家用空调制热技术发展趋势分析

随着空调使用要求的不断升级,家用空调制热相关方面功能也越来越受到用户的关注。从家用空调产品制热参数的变化以及制热使用时众多痛点问题的解决方式途径出发,基于产品信息、专利资料、产品卖点等分析了家用空调制热技术研究趋势,为日后家用空调产品的研发提供技术参考。分析数据表明:制热节能以及除霜控制仍是技术研究的主要方向,暖足功能符合人体理想的采暖方式,未来必将成为产品的一大卖点;加湿技术能够解决空调采暖干燥的痛点,亦会获得用户的认可。

太阳能光热空气源热泵制热技术研究综述

有利于节能减排及国家能源结构战略性调整的太阳能光热空气源热泵,作为重要的太阳能结合空气能制热技术,在直膨式、水箱换热式、相变蓄热式等系统结构的研发方面,已经取得长足进展。直膨式太阳能热泵的制热性能系数,相比于常规空气源热泵可提高25%以上,相当于电热水器的3倍以上、冷凝式燃气炉的1.3倍以上;水箱换热式制热系统相比常规的热水及空调系统的全年平均节能率,可达25%以上;相变蓄热式系统的制热性能系数普遍可达3.31以上。面对"十三五"阶段全国加速城镇化的新常态,研究路线需要更加偏向适用于高层建筑用户,即将庞大、分散的系统结构集成一体化,以适应广大高层建筑用户垂直、狭窄的外立面安装环境。

碳中和视阈下的工业余热回收利用关键技术

随着社会经济的迅速发展,节能环保的地位逐渐提升。余热作为一种非常典型的二次能源,大量产生于工业生产中,利用关键技术能实现对余热的回收再利用,切实实现节能减排。基于碳中和视阈,对工业余热的自身特点进行概述,并详细探讨了工业余热回收利用的关键技术,希望可以为工业余热回收利用技术的发展提供参考。

多联机热回收技术应用研究

暮介绍了多联机热回收及同时制冷制热技术的应用前景和意义，说明了该技术所带来的效益和优势：实现同一套系统同时制冷制热功能，提升系统的能效，减少系统能耗和碳排放，缓解居住环境的热岛效应等。同时阐述了目前常用的多联机热回收及同时制冷制热技术的实现方法：三管制热回收多联机技术、两管制热回收多联机技术和四管制热回收多联机技术。通过对3种技术的优缺点进行比较分析，指出三管制热回收技术具有最佳的综合优势和效益。

新能源汽车热管理系统技术的应用分析

在我国经济建设的飞速发展下,国家对于相关新能源领域的发展方向和质量问题提高了关注度。在这样的发展趋势影响下,这一行业的实际发展问题越来越受到社会各界人士的广泛关注和热烈讨论。本文主要就新能源汽车领域中有关热管理系统技术应用的相关问题进行简要分析,希望能够帮助相关技术人员在进行实际的热管理技术创新过程中作出更多的思考,促进我国新能源汽车整体热管理技术的进一步发展,为整体提升新能源汽车的基础设施质量优化打下了更为坚实的基础。

空气源热泵机组在烘干领域的应用

空气源热泵的工作原理是遵循逆卡诺循环理论,利用空气中所蕴含低温热源,通过系统的高效集热整合后成为高温热源,用于供暖和供应热水,是一种高效的节能环保制热技术。空气源热泵机组运用到烘干技术中,可以节约成本降低能源损耗。

The research on the thermal destruction of environment and controlling techniques of the No.4 outcrops fire in Haibaoqing

The coal fire is one of very serious disasters in natural, not only amount of coal resources was burned and some ecological environment problems such as ground subsidence, acid rain, pollution and vegetation died were caused serious. The No.4 coal seam outcrops fire in Haibaoqing was take as research object, based on the existing theory of mechanism and characteristics of coal outcrop fires, a new fire-fighting composite gel is applicated which fits in with extinguishment of outcrop coal fires well. The technology has many advantages in extinguishing coal fires including isolating the coal from oxygen and lowering the temperature of the high-temperature coal and rock. The structure and chemical composition as well as fires-fighting properties of the composite gel is analyzed profoundly, as a result, reduce and stop the environment destruction caused by the coal fire.

Bayesian networks modeling for thermal error of numerical control machine tools

The interaction between the heat source location, its intensity, thermal expansion coefficient, the machine system configuration and the running environment creates complex thermal behavior of a machine tool, and also makes thermal error prediction difficult. To address this issue, a novel prediction method for machine tool thermal error based on Bayesian networks (BNs) was presented. The method described causal relationships of factors inducing thermal deformation by graph theory and estimated the thermal error by Bayesian statistical techniques. Due to the effective combination of domain knowledge and sampled data, the BN method could adapt to the change of running state of machine, and obtain satisfactory prediction accuracy. Ex- periments on spindle thermal deformation were conducted to evaluate the modeling performance. Experimental results indicate that the BN method performs far better than the least squares (LS) analysis in terms of modeling estimation accuracy.

Heat Transfer in Nucleate Pool Boiling of Binary and Ternary Refrigerant Mixtures

Heat transfer coefficients in nucleate pool boiling were measured on a horizontal copper surface for refrigerants, HFC-134a, HFC-32, and HFC-125, their binary and ternary mixtures under saturated conditions at 0.9MPa. Compared to pure components, both binary and ternary mixtures showed lower heat transfer coefficients.This deterioration was more pronounced as heat flux was increased. Experimental data were compared with some empirical and semi-empirical correlations available in literature. For binary mixture, the accuracy of the correlations varied considerably with mixtures and the heat flux. Experimental data for HFC-32/134a/125 were also compared with available correlated equation obtained by Thome. For ternary mixture, the boiling range of binary mixture composed by the pure fluids with the lowest and the medium boiling points, and their concentration difference had important effects on boiling heat transfer coefficients.

Improvement of surface corrosion resistance for magnesium alloy by combining thermal spray and cast-infiltration

The present work focuses on a new method combining cast-infiltration with thermal spraying technology to improve the surface corrosion resistance of magnesium alloy.A zinc-based alloy layer was fabricated on the surface of AZ91D magnesium alloy. The microstructure of the layer was characterized by scanning electron microscopy equipped with an energy dispersive X-ray spectroscopy(EDS).The phase constituent of these alloys was identified by X-ray diffractometry(XRD).The analysis results reveal that a zinc-based alloy layer with a thickness of 700μm can form on the surface of AZ91 alloy matrix.The layer is composed of Mg7Zn3,MgZn and a small amount of α-Mg solid solution.The results indicate that the corrosion-resistance of the specimen with a zinc-based alloy layer is much better than that of the specimen without the layer after being immersed in 5%NaCl solution for 240 h, and the layer is more protective for the AZ91 alloy.

Ageing Assessment, Condition Inspection and Lifetime Evaluation for Safety Related Fuse in Nuclear Power Plant

This paper presents the ageing mechanism of fuse in nuclear power plant in detail. Metal Electromigration is identified as the dominant ageing mechanism. On this basis, the dominant status indicators, temperature and resistance of fuse were ensured, and current-temperature curve was proposed. The infrared thermal imaging technology was used to inspect the ageing condition and prove the current-temperature curve. Finally, the accelerated ageing testing was conducted abiding by the dominant ageing mechanism, and the lifetime was evaluated.

Study and practice of the controlling technique on heat-harm during the tunneling in Zhaolou mine

This paper proposes the cooling system type and cooling equipment type which are deep mine with high temperature during the construction,and presents auxiliary cooling measures making up duct temperature rise since compression and heat transfer temperature rise. The cooling system designed against Zhaolou mine's ground temperature and weather conditions,with its sprinkler room handling an average temperature difference up to 19.5～23.8 ℃,and the average enthalpy difference could reach 48.4～60.7 kJ/kg. At the same time,it gets a series of basic data used for mine construction during the cooling system design and equipment selection according to the measured results; using the analysis software Matlab,it obtains the change relations between the temperature of sprinkler room and fan export supply air temperature,wind casing temperature rise and fan export supply air temperature,working face temperature and supply air temperature,used for the mine cooling which has the similar conditions.

Energetic and Exergetic Analysis of Organic Rankine Cycle Powered by Hot Geothermal Water

The paper presents an investigation of energy and exergy analysis of an existing ORC （organic rankine cycle） unit powered by hot geothermal water. The validated model of this unit was used to examine 25 refrigerants belonging to different chemical compositions. The study revealed that R141b and R123 produced the best net power, energy efficiency, and exergy efficiency, whereas R125 was the lowest. Hydrofluorocarbons （except R143a）, hydrocarbons, and inorganic reflected attractive energy and exergy efficiencies. All investigated mixtures gained low performance compared with other studied candidates. The R245ca was the best among the hydrofluorocarbons studied refrigerants, and R501 was the best among the mixture refrigerants. Furthermore, within the ORC system, the evaporator was found to have the highest exergy destruction and the refrigerant pump was the lowest.

Synthesis of molybdenum disulfide/reduced graphene oxide composites for effective removal of Pb(Ⅱ) from aqueous solutions

In this work, a facile method was adopted to synthesize molybdenum disulfide/reduced graphene oxide （MoS2/rGO） composites through an c-cysteine-assisted hydrothermal technique, The as-prepared MoS2/ rGO composites were firstly applied as adsorbents for efficient elimination of Pb（Ⅱ） ions. Batch adsorption experiments showed that the adsorption of Pb（Ⅱ） on MoS2/rGO followed pseudo-second-order kinetic model well. The adsorption of Pb（Ⅱ） was intensely pH-dependent, ionic strength-dependent at pH 〈 9.0 and ionic strength-independent at pH 〉 9,0, The presence of humic acid （HA） enhanced Pb（Ⅱ） adsorption obviously. The MoS2/rGO composites exhibited excellent adsorption capacity of 384.16 mg g 1 at pH 5.0 and T = 298.15 K, which was superior to MOS2 （279.93 mg g 1） and many other adsorbents. The thermodynamic parameters suggested that the adsorption process of Pb（Ⅱ） on MoS2/rGO composites was spontaneous （zSG＂ 〈 O） and endothermic （△H 〉 0）. The interaction of Pb（Ⅱ） and MoS2] rGO was mainly dominated by electrostatic attraction and surface comple^ation between Pb（Ⅱ） and oxygen-containing functional groups of MoS2]rGO. This work highlighted the application of MoS21rGO as novel and promising materials in the efficient elimination of Pb（Ⅱ） from contaminated water and industrial effluents in environmental pollution management.