燃气红外线辐射供暖系统在工商农业领域中的应用

通过对高大空间供暖方式的技术分析,提出燃气辐射供暖是解决高大空间供暖的有效途径,并介绍了这种供暖方式的原理、工作方式。     

红外供暖应用

红外辐射采暖技术是被世界公认的堪称最为现代化的供暖方式，本文将于壁桂式建筑供暖辐射器的各自单独供暖及其联合配套供暖技术.进行介绍。     

地热供暖

<正>地热能供暖包括地热井供暖和地源热泵两种方式,无论是哪一种方式,都是利用中浅层的地热资源,为建筑物提供可以长期利用的热量或冷量。地热能供暖不会像化石能源那样带来碳排放导致的环境污染,也不会像一般的空气源热泵一样将多余的热量排出室外从而导致热岛效应,是十分清洁     

蒸汽供暖和热水供暖方案比较和应用

办公室和厂房供暖常采用蒸汽供暖或热水供暖。结合实际情况分析比较了两种供暖方式的优缺点。蒸汽供暖一次性投入较小,但使用维护费用较大;热水供暖和蒸汽供暖相比需增设一套热水循环装置、回水池和回水管路,但运行费用相对较少,且可最大程度地减少跑、冒、滴、漏现象的发生,从而可大大提高设备和材料的利用率,降低成本,最终起到节能降耗的作用,应广泛推广和应用。     

浅谈供暖方式改革

我国北方地区，每到冬季，都需要供暖。现有的供暖方式，有热供暖和电供暖两种。这两种供暖方式，各有利蔽，都不是最好的，需要改革。改革的方向，是建立以化学发电为热源的发电供热循环系统，在家庭、楼群、居民小区或商业区，建立发电供热站。     

一种新型的供暖方式——地板辐射供暖

简要介绍了地板辐射供暖系统的原理,并与传统的供暖方式作对比,被认为是目前最理想的一种供暖方式,市场前景广阔。     

传统建筑供暖的变革新思路——电热膜供暖

介绍了北方地区锅炉供暖热水采暖系统,耗费大量钢材、煤炭、水等普遍存在着资源浪费、环境污染、供暖费难收缴等问题,针对以上问题,提出采用新的供暖方式,电热膜采暖技术,具有经济、节能、运行管理的可推广性。     

浅谈地板辐射供暖技术

地板辐射采暖是一种舒适、环保、节能的现代供暖方式。在诸多供暖技术中,地板辐射供暖技术无疑是热舒适度最好的一种供暖方式。在设计中,不但要对地面构造、热媒、热管系统及分集水器进行合理的设计,还要分别对负荷、散热量和热管水力进行系统的计算,同时加以正确的选材与施工才能充分发挥出地板辐射供暖的技术的优势。     

争议南方供暖

当前，南方是否供暖已基本达成共识，但在供暖方式上存在巨大分歧。企业抢滩南方市场后为何难以落地，又面临怎样的风险？     

间歇供暖与节能

<正> 我国采暖面积大,各地的气象条件、采暖习惯、资源状况不尽相同,因而,间歇供暖仍被有些地区采用,特别是在非最冷季节和采暖过渡地区,利用连续供暖设备进行间歇供暖,较多采用。间歇供暖大体可分为两种,一种是住宅式间歇供暖,这种供暖要求室温日平均值等于或接近室内计算温度,因此是不节能的。另一种是办公楼式间歇供暖,这种供暖方式因其室温日平均值低于计算温度,因而是可以节能的。比如,办公楼、公用建筑,夜间不     

Key parameters and optimal design of a single-layered induction coil for external rapid mold surface heating

Setting high mold temperatures for injection-molding plastics facilitates favorable flow conditions for filling cavities with melted materials and provides an esthetically pleasing surface as well as a high replication rate of high-quality products; however, the cooling times are typically prolonged. Electromagnetic induction heating incorporating surface heating instead of conventional volume heating for mold-heating processes is advantageous because it provides a rapid heating time and a reduced cooling time, is environmentally friendly, and saves energy; therefore, it has been adopted in various variotherm injection-molding systems. Although previous studies have discussed how induction heating is influenced by major factors, such as the number of coil turns, working frequency, and heating distance, few studies have investigated other crucial factors, such as the thickness of the heated target and the position of the induction coil. In this study, the effects of the thickness of a heated target, pitch of coil turns, heating distance, position of the induction coil, working frequency, and waiting time on the heating rate and temperature uniformity of induction heating on a mold surface by using a single-layered coil were analyzed. In addition, the Taguchi method and principal component analysis were applied to determine the optimal combination of control factors for achieving a high heating rate and low temperature deviation. Both simulation and experimental results indicated that the thickness of a heated target plays a crucial role in affecting the heating rate; specifically, a thicker workpiece slows the heating process and generates rapid heat dissipation after induction heating. Moreover, the position of the induction coil exerts the most notable effect on heating uniformity.     

光照资源富集区太阳能集中供热系统容量配置及热网管径协同设计优化研究

针对常规太阳能供热系统优化设计中太阳集热供热站设计与供热管网设计相互分离,供热管网热传输过程中热损失难以精准计算的问题,建立太阳能集中供热系统容量配置及热网管径协同优化模型,以系统全生命周期成本最小为优化目标,采用遗传算法求解,并通过具体算例与常规优化方法以及工程设计方法的计算结果进行对比分析。结果表明,利用协同优化模型进行太阳能集中供热系统设计,能够有效避免设计系统太阳能保证率偏小以及供热管网比摩阻不满足规范要求的现象。针对具体算例,当太阳能保证率由50%增至100%时,系统最优最低供水温度从60℃降至45℃;随着太阳能保证率的升高,系统单位太阳集热器面积所匹配的储热水箱体积增大,而系统供热管网管径保持不变。     

半桥型IGBT移相调功感应加热电源

介绍工作频率为３０－６０ｋＨｚ、功率５ｋＷ串联准谐振移相调功感应加热电源的工作原理及实验仿真结果。控制电路采用ＬＥＭ电流传感器和ＣＤ４０４６集成锁相环实现频率跟踪和移相调功，具有电路简单、效率高、体积小和成本低等优点。     

太阳能地面采暖系统蓄热水箱容积分析

通过分析太阳能采暖系统所需蓄热鼍与建筑热负荷、太阳能集热量日变化规律之间的关系,得出太阳能采暖系统所需蓄热水箱容积的理论算式.根据拉萨、银川、西宁、西安等地的太阳辐射强度及建筑热负荷的日变化规律,模拟得出系统所需蓄热量变化规律;并对各种蓄热温差下对应的蓄热水箱容积进行了模拟分析,结果表明:太阳能采暖系统所需蓄热量随太阳集热器的集热量与建筑热负荷之间的差值增大而增加;蓄热水箱容积随蓄热温差增大而减小,当蓄热水温达到80℃时,在各种地面采暖系统取水温度下,单位集热器面积所需蓄热水箱容积趋于相等.     

垃圾焚化余热锅炉受热面设计特点

垃圾锅炉设计成多烟道结构,体积庞大,受热面积数倍于普通锅炉,且负荷变化率不小于2。图示出这种锅炉特有的布置于高温烟气区的一次交叉流动空气预热器管壁温度场。     

Laser heating: jet emanating from laser induced cavity

Laser heating of steel surface and cavity formation during laser irradiation pulse are investigated. The recession of the solid surface due to melting and evaporation is modeled using an energy method. Jet emerging from the laser induced cavity and expanding into stagnant water, resembling laser shock processing, is also simulated. Governing flow equations are solved numerically using a control volume approach employing a moving mesh in the solution domain. This is because of the recessing surfaces of the vapor, liquid and solid phases during the heating pulse. It is found that mushy zone size at liquid–vapor interface is larger than that of at solid–liquid interface. Expansion of the vapor jet, emanating from the cavity and expanding into stagnant water ambient, is high in the axial direction in the early heating period, and as the time progresses the radial expansion of the jet becomes visible due to pressure build up in the jet frontal area. Considerably high recoil pressure is developed in the cavity due to high recession velocity of cavity surface and expansion velocity of vapor jet.     

Étude numérique de l'ébullition en convection mixte dans une couche poreuse verticale

By using an enthalpic method (two-phase mixture model), we have studied numerically boiling with mixed convection in a vertical porous layer with a discrete heating. Liquid is injected at the top face. Finite volume method is used for numerical resolution of equations of volumetric enthalpy and pressure. Results giving time–space evolution of temperature, pressure, velocities of the fluids and evaporated volume are presented and analyzed. Parametric studies to assess the effects of inlet velocity, imposed heat flux and permeability, were performed. Results show that boiling is important if the effects of both, natural and forced convections are similar. The evaporated volume will decrease at high values of intrinsic permeability of porous medium or at high values of inlet velocity.     

太阳能-生物质能联合供暖系统研究

为研究太阳能-生物质能联合供暖系统的供暖效果,通过正交实验设计了多种工况,并利用TRNSYS软件对不同工况进行模拟计算得出了最优工况,按照最优工况参数进行实验研究。结果表明：在集热器面积21 m²、生物质锅炉容量10 kW、集热水箱容积1.9 m³、谷电蓄热水箱容积1 m³的工况下,联合供暖系统具有良好的热舒适性,系统平均供热效率为68.70%。     

Review of the phase change material (PCM) usage for solar domestic water heating systems (SDWHS)

The shortage in energy resources combined with the climb in greenhouse emissions is the main incentive beyond the deployment of solar energy resource in various applications. One of the most successful applications is the utilization of solar energy in the domestic water heating systems (DWHS) because 70% of the consumed energy in the residential segment is utilized for space heating and appliances in cold climates 1 . However, the full deployment of solar energy in domestic water heating is only possible when an energy storage system with acceptable price is available. Recently a new tendency for deploying phase change materials (PCMs) as an energy storage system is introduced in several solar DWHS. These systems are known as integrated PCM in solar DWHS and offer several advantages including high storage capacity, low storage volume, and isothermal operation during the charging and discharging phases. The present study reviews various techniques utilized for integrating the PCM in solar water heating systems and the utilized methods for enhancing the heat transfer characteristics of the PCM through the usage of extended surfaces and high conductive additives. Copyright © 2017 John Wiley & Sons, Ltd.