共查询到18条相似文献,搜索用时 824 毫秒
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本文首先论述了变频技术在高精度恒温恒湿空调机中应用的可行性,设计并制造了实验样机.而后提出了一种新型的分阶段电子膨胀阀一变频压缩机同步自适应PID控制方式,阐述了其控制原理,并成功应用于实验样机中.最后通过实验研究了变频恒温恒湿空调机温湿度控制精度特性,结果表明:变频恒温恒湿空调机无论是在恒定热湿负荷下还是热湿负荷阶跃干扰下,均能实现室内环境温度控制精度±0.5℃以内,相对湿度控制精度±3%以内,并能够长时间稳定运行.同时,通过实验论证了分阶段电子膨胀阀--变频压缩机同步自适应PID控制方式能够很好地缓解控制上的延迟和超调现象. 相似文献
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恒温恒湿空调系统的设计与研究 总被引:2,自引:0,他引:2
以冷藏陈列柜标准测试台为例,对恒温恒湿空调系统进行了设计和运行调试分析,提出恒温恒湿空调系统设计需注意的一些方面,如热湿负荷特点、气流组织、系统的风量等,指出空调设备中制冷系统变频调节技术的使用和温湿度分别控制等能够有效提高系统温湿度的精度。 相似文献
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从排风柜变风量控制、实验室压力控制、风机变频控制等方面阐述了变风量控制系统在化学实验室暖通空调系统中的应用。以化学合成实验室为例,结合同时使用率和运行模式,对不同运行工况下的变风量系统进行了对比,分析了变风量控制系统在初投资、节能减排方面的优势。 相似文献
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针对上海某档案库房的地源热泵恒温恒湿空调系统,研究了冬夏季节不同室内设计温度对系统运行特性的影响。实验结果表明,冬夏季节的两种不同工况均能满足档案库房室内温湿度的控制要求。理论分析结果表明,夏季工况时,随着室内设计温度的升高,地源热泵恒温恒湿空调机组的COP基本保持不变,约为5.0,但减少了向土壤的排热量;冬季工况时,室内设计温度升高时,地源热泵恒温恒湿空调机组的COP略有升高,并且增加了从土壤中的取热量。综合考虑系统的节能性、稳定性以及档案保存的特殊性,夏季室内设计温度建议为22℃~24℃,冬季室内设计温度建议为23℃~24℃。 相似文献
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为了消除传统恒温恒湿空调系统中冷热抵消现象,提出了一种新型直接膨胀式温湿度独立控制恒温恒湿空调系统(下称新型空调系统).该空调系统通过组合三级直接膨胀式制冷单元、加热器、加湿器,并配备特有的控制策略,可以在满足恒温恒湿环境一定温湿度控制精度的前提下,实现温湿度解耦控制.该空调系统不会造成投资成本大幅增加,并具备结构简单... 相似文献
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There has been a rising concern in controlling the high indoor humidity of hot and humid countries. When an air-conditioned space experiences only part of its design heat load, its humidity tends to rise as a result of the air-conditioning system trying to control the indoor temperature by reducing its cooling capacity. In this study, the part-load dehumidification performances of three temperature control strategies are compared, namely, chilled water flow control, bypass air control and the variable air volume control. Coil simulations are employed to study the part-load performance of these control strategies. The coil model has been validated with experimental data to within ±6.5%. The relative humidity of a space depends of factors such as design sensible heat factor of the space, temperature control strategy employed and load condition experienced by the space. Simulation results have indicated that chilled water control strategy results in the highest indoor humidity throughout the range of conditions studied while variable air volume system provides highly effective dehumidification performance of the cooling coil. Bypass air control appears to be a good option for adoption as it is able to provide an acceptable humidity over a wide range of load conditions without having to affect the air movement within the space. 相似文献
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Many air conditioning systems have small moisture removal capacities and are not equipped to maintain space humidity under part-load conditions particularly during hot and humid periods. They are able to provide desired temperature control but humidity. The primary objective of this work is to identify control strategies that can be used to prevent significant indoor humidity degradation during part-load conditions. These control strategies are chilled water flow control, bypass air control, variable air volume control, run-around coil control and low face velocity/high coolant velocity control. Coil simulations have been employed to study the part-load performance of these control strategies. The coil model compares favourably with experimental data to within ±6.5%. Simulation examples are conducted for each control strategy under varying part-load conditions. Results from the coil model have indicated that some strategies are more effective than others in sustaining acceptable indoor humidity under part-load conditions. For instance, chilled water control strategy has been observed to produce highest indoor humidity throughout the range of conditions studied while variable air volume system provides highly effective dehumidification performance of the cooling coil. In addition, higher ventilation rates have been observed to increase the space humidity during part-load conditions. 相似文献
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以大空间缩尺模型实验室为研究对象,基于Block模型,采用2种常数法及3种温差法的表面对流传热系数取值方法,计算室内在下送中回气流组织下的空气垂直温度分布。通过与实验值的比较发现,对流传热系数温差法计算结果优于常数法。其中一种对流传热系数温差法得到的空气垂直温度与实测温度的误差最小。 相似文献
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针对变风量空调实际运行中出现的冷热不均问题,通过运行两种变静压、一种定静压控制策略下的变风量系统,对比分析室温、风量、风机频率、最大阀位、设定静压值与风机能耗的关系。结果表明:变风量箱在设计控制阀门的算法中除设定温度之外还需要考虑IAQ、相对湿度等因素;使用变风量空调之前应将室温降至设定温度后再打开自动控制系统,避免受到算法的延迟影响;定静压输送单位冷负荷需要消耗的电量,比测点靠近风机的变静压控制策略多7.8%,且降温效果较差;外界环境几乎相同的情况下,变静压策略中,静压基础点远离风机的控制策略较靠近风机的控制策略降温效果好,速度至少快14%,消耗电量几乎相同。 相似文献