相对封闭环境增氧的实验研究

本文对相对封闭环境增氧进行了实验研究。结果表明,制氧机氧气流量对相对封闭环境内氧浓度变化起着决定性作用,循环风影响室内氧浓度的扩散和分布。相对封闭环境不增氧时,室内人员耗氧导致该环境内氧浓度明显下降,增氧可以显著提高相对封闭环境内的氧含量。与传统增新风空调系统相比,相对封闭环境增氧系统可以大幅度降低能耗,节约运行成本。     

民用飞机机载分子筛制氧系统初探

本文概述了机载分子筛制氧系统的现状,提出了民用飞机机载分子筛制氧系统概念构架,并对民用飞机机载分子筛制氧系统研究方向进行了展望。     

青藏铁路客车弥散供氧条件下需氧量的计算

青藏高原高寒缺氧的气候环境要求青藏铁路客车必须具备一定的制氧补氧功能.在现有的国内列车制造水平条件下,弥散供氧作为一种整舱供氧方式,具备一定的优势.在借鉴相关领域科研成果的基础上,对此种方式下的需氧量进行了公式推导和计算,旨在为高原列车供氧方案的确定及供氧系统的设计提供必要的参考.     

摊铺机高原环境下对发动机增氧系统的改装

针对摊铺机在高原缺氧环境下,发动机缺氧导致的启动困难甚至无法正常施工的情况,对发动机设置增氧装置,有两种方案,一种是在发动机进气口加装风扇,向发动机进气口吹风,加快空气流动,增加氧气流量;另一种是使用氧气罐,利用氧气罐内高浓度的氧气和压力,给发动机提供高质量的氧气,以实现发动机增氧功能.该改装设计也同样可以使用在别的机型甚至别的设备上,在不改变设计理念和逻辑思路的前提下,根据不同设备的机械结构和电气原理,妥善改变或增加相应零部件和线路,并做好相应的机械及电器防护工作,都可以实现对发动机启动及施工过程中的增氧功能.     

硝酸盐对磷酸盐还原系统除磷效能的影响

通过改变进水硝酸盐浓度，考察了硝酸盐对缺氧和好氧两种不同氧环境下的磷酸盐还原系统除磷效能的影响。试验结果表明，硝酸盐对两种氧环境下磷酸盐还原系统的除磷效能影响显著。当进水硝酸盐浓度为105~160 mg/L时有利于缺氧条件下的磷酸盐还原。而进水硝酸盐对好氧条件下的磷酸盐还原产生显著抑制作用，并且两者存在显著的负相关（R2=0.982 7）。这种差异主要是由于两种不同氧环境下，硝酸盐对微环境构造的影响不同而造成的。同时，不同浓度的进水硝酸盐还会影响反应器内的pH值，进而影响磷酸盐还原进程。结果表明，偏碱性（pH8左右）有利于两种氧环境下的磷酸盐还原。     

高压增氧与活性无烟煤滤池联用去除高浓度氨氮

在5 000 m3/d处理规模的生产性示范工程条件下,开展了高压增氧系统提高待滤水溶解氧浓度、高压增氧系统与活性无烟煤滤池联用去除水源水中氨氮的研究。结果表明,该高压增氧系统的纯氧曝气效率基本保持在90%以上,将待滤水DO从6.3~6.6 mg/L提升至满足去除3~4 mg/L氨氮所需DO的总运行成本为0.040~0.049元/m3;当待滤水氨氮≤3.5 mg/L时,高压增氧系统与活性无烟煤滤池联用,能使滤后水中氨氮浓度降至国标限值(0.5 mg/L)以下。     

档案灭火系统注氮控氧膜分离技术的应用研究

文章分析了注氮控氧膜分离技术的供气、气体分离、氧浓度探测、恒温恒湿空调、自动控制等组织架构内容,指出了注氮控氧膜分离技术在档案消防灭火系统中的工作机理,并比较了注氮控氧灭火系统与传统档案灭火系统的区别,为做好档案消防工作提供参考。     

几种增氧方式对黑臭河湖的治理效果对比

为了解如何更好地治理黑臭河湖,本研究在对比了市面上的几种增氧机械特点后,设置多组对比试验,从水体含氧量的测定和水温的测定出发进行试验,以期对比曝气微孔增氧与机械增氧的区别。用多种不同的增氧方式对同一池塘进行测定(9—10月),获得池塘表层与底层的溶氧量、水温差等指标数据。结果表明,曝气微孔增氧技术具有更高的性价比,对于水中的溶氧量增加更有效果,同时对于时段性温差明显地区水层表层与底层的温差调节作用明显,有更强的降温效果。     

高效强热商用涡旋技术在热泵空调中的应用

本文介绍了喷气增焓技术在热泵空调中的应用。EVI通过在系统中设置经济器来获得更高的制冷（热）量,同时提高系统效率。经济器有闪蒸器和板式换热器（过冷器）两种,文中分别给予了介绍。EVI有两种应用方案,分别侧重于提高低温环境下的制热量和能源效率,通过实测证明这两种方案能够达到相应的技术目的。     

缺氧空调房间富氧特性及富氧效果的模拟研究

利用实验及CFD模拟软件分别研究非空调工况下以及空调工况的送氧口个数、送氧口管径、送氧流量及送氧方式、不同的气流组织形式(同侧上送下回、异侧上送下回)等发生变化对密闭建筑缺氧房间的富氧特性及富氧效果的影响.结果表明:非空调工况下,送氧口个数、送氧口管径、送氧流量及送氧方式不同,所形成的富氧区域差别较大,宜采用管径为6 mm的相背45°的双送氧口进行送氧,所形成的富氧面积为最大;空调工况下,送氧口个数、送氧口管径、送氧流量及气流组织形式不同,所形成的富氧区域形状大体相似,均为"椭圆"形状,宜采用送氧口管径为6 mm的单送氧口且异侧上送下回的气流组织形式;空调工况下,送氧流量相同时,送风风速为0. 85 m·s~(-1)所形成的富氧面积比送风风速为1 m·s~(-1)所形成的富氧面积大约20%;当送风风速均为0. 85 m·s~(-1),送氧流量为1. 5 m~3·h~(-1)所形成的富氧面积约为0. 96 m~2,该富氧面积与单人次活动范围面积相当,适宜作为空调工况下缺氧房间单人次的富氧基础供氧量.模拟结果可为缺氧空调房间供氧装置的选择、布置、降低新风量、降低空调能耗等方面提供参考.     

青藏铁路客车暖通空调设计问题探讨

探讨了青藏铁路客车暖通空调设计中须考虑的低气压环境对列车空调系统的影响,列车电加热器设计时的注意事项,以及新风系统与供氧系统的集成等问题。     

Enhancing nitrification in vertical flow constructed wetland utilizing a passive air pump

Nitrification of simulated secondary effluent solution using a variant of the vertical flow bed constructed wetland was studied. In this system oxygen required for the nitrification process is supplied by a passive air pump. The passive air pump is based on a fill and draw cycle, where oxygen depleted air is removed from the system while fresh air is introduced. Each volume of effluent drained is displaced by an equal volume of fresh air. Spatial and temporal oxygen distribution in the system as a function of drained effluent volume was investigated. Experimental results of nitrification and the corresponding oxygen consumption show good agreement with theoretical calculations based on physico–chemical considerations. Observations show that while oxygen distribution within the media was found to be non-uniform at the beginning of each cycle, it approached more uniform distribution with time. The latter resulted mainly from diffusion of oxygen in the gaseous phase.     

A simulation appraisal of performance of different HVAC systems in an office building

The article reports on a simulation appraisal of energy consumption, energy costs and environment impact of three systems used for space heating, and space cooling of an office building in Kragujevac, Serbia. Three investigated systems are (1) a system with a natural gas boiler and convective baseboard heaters for water space heating and window air conditioners for air space cooling; (2) a system with a natural gas boiler and individual air reheaters for air space heating and a chiller plant for air space cooling; and (3) an air-to-air heat pump for air space heating, and cooling. The systems are modeled and simulated by using EnergyPlus software. After simulations, it is found that the first investigated system has the highest energy efficiency, the best economy, and the lowest environmental impact. That is because of the fact that the first system has water as a heating medium and uses predominantly natural gas as fuel. However, in future, when for generation the grid electrical energy requires less primary energy, and becomes decarbonized, the third system would be best to conserve energy resources and environment.     

基于MATLAB的空调系统专家PID控制的建模与仿真

以一个典型的空调系统为研究对象,建立了空调房间的简化数学模型,通过MATLAB编程实现了专家PID控制系统的设计和仿真。仿真结果表明,专家PID控制在快速性、抗干扰性等方面优于常规PID控制。     

开窗渗透对于空调房间热湿环境影响分析

定量分析了空调房间开窗对室内热湿环境的影响,主要采用计算流体力学及系统仿真方法分别对建筑渗透风量及在此风量下室内的温湿度进行了分析,并以上海某高层建筑为例具体阐述了上述方法。案例分析表明对于特定建筑来说,当室外温湿度在一定的范围内时可以在保证室内舒适性的前提下利用开窗渗透进行通风换气以补偿新风,同时稀释室内污染物。     

Energy savings due to changes in design of ventilation and air flow systems

Procedures for the design of ventilation and air flow systems are shown to be energy wasteful. The cause lies both in the methodologies and their technical bases, and in the influence of other factors that enter into a final systems choice for a building (particularly economics).The issue of general outside air requirements is discussed. It is found that any system in which outside air supply is sufficient to control body odor necessarily meets oxygen requirements many times over, and that the ventilation rate can be reduced by about 45% to 60% if higher humidities are used. The long-standing belief that required ventilation flow rate for odor control must increase as air space per occupant decreases has previously been proven untrue, yet a survey of the ASHRAE recommendations and various building codes shows that present standards are based on this inaccurate and energy-wasteful principle. New standards, including a rate of 7.5 cmf/person of outdoor air (not conditioned) during the heating season, are proposed based on the result that the ventilation rate is independent of air space per person.Air distribution systems and sub-systems are analyzed in terms of minimum energy requirements. Energy saving by velocity reduction is discussed. Fan power requirements for a high velocity air distribution system are increased by 2500% over that for a low velocity system in commercial buildings.A comparison of the “old” ASHRAE definition of Effective Temperature, which serves as a thermal comfort criterion in AC systems design, is made with the “new” definition, and the consequent energy savings that should result when the “new” definition is accepted in practice is demonstrated.     

燃烧系统的能量效益分析

对目前广泛采用的各种燃烧系统,分析揭示了其能量效益与燃气终温以及系统中各设备的分效率之间的内在规律。计算结果表明,回热预热燃烧系统具有高的能量效益,氩等离子气体燃烧系统的能量效益较低。对于各种氧基燃烧系统,则以氧—浓缩空气系统的能量效益最高,用电能增加甲烷—空气气体火焰能量的系统,要比氧—浓缩空气系统的能量效益低。     

基于人工神经网络的变风量空调控制系统

研究了变风量空调系统神经网络预测优化控制方法,优化指标考虑了舒适性和耗能量,舒适性指标取PMV指标,耗能量包括风机和冷水泵能耗。系统的控制量为送风风速和冷水流量,被控参数为空调区域的温湿度,采用预测滚动优化控制算法训练多层前向神经网络,然后将其作为优化反馈控制器来求解变风量暖通空调系统的优化解,并在运行中实时预测空调区域的负荷。仿真结果表明,采用此方法,在模型环境、负荷参数变化的情况下,既可以达到节能的要求,又可以使空调区域的温湿度保持在舒适范围内。     

办公楼建筑窗际热环境的改善和节能

从办公建筑的热舒适出发，说明了改善窗际热环境的必要性，指出除通过建筑构造来改善外，空调分内外区是常用的手法，但会带来能量混合损失。介绍了一些可以不设外区空调系统而又能改善窗际热环境的空调措施。