Development of Temperature-Humidity Independent Control Air-Conditioning Unit for Residential Buildings

Cooling panels are increasingly used in domestic residential buildings.To provide medium temperature cold water for the cooling panel,and dehumidify the indoor air simultaneously,a new kind of temperature-humidity independent control air-conditioning unit was developed for single residential house by utilizing multi-variable technology.First,the supply air temperature was studied to determine the proper supply air flow rate for the humidity control.Then,the energy consumption of different temperature-humidity independent control systems was studied.The analysis indicates that unity evaporating temperature can be used to handle the moisture load and sensible heat load in two evaporators.So the unit scheme was put forward.Two evaporators were used to produce medium temperature water and dry air separately,and electric expansion valves were used to control the refrigerant distribution between the two evaporators.Then,experimental work was carried out to investigate the influence of compressor frequency,refrigerant distribution on the dehumidification capacity,energy efficiency and refrigeration capacity.In the end,the paper concludes that both compressor frequency and refrigerant distribution can control the dehumidification capacity,but the former influences the EER more than the latter,while the latter influences the refrigeration capacity more than the former.We can find a proper running point at certain sensible and latent cooling load by adjusting both compressor frequency and electric expansion valve.The energy consumption of this kind of unit was estimated and compared with present room air conditioners,which shows that it can save about 41% cooling energy consumption.

COMPUTER DECOUPLE CONTROL OF TEMPERATURE AND HUMIDITY IN PREPROCESSING CHAMBER OF AIR-CONDITIONING TEST EQUIPMENT

This paper deals with the application of decouple Control theory to temperature and humidi-ty control in air-conditioning system. The decouple control algorithm for bivariable systems isderived applicablly for air-conditioning system. The algorithm is used to design a temperatureand humidity computer control system for the preprocessing chamber of air-conditioning testequipment. The results of the real-time control experiments indicate that the decouple controlalgorithm is feasible, the control quality is improved and high control precision is achieved.

Visco-elastic-plastic model of deep underground rock affected by temperature and humidity

As the depth of exploitation increases,studies on constitutive models of rock affected by temperature and humidity become very important.Based on the Nishihara model,a visco-elastic-plastic rock model was established by using the coefficients of thermal and humidity expansion,thermal viscosity attenuation,humid viscosity attenuation and acceleration rheology components.We used the definition of a controlled heat circle to explain the model.The results show that the behavior of rock,affected by temperature and humidity,is stable as a function of time when the stress is lower than the first yield stress σS1;the creep rate will increase due to the effect of temperature and humidity when the stress is greater than or equal to σS1;the creep rate will accelerate at an increasing rate when the stress is greater than or equal to the second yield stress σS2,which results in a failure of the roadway.The model derived in this study can completely describe visco-elastic-plastic characteristics and reflects the three stages of rock creep.

Temperature and Humidity Control in Greenhouses in Desert Areas

Water consumption can be reduced by using a greenhouse for agriculture in desert areas. We analyzed the effect of control of ventilation, sprinkler water, and solar radiation?shielding on changes of temperature and humidity in a greenhouse under various desert area conditions. We calculated the changes in temperature and humidity in a greenhouse for a whole day in four seasons, and the calculation results of water consumption with and without a greenhouse were compared. When ventilation, shielding, and sprinkler water were controlled under suitable conditions to grow orchids in a desert area, water consumption in July was only 7% of that without a greenhouse.

Reliability Evaluation of Wind Power Converter Under Fault-tolerant Control Scheme with Quantification of Temperature and Humidity Effects

Wind power converter(WPC)is a key part of a wind power unit which delivers electric energy to power grid.Because of a large number of semiconductors,WPC has a high failure rate.This paper proposes a method to accurately evaluate the reliability of WPC,which is crucial for the design and maintenance of wind turbines.Firstly,the index of effective temperature(ET)is presented to quantify the effects of temperature and humidity on the semiconductor operation.A novel method is proposed to evaluate the lifetime and calculate the aging failure rates of the semiconductors considering the fluctuations of ET.Secondly,the failure mode and effect analysis(FMEA)of WPC is investigated based on the topology and control scheme.The conventional two-state reliability model of the WPC is extended to the multi-state reliability model where the partial working state under the fault-tolerant control scheme is allowed.Finally,a reliability evaluation framework is established to calculate the parameters of the WPC reliability model considering the variable failure rates and repair activities of semiconductors.Case studies are designed to verfify the proposed method using a practical wind turbine.

Room temperature and humidity decoupling control of common variable air volume air-conditioning system based on bilinear characteristics

Variable air volume(VAV)air-conditioning(AC)systems are widely employed to achieve a comfortable room thermal and humid environment depending on its better regulation performance and energy efficiency.In the single coil VAV AC system,conventional proportional-integral(PI)control algorithm is usually adopted to track the set-points of the room temperature and humidity by regulating the supply air flow rate and the chilled water flow rate,respectively.However,the control performance is usually not good due to the high coupling of the heat and mass transfer in the air-handling unit(AHU).A model-based control method is developed to realize the decoupling control of the room temperature and humidity according to the bilinear characteristics of the temperature and humidity variation.In this control method,a bilinear room temperature controller is used to track the room temperature set-point based on the real-time cooling load,while a room humidity controller is used to track the room humidity set-point depending on the real-time humidity load.The control performance was validated in a simulated VAV AC system.The test results show that comparing with the conventional PI control,the room temperature and humidity are controlled much more robustly and accurately by using the proposed model-based control method.

Thermodynamic performance assessment of vacuum membrane-based dehumidification and air carrying energy radiant air-conditioning system(VMD-ACERS)

Temperature and humidity independent control(THIC)air-conditioning system is a promising technology.In this work,a novel temperature and humidity independent control(THIC)system is proposed,namely VMD-ACERS,which integrates vacuum membrane-based dehumidification and air carrying energy radiant air-conditioning system.This work establishes a novel coefficient of performance(COP)model of VMD-ACERS.The main parameters affecting the COP of conventional fan coil unit cooling system(FCUCS)and VMD-ACERS are investigated.The performance of FCUCS and VMD-ACERS are compared,and the energy-saving potential of VMD-ACERS is proved.Results indicate that,for FCUCS,the importance ranking of parameters is basically stable.However,for VMD-ACERS,the importance ranking will be affected by FCU and refrigerant.The most important parameters of VMD-ACERS are condensation temperature and permeate side pressure.On the contrary,superheating,subcooling are relatively less important parameters.For VMD-ACERS,it is not necessary to pursue the membrane with very high selectivity,because the selectivity of membrane would also be a less important parameter when it reaches 500.The COP of VMD-ACERS is higher than that of FCUCS when the permeate side pressure is higher than 8 k Pa.The VMD-ACERS solves two technical problems about power-saving and thermal comfort of conventional THIC,and can extend the application of THIC air-conditioning system.

Optimization of hot-air microwave combined drying control system based on air outlet temperature and humidity monitoring

Microwave drying is one of the most important drying methods in agriculture.The online measurement and control of material dried,as a challenging research issue,is helping to improve the drying quality of the final product and the energy utilization efficiency of microwave dryers.In order to realize the online measurement of temperature in microwave drying,a detection strategy was based on the temperature and humidity monitoring at the air outlet of coupling hot air and microwave drying method.LabVIEW programming software was employed to collect the temperature and humidity signal value at the outlet of the dryer to estimate the drying degree of the material.According to the amount of moisture removal in real-time,the microwave input power was adjusted gradually in the microwave drying process.Taking potato as material dried,the microwave power of microwave and hot air coupling drying is monitored to realize the real-time regulation.The results showed that the total color difference value of the product of 3.09,the rehydration ratio of 2.92,the unit energy consumption of 17419.35 kJ/kg,and the drying rate of 0.442 g/s were obtained.The minimum comprehensive weighted score of the product was 26.36.Compared with the orthogonal experiment,the optimal drying process was obtained as the total color difference value of the product of 2.84,the rehydration ratio of 3.01,the unit energy consumption of 17419.35 kJ/kg,and the drying rate of 0.397 g/s.The minimum comprehensive weighted score of the product was 20.67,and the difference was not significant.The control strategy not only solves the non-uniform phenomenon of drying,and makes the microwave drying real-time and continuous,but also improves the drying efficiency and quality.

基于窄带物联网的茶叶灭虫控制系统研究

为克服当前物联网在丘陵地区农业生产过程中存在通信距离短、消耗功率大、终端数量易饱和等问题,以茶叶虫害防治为研究对象,将窄带物联网技术与农业生产相结合,实时精准监测土壤温湿度,并根据土壤温湿度数据变化远程控制茶叶灭虫电磁阀启闭状态,设计了智能茶叶灭虫控制系统,并优化了超级电容太阳能电源管理、无线传感网络监测、远程监测控制等核心技术及关键模块。试验结果表明:系统运行稳定,能通过窄带物联网技术实时监测、传输土壤温湿度信息,终端可实时远程控制茶叶灭虫电磁阀,实时启闭茶叶灭虫系统,达到了实时精准监测和远程控制的目的。研究弥补了当前物联网在农业生产中应用的不足,提高了太阳能电源使用效率,延长了蓄电池使用寿命,可为我国智慧农业发展提供参考。

基于控温控湿的沙棘红外联合热风干燥均匀性与工艺

新鲜沙棘含水率高且易腐烂变质,干燥是延长货架期的重要方式之一。针对现有沙棘热风干燥周期长、品质差、能耗高等问题,该研究基于控温控湿设计了一种红外联合热风干燥装置,并对装置的气流分配室结构进行了优化,设计了一种圆柱形扰流板和方形挡风板,利用数值模拟软件COMSOL对干燥装置中速度场、温度场和湿度场进行了模拟,结果表明通过增加半圆柱扰流板能够改变干燥层间气流量,解决干燥不均匀性问题;借助增设扰流板能够提高气流速度,利用自由流区域高温低湿干燥介质的干燥能力,防止干燥层内不同区域出现干燥不均匀的现象。优化后的干燥室结构将5个干燥层间的最大速度偏差比显著降低。以沙棘为研究对象对干燥工艺进行了试验研究。结果表明,不同干燥温度对沙棘控温控湿红外联合热风干燥时间有显著影响,干燥水分比随干燥时间的增加呈现指数下降趋势。基于层次分析法得到各干燥特性和干燥品质权重,采用综合评价方法得到不同干燥温度下75℃干燥条件综合评分最高。不同介质湿度干燥条件下,当介质湿度为10%干燥时,干燥所需能耗最低,干燥后沙棘复水比最高,具有最高的维生素C(vitamin C,Vc)保留率和总黄酮含量,综合评分最高。40%介质湿度不同持续时间下,40 min得到的沙棘亮度值、复水比、Vc保留率和总黄酮含量最高,综合评分最高。该研究明确了控温控湿沙棘红外联合热风干燥最优工艺,对提升沙棘产地初加工机械化水平,促进沙棘产业健康持续发展具有重要意义。

杭州国家版本馆恒温恒湿空调系统设计

介绍了恒温恒湿库房空调系统的设计,提出了可在库房建成初期、运行稳定期、战时等灵活切换的3种运行模式,分析了其各自的处理过程与节能性;给出了平、战时空调系统选择方案,提出了平时回收空气源热泵机组和冷水机组的冷凝热作为再热热源,战时利用新风预冷实现温湿度独立控制的方法;利用CFD模拟对室内气流组织进行了优化设计;提出了采用含湿量控制代替定露点法进行湿度控制和风机变频等控制策略。通过调试与运行,证明了各项设计措施在项目中应用的有效性。

黄茶自动化闷黄装备设计与温湿度控制方法研究

闷黄是黄茶加工中的特有工艺,目前黄茶加工中缺乏专用的连续化、自动化闷黄加工装备。为此,本文设计一种用于黄茶闷黄的专用装备。根据连续化加工需求,设计了闷黄装备的机械结构,核算了装备所需的加热功率和蒸汽流量,并完成了相关部件的选型和样机构建,提出了一种基于区间二型模糊理论的温湿度控制算法。温湿度控制系统试验结果表明,在不同试验条件下,区间二型模糊控制算法能够精准控制温湿度参数,对比一型模糊控制算法,对扰动的抑制能力更强,控制误差更小。生产试验结果表明,温度和相对湿度的均方根误差最大值分别为0.439 1℃和1.226 2%,产品的感官评审结果表明,采用该装备加工的产品符合皖西黄茶的品质要求。

基于PLC控制的流体温湿度自动控制系统研究

针对某性能分析试验台架传统的手动操作进行了自动化改造,阐述了改造的整体思路,给出了硬件结构的系统结构图及软件设计流程;基于PLC控制与主机通信自动调整试验参数与自动采集存储试验数据;引入云端服务器,将数据实时传入云端,实现对试验台架的远程控制及远程数据读取保存。结果表明,经改造后的性能分析试验台架在自动模式下实现了全自动调节温湿度参数直至试验达到稳定状态,且在手动模式下,可调节本地与远程两端的试验参数,极大地提高了系统的稳定性。在两种模式下,该系统可大大降低劳动强度,减少工作量,缩短工作时间,提高工作效率。

基于Profibus的粮仓温湿度测控系统设计

实现粮仓的温湿度控制是保证粮食存储安全的重要措施之一。结合工程实际,设计了基于Profibus现场总线的全数字化粮仓温湿度测量及控制系统,以WinAC作为现场总线主站、S7-200 PLC作为从站,构成Profibus-DP现场总线通信系统。用WinCC设计出粮情测控软件,实现了粮库粮情监测和控制的各个功能要求。

温湿度冷链监控管理系统在医院药品质控管理中的应用

通过安装温湿度冷链监控管理系统,监测冷链药品温湿度。比较2022年9月—2023年2月医院药品库房和冰箱系统监测记录的温湿度与人工记录温湿度温度超标和预警情况,总结影响存储药品库房和冰箱温湿度超标的原因,提出相应的解决办法,大大降低了药品质量问题的风险。为相关部门进行冷链药品储存条件检查时提供了可靠的数据和图像。所以,温湿度冷链监控管理系统为冷链药品的储存条件提供了更可靠、有效、高效的保障,更有利于保障冷链药品的安全有效,逐步实现医院冷链药品/试剂在冷链环节全程的信息化、智能化监控管理提供参考。

温湿度检验检测技术在医疗设备质量控制中的应用研究

针对温湿度检验检测技术在医疗设备质量控制中的应用进行了研究。首先,通过对医疗设备质量控制的重要性和挑战进行分析,以及对温湿度如何影响医疗设备质量进行探讨,引出了温湿度检验检测技术在医疗设备质量控制中的应用价值。其次,对温湿度检验检测技术的原理、方法、仪器和设备进行了阐述,并详细探究了其在医疗设备性能评估、制造过程、运输和存储等方面的应用。最后,对当前温湿度检验检测技术存在的问题进行了分析,并提出了改进方法和措施。

某住宅小区温湿度独立控制空调系统设计

以南京某住宅项目为例,介绍了该项目复合式地源热泵系统、空调水系统、新风系统、空调末端、温湿度及防结露控制。该空调系统采用集中冷热源、分户换热系统,节省了管网投资,降低了输送能耗。用户侧定压补水采用竖向分区减压补水,控制用户侧毛细管系统工作压力,提高了毛细管辐射末端可靠性及使用寿命。置换新风系统采用局部微降板埋地处理,以节省户内空间。其竖向分区的新风系统减小了户内风井面积,增加了使用面积,由双冷源深度热回收新风机组集中回收排风能量,优化了冷凝器配置,热泵回收低温排风能量,提高了内置热泵效率。该项目系统设计对住宅毛细管辐射系统设计具有一定的参考价值。

基于强化学习的室内温湿度联合控制方法研究

为解决目前风机盘管控制方法仅以室内温度作为单一控制对象且忽略湿度的问题,以采用风机盘管加新风系统的北京某办公建筑为研究对象,提出一种基于动作干预的强化学习控制方法对风机盘管的送风量进行调节,以期获得更佳的室内温度和相对湿度联合控制满足率。利用TensorFlow部署强化学习算法,在TRNSYS中建立建筑空调系统仿真模型,利用自开发的TRNSYS-Python联合仿真平台对所提算法进行训练、测试和评估。结果表明:与传统的通断控制和基于规则的控制方法相比,本研究提出的控制方法可以将室内温度和相对湿度联合控制满足率提高9.5%以上。可见该方法具有工程应用价值,为提高建筑室内热舒适提供了新的研究思路。

多联机在超高标准接待项目中的应用

阐述了某超高标准接待项目暖通空调系统的设计特点,从分析落实业主对该项目的主要设计要求入手,介绍了室内设计参数优化、冷热源方案、系统划分、计算与验算、振动噪声控制、备用性及其他细部设计;重点介绍了三管制热回收高显热多联机+直膨式恒温恒湿新风机组+地暖方案在该项目中的应用,为超高标准接待项目及温湿度独立控制空调系统的设计提供了新的解决思路和案例。

模块化智能变电站精准送风系统能效管理优化策略

针对现有模块化智能变电站中智能控制柜内部环境控制不均衡、存在局部温度超出设备安全运行范围且较少考虑能效的问题,提出一种模块化智能变电站精准送风系统能效管理优化策略。首先建立空调系统热交换和管道系统空气流量数学模型,在此基础上以控制系统运行能耗最低为目标函数,提出了精准送风系统能效管理优化方法。采用高效的求解器CPLEX求解,得到能耗最低的控制策略。并通过ANSYS Icepak进行稳态过程分析,验证了系统运行的稳定性。结果表明所提方法能够实现对智能控制柜内部环境的精准控制,达到了系统绿色低碳运行的目的。