以后流体在其中的流动比在光管内有更强的湍流度,且能够打破流体的速度边界层,增强了流体的对流换热,极大提高了传热系数。