共查询到20条相似文献,搜索用时 250 毫秒
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本文从连栋温室供热系统的节能要求出发,重点研究了常用的热水供热系统光管散热管道的热工性能在涂辐射涂层前后性能变化,及提高散热管道辐射换热特性对温室内热环境的影响,为设计经济合理的连栋温室提供依据。 相似文献
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针对传统生物质墙体存在集热蓄热差的热工问题,提出一种以太阳能为热源的集成管道生物质蓄热墙体,通过建立对比实验模型,分别测试墙体系统及室内物理环境参数,研究2种模型存在的热效率差异,并对实验组墙体系统进行供热性能分析。结果表明:所提出的集成管道生物质墙体系统具有良好的集热、蓄热性能;管道流系统循环控制策略应适应当地气象条件以优化系统供热效率;集成管道生物质蓄热墙节能率可达79.3%,经济效益明显,在生物质能与太阳能富集地区具有广泛应用前景。 相似文献
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就我们使用新的行业标准《城市热力网设计规范》(GJJ34—2002)一年多的体会和设计应注意的问题,定出本。本就采暖热指标,空调热、冷指标,生活热水指标的先取;采暖全年热耗量的计算;采暖供回水温度的选择;热网补给水的水质;工业用汽凝结水水质及排放标准;不锈钢设备氯根的腐蚀;采暖供热保证率;供热调节;水力计算的压力工况;热网循环水泵吸入侧压力的选择;管道敷设要求;直埋管道;阀门材质选择;对中继泵站与热力泵站的设计要求;热力站热网设备布置;对蒸汽热网热力站的设计要求;对保温的要求;对热工检测与控制要求等问题进行了分析,提出了编的看法和应注意的问题,并对有关规范条做了介绍,并论述了热力网设计规范与火电厂设计技术规程有关条的矛盾。 相似文献
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本文详细论述了玻璃钢管道的性能、原材料、制作工艺,对玻璃钢管道在地热供热系统中的特性进行分析研究,给出该管道在工程安装中应遵循的原则及补救措施。 相似文献
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针对我国工艺锅炉的能源消耗状况、管道的有效利用、管道保温达到的性能指标分析及热水供暖的技术要求与供热系统和热网设计中的节电措施,进行了技术分析并提出了解决对策,同时介绍降低能耗的几种方式。 相似文献
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热力管道地下直埋敷设技术,近年来在我国发展很快。其中温度130℃以下热水管道的直埋,已广泛成功地应用于城市供热管网建设中;蒸汽管道地下直埋敷设技术,由于其供热介质的特殊性,虽然在我国还处于研究开发和初步应用阶段,但也已有为数不少的应用实例。 相似文献
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《International Journal of Hydrogen Energy》2023,48(7):2510-2517
Providing the heating system with coal in greenhouses causes harmful results in terms of carbon emissions. In this study, analyzes were performed to meet the electrical energy required for the heating system with a heat pump from a solar photovoltaic-hydrogen system. For floor area 25000 m2 where greenhouses the required energy is obtained directly from hydrogen without using a heat pump 3000 m2 solar panel area required. The use of a heat pump reduces energy needs but it is also not feasible for large greenhouses. For convenience, a solar photovoltaic-hydrogen-heat pump system analysis was also made for 1000 m2 floor area greenhouses and it is found that the 24 m2 solar panel area is adequate in terms of meeting energy demand. Using a solar-hydrogen-heat pump system reduces carbon emissions by 86.5 tons per 1000 m2 floor area greenhouse. Considering the hydrogen storage system becomes unfeasible. We normalized the greenhouse floor area to 1 m2 and proposed reference values for hydrogen to be produced in 1 h, storage, and PV area. In addition, an analysis was made for the use of hydrogen energy for greenhouses that do not require a heating system and only work with a water pump. 相似文献
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差压控制器在热水供热系统的实际应用 总被引:1,自引:0,他引:1
热力系统水力失调问题严重影响着供热系统正常运转。本文对自力式差压控制器原理进行分析和论述,通过地区热网的热平衡改造实际应用,有效解决了长期困扰热力系统水力失调的问题。 相似文献
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In the present study, an analytical approach governing the temperature rise in the solid pipe and fluid is presented. The entropy analysis in the fluid system due to heat transfer is introduced to obtain the integrated entropy generation in the system. Coolanol, water and mercury are selected as fluids while copper and steel are considered as pipe materials. In order to simplify the analysis, the heat transfer coefficient at solid–liquid interface is kept constant during the calculations. It is found that the fluid temperature rise in the early heating period and the integrated entropy generation in the fluid system is lower in the case of a copper pipe. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Energy‐efficient design of greenhouse for Canadian Prairies using a heating simulation model 下载免费PDF全文
Greenhouses in northern climates require a large amount of supplemental heating for growing crops in winter seasons, so energy‐efficient design of greenhouses based on local climate is important to minimize the heating demand. In this study, greenhouse design parameters including shape, orientation, the angle of the roof, and width of the span have been studied for the conceptual design of conventional greenhouses for Canadian Prairies using a heating simulation model. Five different shapes of greenhouses including even‐span, uneven‐span, modified arch, vinery, and quonset shape have been selected for the study. The simulation results proved that the uneven‐span gable roof shape receives the highest solar radiation, whereas the quonset shape receives the lowest solar radiation. However, the quonset shape greenhouse requires about 7.6% less annual heating as compared to the gable roof greenhouse, but the quonset would not be adopted as multispan greenhouses. Therefore, the gable roof greenhouse is considered as energy efficient for the multispan gutter connected greenhouses whereas quonset shape as a free‐standing single‐span greenhouses. In high northern latitudes, the greenhouse with east‐west orientation is more energy efficient from heating and cooling point of view when the length‐width ratio of the greenhouse is more than 1. The heating energy saving potential of the large span width in single‐span greenhouses is relatively higher as compared to the multispan greenhouses. 相似文献
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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。 相似文献
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针对既有建筑的节能改造,探讨了建筑改造后采暖热媒参数设定问题。本文主要阐述了供暖系统形式为单管顺流式系统的节能改造建筑,在由于节能改造而导致建筑物热负荷减小的情况下,采暖供回水温度取值的调整问题。从热平衡方程式出发,推导出了节能改造建筑供回水温度的计算公式,为该类建筑的采暖运行提供了理论上的依据。 相似文献