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.

Numerical Analysis on Ventilating and Air Conditioning Scheme of Shenyang Subway Station

Different cities have different climate conditions and outdoor temperature and humidity, so the scheme of an environment control in subway should be analyzed by considering objective conditions, project cost and operating status. In this paper, a physical and mathematical model is built according to the design of Shenyang subway (line 1), the boundary conditions of the model are defined by the design and experiments, the numerical analysis of ventilating scheme and air conditioning scheme is introduced individually, and the temperature field and air flow field of the two schemes are compared, so that the feasibility of using a ventilating scheme in subway of northeast cities is discussed. Considering comfort and economy, it can be concluded that mechanical ventilation is feasible in subway of northeast cities because the air temperature there is not very high in summer.

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.

Building cooling by night-time ventilation

Nowadays,the world is short of energy source,and larger proportion of building energy consumption is occupied by air conditioning system. It is urgent that not only importance should be attached on energy saving but also arcology energy technology based on green and sustainable thought should be advocated. Considering the ever growing energy consumption of residential buildings,intermittent ventilation is a solution to saving energy consumption and improving indoor thermal comfort. Aiming at reducing indoor air temperature by intermittent ventilation and decrease energy consumption of air conditioning system,with the help of DeST (Designer's Simulation Toolkit) this paper analyzes the characteristics of air conditioning load and year round air conditioning time in Chongqing located in hot summer and cold winter zone,obtains the amount of energy consumption saved at different ventilation rates,and recommends suitable ventilation rate in hot summer and cold winter zone.

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.

日本HEAS-02-2022《医院设施设计指南(空调设备篇)》介绍

日本HEAS-02《医院设施设计指南(空调设备篇)》已经持续应用了30多年,对我国医院建设影响较大。历经4次修订,最新颁布的2022版是由医学主席在疫情中主持修订的,鉴于气溶胶新的传播特性提出了相应的合适措施。在医疗环境控制方面提出了许多新的思路与措施,局部修订了空气洁净度级别和各医疗科室的通风要求。依据感染管理风险评估及推荐强度与证据质量实施合理的医疗环境控制,并对一些关注点进行了澄清。

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。

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。

某有机化学实验室项目通风空调系统设计

有机化学实验往往会产生对人体有害的气体,有效的通风空调系统可以避免有害物泄漏,以保证实验人员在工作环境里的安全和健康。不同的有机化学实验室要求不同,其通风空调系统设计也有相应的不同要求。合成实验室通风量大,但对房间温湿度要求不高;分析仪器实验室中仪器设备较多,发热量较大,且对环境温湿度有一定的要求。本文结合某实际工程,对不同功能化学实验室通风量的确定、新风送风温度及空调设置情况和通风系统控制进行了介绍。

基于多平台混合教学模式在通风空调工程课程中的应用探讨

为提升通风空调工程课程教学效果,探讨了一种混合教学模式在通风空调工程课程中的应用。该模式融合翻转课堂与多平台构成。开展翻转课堂教学、建立基于互联网的“小范围”知识获取平台,以及研究生与本科生互动平台,三者融合以提升学生课程参与度,提高课程知识转化率,增强本科学生与土木水利专业学位硕士互动,完善课程教育体系。最终达到学生在通风空调工程领域的专业素养和实际应用能力逐步提高的目的,为通风空调工程课程的教学改革提供有效的经验。

核电通风空调系统故障检测与诊断

通风空调系统为核电厂系统设备的稳定安全运行和人员安全操作提供可靠的保障,实现通风空调系统的稳定运行对核电厂房的平稳运行具有重要意义。该文针对核电厂通风空调系统的典型故障进行具体介绍,并综述现有通风空调系统故障检测诊断的具体方法、特点与不足,最后深入分析核电通风空调系统故障诊断未来的研究方向。

家庭厨房内不同比例混氢天然气泄漏扩散研究

为探究不同比例混氢天然气在家庭厨房内泄漏后的扩散特性,采用FLACS构建家庭厨房数值模型,研究不同比例混氢天然气泄漏后在水平(泄漏口侧到远离泄漏口侧)和垂直方向上的浓度分布,对比自由扩散和对流通风对气体扩散的影响。研究结果表明:距泄漏口上方1.15 m高度以下,高度、时间及混氢比对水平方向上气体体积分数的降幅影响较小;泄漏口侧和远离泄漏口侧垂直方向上具有不同层级的分层现象,且随混氢比和时间的增大,分层现象减弱;混氢比从0%增加到40.0%时,报警时间降幅比仅为1.42%;相较自由扩散,对流通风能快速排出可燃气体,降低风险。研究结果可为城镇燃气混氢应用提供参考。

我国屏蔽门地铁站的通风空调合理能耗修正方法

[目的]针对地铁站能耗持续增长的态势,为准确评价当前地铁站用能水平,挖掘节能潜力,推动建筑节能工作,需要对屏蔽门地铁站的通风空调合理能耗修正。[方法]采用能耗原理模型,系统性地建立了各气候区地铁站的合理能耗基准。针对寒冷地区、夏热冬冷地区和夏热冬暖地区等不同气候区的典型城市,模拟得到了基准工况下的屏蔽门地铁站通风空调系统能耗约束值和引导值。考虑到各地气候差异和车站服务状况的差异,定量分析了气候条件、客运量、发车对数和隧道长度对地铁站通风空调合理能耗的影响程度,进而提出了各气候区不同城市、不同服务状况的屏蔽门地铁站通风空调系统合理能耗的修正计算方法。[结果及结论]气候条件中年平均湿球温度与能耗的相关性最高,相关系数R²为0.950;年总客运量从500万人次增加到1100万人次,各气候区合理能耗指标增加2.2%~2.9%,各气候区之间差异不大;日总发车对数从140对增加到310对,各气候区合理能耗指标增加了2.0%~7.4%,不同气候区之间具有明显差异;隧道长度1200m的车站比800m的车站,合理能耗指标高1.5%~4.9%,不同气候区之间具有明显差异。

对撞射流下通风空间的流场结构实验研究

为了研究送风口和回风口位置对室内流场结构的影响,本文搭建了采用多条缝对置撞击送风的通风缩比模型实验平台,利用激光粒子测速技术研究了等温和非等温工况下多条缝通风空间中不稳定气流场的速度和湍流信息。结果表明:等温和非等温工况下,送风口截面的流场速度、湍动能和涡量的空间分布类似,最大值分别可以达到1.3 m/s、0.1 m^(2)/s~2和60 s^(-1),射流碰撞形成2个大尺度涡旋,造成流场结构不稳定;CS4.5截面,流场速度、湍动能和涡量最大值分别可以达到0.9 m/s、0.04 m^(2)/s~2和30 s^(-1);CS3.5截面,速度与涡量最大值均出现在近壁面附近,分别为0.42 m/s、8 s^(-1),湍动能最大值出现在截面中间位置,为0.13 m^(2)/s~2,且流场中形成了大规模的涡旋;非等温工况下,送风口截面和CS3.5截面中小尺度涡旋增加,大尺度涡旋减少,热羽流抑制了大尺度流场结构,增加了小尺度流场结构。

机场航站楼暖通系统减振与消声技术研究及探讨

航站楼是机场的重点建筑,属于建筑容积率大、空调负荷密度高的超大型建筑。由于楼内设有商场、餐厅等服务设施,设备运行时所产生的噪声及振动会为使用者带来困扰,严重甚至会危害人们的身体健康与安全。因此基于某国际机场对设备安装时采取的消声减振设备设计进行了探讨。

定变风量阀在实验室通风空调系统的应用探讨

描述了定、变风量阀的工作原理和应用特点,基于某实验室的工程案例,根据实验室的不同使用功能要求,采用定、变风量阀实时调节实验室的送风量和排风量,且通过实验室房间的风量差独立控制室内静压。在保证实验室安全运行的情况下,定、变风量阀的合理应用可降低空调通风系统的能耗,从而可减少系统的运行费用。研究结果为优化实验室通风空调系统的设计提供理论依据和技术指导。

疫情防控形势下博物馆空调通风系统运行和管理方法探讨

博物馆空调通风系统既为文物提供适宜的展出、存储环境,也为参观人员提供舒适的热环境。面对疫情,博物馆空调通风系统如何有效避免成为病毒传播的媒介,是值得暖通专业运行管理人员分析、探讨的问题。本文结合文物保护需求和防疫工作需要,探讨了博物馆空调通风系统在新形势下的运行管理办法,为减少、控制病毒传播提供参考。

某人防中心医院战时通风空调设计

以某人防中心医院为例,给出其通风系统具体计算过程,分析人防地下室的冷热负荷特点,空调冷热源采用风冷热泵型除湿空调机,提出在设计过程中的注意事项,给出毒剂报警器探头在壁龛中安装的示意图,为今后相似的工程提供借鉴。

绿色低碳城轨通风空调节能措施探讨

城市轨道交通在优化城市功能配置、解决交通拥堵问题、提升居民出行环境等方面发挥着重要作用,但同时,作为“用能大户”城市轨道交通需要耗费大量能源。近年来,随着“碳达峰”“碳中和”目标的提出,发展绿色低碳城轨成为人们的共识。地铁通风空调系统能耗约占地铁车站运营能耗的50%~60%,其节能措施研究对提高能源利用效率及绿色低碳城轨具有重要意义。结合工程设计经验,分析了目前城市轨道交通中通风空调系统运行现状及存在的问题,结合大系统、小系统、多联机系统及空调水系统的具体节能设计方案,从设备和系统配置方面探讨了主要节能措施和节能技术发展方向。

轨道交通地下车站暖通设计方案探究及选择

文中通过轨道交通地下车站大、小系统空调通风及排烟系统形式的对比分析,结合不同车站的建筑特点和国家规范,针对不同地区及结构层高的地下车站暖通系统方案进行探讨,选取合理的暖通系统方案,在满足规范和设计要求的同时,尽量降低工程造价,减少后期车站运行费用。