Operating Parameters of the District Heating Substation Cooperating With the Installation of Technological Air Conditioning With High Efficiency of Heat Recovery

The article analyses the problem of determining the operating parameters of the district heating substation cooperating with the air heating system in technological air conditioning systems equipped with heat exchangers with high efficiency of heat recovery.Attention was paid to the correct selection of heat exchangers for the heat output balance depending on the heat recovery protection algorithms against a drop in the temperature of the heat transfer surface below 0℃.Critical parameters were determined in Polish climatic conditions,at which the operation of the heat recovery exchanger in the air conditioning system is switched off or limited.It has been proven that the proper functioning of the district heating substation cooperating with the installation of air conditioning with high heat recovery efficiency requires the use of two heat exchangers with different characteristics,equipped with properly selected temperature control systems.The optimal model of cooperation between the technological air conditioning system and the heating substation was also indicated.

Optimal Scheduling of Residential Heating, Ventilation and Air Conditioning Based on Deep Reinforcement Learning

Residential heating, ventilation and air conditioning(HVAC) provides important demand response resources for the new power system with high proportion of renewable energy. Residential HAVC scheduling strategies that adapt to realtime electricity price signals formulated by demand response program and ambient temperature can significantly reduce electricity costs while ensuring occupants' comfort. However, since the pricing process and weather conditions are affected by many factors, conventional model-based method is difficult to meet the scheduling requirements in complex environments. To solve this problem, we propose an adaptive optimal scheduling strategy for residential HVAC based on deep reinforcement learning(DRL) method. The scheduling problem can be regarded as a Markov decision process(MDP). The proposed method can adaptively learn the state transition probability to make economical decision under the tolerance violations. Specifically, the residential thermal parameters obtained by the leastsquares parameter estimation(LSPE) can provide a basis for the state transition probability of MDP. Daily simulations are verified under the electricity prices and temperature data sets, and numerous experimental results demonstrate the effectiveness of the proposed method.

海洋平台HVAC系统减噪技术研究

文章结合海洋平台供热通风与空气调节(HVAC)系统噪声控制的现状,重点介绍了平台HVAC系统噪声对人员和设备的影响;分析了HVAC系统噪声的来源,包括机组本身运行时产生的噪声、管线内流体流动噪声等;提出了设计和安装阶段HVAC系统噪声控制的要点,如选择低噪声设备、合理布置管线、采用隔振器和消声器等。

Closed-loop bulk air conditioning: A renewable energy-based system for deep mines in arctic regions

With depletion of shallow deposits,the number of underground mines expected to reach more than 3 km depth during their lifetime is growing.Although surface cooling plants are mostly effective in mine airconditioning,usually secondary cooling units are needed below 2 kmdepth.This need emerges due to the elevated thermal impacts caused by auto-compression of mine air as well as heat emissions from strata and mine machinery.As a result,in cold climates,like Canada,ultra-deep mines need their secondary underground cooling plants running year-round while the intake air must be heated to protect the sensitive machinery and liners from freezing during the winter season.To cool mine air,horizontal bulk-airconditioners with direct spray cooling systems are commonly used due to their high performance.Conventionally,sprayed water in bulk-air-coolers are mechanically circulated and refrigerated in coupled refrigeration plants.This set up can be transformed to a natural cooling/heating process by resurfacing the warm underground bulk-air-cooler spray water for mine air heating on the surface and re-sinking the chilled water for cooling in the underground bulk air coolers.This could significantly cut-down the fossil-fuel consumption in burners for mine air pre-conditioning and refrigeration cost when applicable.This paper presents an anonymous real-life example to study the feasibility of the proposed idea for an ultra-deep Canadian mine.

Practice and analysis of recycling non-drinking water from air-condition and reverse-osmosis system into rainwater collection system

This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilization, and precipitation adjustment.The rainwater collection system in this program also adds the condensation water from the heating, ventilation and air conditioning （ HVAC） system and the concentration from the reverse-osmosis system used for watering greens and supplying waterscapes.By calculating, the quantity of the HVAC condensation water in summer is 3.48 m3/d, and the quantity of the reverse-osmosis concentrated water is 198 to 396 L/d.This method solves the water shortage caused by high evaporation in summer and low precipitation in winter.Supported by empirical monitoring data, the proposed method significantly increases the economic efficiency of the system during the summer period.

A concept of capillary active,dynamic insulation integrated with heating,cooling and ventilation,air conditioning system

When a historic façade needs to be preserved or when the seismic considerations favor use of a concrete wall system and fire considerations limit exterior thermal insulation,one needs to use interior thermal insulation systems.Interior thermal insulation systems are less effective than the exterior systems and will not reduce the effect of thermal bridges.Yet they may be successfully used and,in many instances,are recommended as a complement to the exterior insulation.This paper presents one of these cases.It is focused on the most successful applications of capillary active,dynamic interior thermal insulation.This happens when such insulation is integrated with heating,cooling and ventilation,air conditioning(HVAC)system.Starting with a pioneering work of the Technical University in Dresden in development of capillary active interior insulations,we propose a next generation,namely,a bio-fiber thermal insulation.When completing the review,this paper proposes a concept of a joint research project to be undertaken by partners from the US(where improvement of indoor climate in exposed coastal areas is needed),China(indoor climate in non-air conditioned concrete buildings is an issue),and Germany(where the bio-fiber technology has been developed).

Alternative ventilation strategies in U.S.offices:Comprehensive assessment and sensitivity analysis of energy saving potential

Mature technologies exist to reduce the heating,ventilation,and air-conditioning(HVAC) energy associated with ventilation and use ventilation proactively to save energy.This study investigated the energy use impacts in U.S.office buildings of multiple alternative ventilation strategies that combined:economizing,demand controlled ventilation(DCV),supply air temperature reset(SR),and/or a doubled ventilation rate.We used energy simulations in a Monte Carlo analysis,sampling 17 building inputs and varying locations to match the climate zone distribution of the U.S.office stock.Results indicated the possibility for significant savings compared to a baseline that ventilated constantly at a minimum rate in both a small office type with a constant air volume(CAV) HVAC system and a medium office type with a variable air volume(VAV) system.In 95%of instances,HVAC source energy savings were 5-25%in the small-CAV office(median:11%) and 6-42%in the medium-VAV office(median:27%).In the small-CAV office,DCV typically saved the most energy,usually from heating,and heating degree days and occupant density were decisive influences.In the medium-VAV office,economizing and SR were most important,DCV usually only had minor impacts,and zone temperature setpoints,along with climate indicators,were the critical influences.Other than infiltration,envelope characteristics did not strongly influence energy impacts.The untapped primary energy savings of alternative ventilation strategies over the 74%of U.S.office floorspace reasonably represented by our modeling was estimated at 36 TWh per year,with an annual value of U.S.$ 1.25 billion.

Characteristic studies of heat sources and performance analysis of free-cooling assisted air conditioning and ventilation systems for working faces of mineral mines

High temperature heat hazard at mineral mine becomes more and more serious as the increase of mining depth.Heat sources at working faces of mineral mines are complex and are of different characteristics,presenting new challenges for air conditioning systems.In this paper,heat sources at four types of working faces are summarized and their characteristics are investigated.Based on this,simplified equations,which are linear with length of working faces,are proposed to calculate heat dissipation rates.So that the main heat sources of different working faces can be found,and cooling load of air conditioning systems can be calculated.Then,considering main heat sources of coal mines,a typical working face is designed to investigate performances of different ventilation systems and air conditioning systems.Simulation results show that segmented ventilation systems(SC)and heat shield assisted centralized ventilation systems(CCHS)can realize much better temperature distributions at working faces.However,cooling load can be greatly reduced for CCHS,when untreated air is supplied to the coal seam side.Based on this,free cooling assisted air conditioning systems are designed,and annual average energy efficiency ratio(EERann)of the systems are investigated and compared between direct evaporate cooling and indirect evaporate cooling(IEC).For SC,as compared with scenarios without free-cooling,IEC can increase EERann by 15%-23%and 22%-32%under Benxi and Datong ambient conditions,respectively.Besides,to ensure high EERann,CCHS is preferred and it is essential to increase thermal insulation of air ducts.

Window Air Conditioners Transition and Restriction in Saudi Arabia

This paper will provide a proposed solution for saving energy consumption due to residential air conditioners by reducing the window air conditioners type which is the most consumed energy and has a big percent of spreading inside KSA than the split type, also it will discuss some restrictions for trading and manufacturing of air conditioner devices inside KSA besides some restrictions on market and buildings to achieve the objective of reducing the consumption of energy which become a big trend in kingdom vision 2030. The results of this suggesting solution will help the decision-makers to start its plan for execution as it has a big difference between using window type from 2022 till 2030 and if we stop its sales and replace by an efficient one of split AC type in energy consumption in addition to CO2 emission reduction and decreasing of energy cost, hence our kingdom can save petroleum raw materials and keeping the environment to become clean from pollutants so that these resources are delivered to successive generations correct and clean as we received them from those before us.

暖通空调给排水管道的表面改性与性能研究

为提升暖通空调铜合金排水管的表面性能,采用化学镀的方法在铜合金排水管表面制备了Ni-P/TiN镀层,研究镀液中TiN质量浓度对化学镀层物相组成、表面及截面形貌、硬度和耐磨性能的影响。结果表明,无镀层的铜合金基体主要物相为CuZn和CuZn5,表面镀层主要由非晶Ni组成;在基础镀液中适当添加TiN会形成镀层质量较好的含有胞状颗粒的镀层,而过量的TiN添加会使得镀层质量恶化。相较铜合金基体,表面镀层的硬度明显更高,且表面镀层硬度会随着镀液中TiN质量浓度的增加而增大;当TiN质量浓度为10 g/L时,表面镀层的硬度和磨损率分别为633 HV0.1和0.93×10^(-8)g/(r·N),具有相对较好的耐磨性,此时的磨损机制主要为氧化磨损。

基于HVAC类负荷的电力系统动态调频控制策略

以HVAC(暖通空调)类负荷为控制对象,提出了一种基于HVAC类负荷的电力系统动态调频控制策略。首先给出了HVAC负荷的等值热力学参数模型,分析了此类负荷的负荷特性;进而通过用户参与度建立HVAC负荷的温度设定值与系统频率波动之间的数学关系,给出了一种基于HVAC类负荷的电力系统动态调频控制策略,通过动态调整开关状态改变负荷功率,达到系统频率控制的目的。最后利用典型的单机电力系统模型验证了控制策略的有效性。

基于多层ReLU网络的楼宇暖通空调系统能量管理策略

提升现代智能楼宇的能量管理能力,是电力紧平衡背景下促进电网节能增效的重要举措。文中提出一种数据驱动的楼宇暖通空调系统节能控制策略,避免了传统模型预测控制对精确热力学建模的依赖。首先,在搭建楼宇热网络仿真模型的基础上,采用延时嵌入法构造输入特征,建立基于修正线性单元的多层神经网络模型,实现室内温度时间序列的多步预测。然后,针对电网的分时电价,构建滚动时域优化模型,并将其重构为混合整数线性规划的形式,实现有限控制周期内优化模型的高效求解。最后,基于Simscape搭建楼宇热仿真模型,验证了所提控制策略的有效性。仿真结果表明,所提策略能够满足温度舒适度要求,并提高楼宇的经济运行水平。

基于PSO算法的HVAC系统LSSVM预测控制

针对暖通空调(HVAC)系统,提出一种基于粒子群优化(PSO)算法和最小二乘支持向量机(LSSVM)的预测控制方法。该方法利用LSSVM建立HVAC系统预测模型并预测系统的输出值,引入输出反馈和偏差校正以克服模型失配等因素引起的预测误差,以此构造加权预测控制性能指标。由PSO算法滚动优化得到系统的最优控制量。利用该控制方法对一个HVAC系统进行仿真实验,结果表明该方法具有较好的控制效果。

溶液调湿空调在医药厂房工程应用的碳减排潜力分析

众多医药生产车间要求低湿环境,需要送风含湿在7 g/kg甚至5 g/kg以下,常规7℃冷冻水驱动的冷冻除湿方式难以完成上述除湿任务,因而医药厂房通常采用转轮除湿系统对空气进行湿处理以满足环境热湿控制需求。然而,转轮系统所需再生温度较高,通常使用高温蒸汽或电加热器作为再生热源,限制了系统的低碳化运行。溶液空调系统具有利用低品位冷热源的优势,但现有研究对于溶液空调技术在医药建筑中应用可行性研究尚不充分,无法揭示其在医药建筑应用的节能减排潜力。因此,现场测试了溶液空调系统在某试点医药厂房的实际应用效果,对比了其与常规转轮系统的性能差异并阐明差异原因。示范工程应用结果表明,一次回风系统送风含湿量在6 g/kg左右时,溶液系统可以将再生热源温度从100℃以上降至50℃以下,相较于常规转轮系统的节能比率为15%~45%,典型工况下的碳减排率为20.7%。以期为医药建筑低碳化发展提供经验参考与数据支撑。

基于HVACSIM+和MATLAB的空调系统仿真研究

研究了空调系统的仿真及一定温度要求下的最小能耗优化控制。介绍了大型空调系统仿真软件HVACSIM+;以某大厦一层中央空调系统的空气处理系统以及空调房间为仿真对象,进行HVACSIM+系统仿真;建立了表冷器的能耗与冷冻水流速之间的函数关系,将此作为目标函数,在MATLAB环境下,应用改进的变量轮换法优化控制器参数,经HVACSIM+再次仿真运行,计算冷源向空调系统提供的能耗。仿真结果表明,优化参数下的仿真系统运行稳定,与优化前相比,经表冷器消耗的能量大大减少。

协同考虑空气质量与热舒适度的暖通空调系统双层优化控制策略

暖通空调(HVAC)系统作为智能楼宇的耗能主体,实现其能耗成本与用户舒适度的灵活权衡具有重要意义。然而,并行考虑以上两种因素时,系统优化模型的耦合项增加,求解难度增大。基于学习的控制策略在模型构建上具有便捷性,但节能效果一般。面对以上挑战,提出协同考虑空气质量与热舒适度的HVAC系统双层优化控制策略。首先,基于RC等效电路的热动态模型和楼宇内部物理结构,精确刻画各区域温度和空气质量的耦合关系;然后,以能耗成本最低及用户舒适度最优为目标,对HVAC系统的运行策略进行优化,为解决模型的耦合问题,对HVAC系统进行双层优化控制,上层优化送风质量流量,下层优化通风率,并采用滚动优化方法修正误差;最后,在夏季制冷场景下,对不同舒适度系数下的双层优化控制结果进行分析,并与其他控制策略进行比较。结果表明,所提方法能兼顾经济性和用户舒适度。

探究供热通风与空调工程的施工技术要点与节能控制措施

在当代,低能耗、低污染及低排放是建筑工程施工的必然要求,同时也对其性能提出了更高的要求,如对环境友好、绿色和高效。暖通工程在绿色建筑中的运用是非常关键的一步,只有适时地转变高强度、高环境污染的施工方式,重视空调工程品质的提高,才能取得较好的节能和环境保护成效,促进企业的环保和节能。同时,在通风空调装置的安装过程中,要提高对有关施工的掌控程度,按照施工技术应用要求和通风空调装置的结构进行工程施工,确保建筑通风空调工程质量的提升。供热通风和空调工程施工水平已成为衡量施工部门资质的有效依据,为满足现阶段行业发展需求,施工团队需要进一步规范施工,严格依照建筑物施工方案与安装标准,严格制定现场施工管理策略,提升施工人员技术水平,确保各施工环节的科学性、合理性。

节能环保技术在暖通空调系统的应用研究

针对暖通空调(HVAC)系统高耗能、高污染的问题,从数据分析方面设计了HVAC系统的智慧数据中心。通过传感器获取HVAC终端的数据,利用联邦学习平均算法实现数据分析。采用多路径通信保证数据传输的安全,实现了HVAC系统精准节能运行。设计了地源热泵功能模块和热能回收功能模块。地源热泵功能模块可实现对太阳能和地热能等可再生能源的利用,保证了HVAC系统的环保性。由试验仿真的分析与对比结果可知,该HVAC系统实现了耗电量和排出热量的减少。该HVAC系统可确保节能环保技术的应用效能。

某肿瘤医院质子治疗中心空调通风系统设计

质子治疗使用质子束,其射线粒子质量很大,能对肿瘤区域进行“立体定向爆破”,对病灶区进行精准定位治疗,将身体其他部位功能细胞损伤降到最低,治疗效果良好,我国已越来越重视质子治疗中心的建设。介绍了某肿瘤医院质子治疗中心空调、通风、工艺冷却水系统的设计要点,根据设备工艺需求,提出了冷热源选取需注意的事项及节能措施,为该类医疗建筑的设计提供了借鉴。

基于PMV的多区域暖通空调事件触发间歇控制研究

提高建筑能源管理效率一直是研究的热点问题,尤其是暖通空调(HVAC)作为主要的能源消耗者.本研究针对多区域HVAC系统,提出了一种基于预测平均感觉值(PMV)的事件触发间歇控制策略,旨在提升建筑的能源管理效率及室内热舒适度.将PMV指数范围作为事件触发间歇控制的规则,设计了相应的间歇控制器,可以得到多区域HVAC系统室内温度维持在可接受范围内的可行条件,同时排除了Zeno行为;通过数值仿真与连续控制策略的对比分析,证实了该控制策略在提供良好热舒适性的同时,具有显著的节能优势.