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大气污染 3

“一带一路” 2

仿真 2

低温SOFC 2

动力气垫 2

发展 2

地效翼船 2

大气温度 2

干旱 2

数值模拟 2

温度 2

温度分布 2

温度控制 2

火灾 2

章动 2

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“Partial pressures” of humid air in wide pressure and temperature ranges

Zidong WANG, Hanping CHEN, Shilie WENG

《能源前沿(英文)》 2013年 第7卷 第4期   页码 511-517 doi: 10.1007/s11708-013-0281-7

摘要: “Partial pressure” in humid air is a question very much concerned by scientists and no satisfactory answer has been found to date. This paper proposes a novel method to obtain the “partial pressures” of the water vapor and dry air in humid air. The results obtained by the proposed method are quite different from that obtained by Dalton’s partial pressure law. The fundamental behaviors of water vapor and dry air are studied in depth in wide pressure and temperature ranges. Semi-permeable membrane models are proposed and applied for both saturated and unsaturated humid air. “Improvement factors” are developed to quantitatively describe the magnitude of the interaction between dissimilar molecules. One discovery is that the “partial pressure” of the water vapor in saturated humid air equals , rather than ( · ) which was formerly believed. The other is that the interaction between dissimilar molecules may be omitted when temperature is above “cutting-off temperature” for unsaturated humid air. This paper satisfactorily answers the quest of “partial pressures” in humid air from a new perspective.

关键词: partial pressure     Dalton’s partial pressure law     humid air     saturated     unsaturated    

Improvement of part-load performance of gas turbine by adjusting compressor inlet air temperature and

《能源前沿(英文)》 2022年 第16卷 第6期   页码 1000-1016 doi: 10.1007/s11708-021-0746-z

摘要: A novel adjusting method for improving gas turbine (GT) efficiency and surge margin (SM) under part-load conditions is proposed. This method adopts the inlet air heating technology, which uses the waste heat of low-grade heat source and the inlet guide vane (IGV) opening adjustment. Moreover, the regulation rules of the compressor inlet air temperature and the IGV opening are studied comprehensively to optimize GT performance. A model and calculation method for an equilibrium running line is adopted based on the characteristic curves of the compressor and turbine. The equilibrium running lines calculated through the calculation method involve three part-load conditions and three IGV openings with different inlet air temperatures. The results show that there is an optimal matching relationship between IGV opening and inlet air temperature. For the best GT performance of a given load, the IGV could be adjusted according to inlet air temperature. In addition, inlet air heating has a considerable potential for the improvement of part-load performance of GT due to the increase in compressor efficiency, combustion efficiency, and turbine efficiency as well as turbine inlet temperature, when inlet air temperature is lower than the optimal value with different IGV openings. Further, when the IGV is in a full opening state and an optimal inlet air temperature is achieved by using the inlet air heating technology, GT efficiency and SM can be obviously higher than other IGV openings. The IGV can be left unadjusted, even when the load is as low as 50%. These findings indicate that inlet air heating has a great potential to replace the IGV to regulate load because GT efficiency and SM can be remarkably improved, which is different from the traditional viewpoints.

关键词: inlet air temperature     inlet guide vane (IGV) opening     part-load     equilibrium running line     gas turbine (GT) efficiency     surge margin (SM)    

Experimental and kinetic study on laminar flame speeds of ammonia/syngas/air at a high temperature and

《能源前沿(英文)》 2022年 第16卷 第2期   页码 263-276 doi: 10.1007/s11708-021-0791-7

摘要: The laminar flame speeds of ammonia mixed with syngas at a high pressure, temperature, and different syngas ratios were measured. The data obtained were fitted at different pressures, temperatures, syngas ratios, and equivalence ratios. Four kinetic models (the Glarborg model, Shrestha model, Mei model, and Han model) were compared and validated with experimental data. Pathway, sensitivity and radical pool analysis are conducted to find out the deep kinetic insight on ammonia oxidation and NO formation. The pathway analysis shows that H abstraction reactions and NHi combination reactions play important roles in ammonia oxidation. NO formation is closely related to H, OH, the O radical produced, and formation reactions. NO is mainly formed from reaction, HNO+ H= NO+ H2. Furthermore, both ammonia oxidation and NO formation are sensitive to small radical reactions and ammonia related reactions.

关键词: ammonia mixed with syngas     laminar flame speed     kinetic model     sensitivity analysis     pathway analysis    

空调客车内温度控制系统仿真研究

于梅春,张登春

《中国工程科学》 2006年 第8卷 第7期   页码 83-88

摘要:

分别采用模糊控制方法与常规PID控制方法,对空调客车内温度控制系统进行了仿真研究。仿真结果表明,PID控制能消除稳态误差,但超调大,过渡时间长,在工况变化较小的情况下,能满足一定的控温要求;对于对象延迟、工况变化较大的场合,模糊控制能实时跟踪空调工况变化,较快地达到控温目标值,节能率高,综合控制效果比PID要好。

关键词: 空调客车     温度控制     模糊控制     仿真    

Effect of extrusion temperature on the physical properties of high-silicon aluminum alloy

YANG Fuliang, GAN Weiping, CHEN Zhaoke

《机械工程前沿(英文)》 2007年 第2卷 第1期   页码 120-124 doi: 10.1007/s11465-007-0021-y

摘要: Light-weight high-silicon aluminum alloys are used for electronic packaging in the aviation and space-flight industry. Al-30Si and Al-40Si are fabricated with air-atomization and vacuum-canning hot-extrusion process. The density, thermal conductivity, hermeticity and thermal expansion coefficients of the material are measured, and the relationship between extrusion temperature and properties is obtained. Experimental results show that the density of high-silicon aluminum alloys prepared with this method is as high as 99.64% of the theory density, and increases with elevating extrusion temperature. At the same time, thermal conductivity varies between 104-140 W/(m " K); with the extrusion temperature, thermal expansion coefficient also increases but within 13?10 (at 100?C) and hermeticity of the material is high to 10 order of magnitude.

关键词: coefficient     hermeticity     temperature     relationship     air-atomization    

An indirect evaporative chiller

Xiaoyun XIE, Yi JIANG,

《能源前沿(英文)》 2010年 第4卷 第1期   页码 66-76 doi: 10.1007/s11708-010-0021-1

摘要: A novel indirect evaporative chiller driven by outdoor dry air to produce cold water as the cooling source for air conditioning systems is introduced, and the principle and the structure of the chiller is presented. The cold water can be produced almost reversibly under ideal working conditions, with its temperature infinitely close to the dew point temperature of the inlet air. The key components of the chiller are an air cooler and a padding tower. To improve the heat transfer performance inside the chiller, a quasi-countercurrent air cooler was designed; a subsection linear method was used for the mathematical model of the padding tower. The first indirect evaporative chiller, designed and developed in 2005, has been in use in Kairui Building, a big hotel in Shihezi, Xinjiang Autonomous Region. The tested temperature of the water produced is below the wet bulb temperature of outdoor air and reached the average value of the dew point temperature and the wet bulb temperature of outdoor air. As the running components are only pumps and fans, the COP (cooling energy for room divided by power cost) of this chiller is high, and the drier the outdoor air, the higher COP the chiller obtained. Since no CFCs are used in this chiller, it would not cause any pollution to the aerosphere. Finally, the application prospect of the indirect evaporative chiller in the world is presented.

关键词: indirect evaporative chiller     dry air     dew point temperature    

Industrial-scale investigations on effects of tertiary-air declination angle on combustion and steamtemperature characteristics in a 350-MW supercritical down-fired boiler

Xiaoguang LI, Lingyan ZENG, Hongye LIU, Yao LI, Yifu LI, Yunlong ZHAO, Bo JIAO, Minhang SONG, Shaofeng ZHANG, Zhichao CHEN, Zhengqi LI

《能源前沿(英文)》 2021年 第15卷 第1期   页码 132-142 doi: 10.1007/s11708-020-0803-z

摘要: Industrial-scale experiments were conducted to study the effects of tertiary air declination angle (TDA) on the coal combustion and steam temperature characteristics in the first 350-MW supercritical down-fired boiler in China with the multiple-injection and multiple-staging combustion (MIMSC) technology at medium and high loads. The experimental results indicated that as the TDA increased from 0° to 15°, the overall gas temperature in the lower furnace rose and the symmetry of temperature field was enhanced. The ignition distance of the fuel-rich coal/air flow decreased. In near-burner region, the concentration of O decreased while the concentrations of CO and NO increased. The concentration of NO decreased in near-tertiary-air region. The carbon in fly ash decreased significantly from 8.40% to 6.45% at a load of 260 MW. At a TDA of 15°, the ignition distances were the shortest (2.07 m and 1.73 m) at a load of 210 MW and 260 MW, respectively. The main and reheat steam temperatures were the highest (557.2°C and 559.4°C at a load of 210 MW, 558.4°C and 560.3°C at a load of 260 MW). The carbon in fly ash was the lowest (4.83%) at a load of 210 MW. On changing the TDA from 15° to 25°, the flame kernel was found to move downward and the main and reheat steam temperatures dropped obviously. The change of TDA has little effect on NO emissions(660–681 mg/m at 6% O ). In comprehensive consideration of the pulverized coal combustion characteristics and the unit economic performance, an optimal TDA of 15° is recommended.

关键词: supercritical down-fired boiler     industrial-scale experiment     tertiary air declination angle     coal combustion     steam temperature    

综合空气污染和非适宜温度相关死亡风险构建空气健康指数 Article

张庆丽, 陈仁杰, 印冠锦, 杜喜浩, 孟夏, 邱杨, 阚海东, 周脉耕

《工程(英文)》 2022年 第14卷 第7期   页码 156-162 doi: 10.1016/j.eng.2021.05.006

摘要: 本文试图通过整合我国大气污染和非适宜温度相关的每日死亡风险,建立一种新的空气健康指数(Air Health Index, AHI)。

关键词: 大气污染     温度     空气健康指数     死亡     时间序列     风险交流    

Field measurements on microclimate in residential community in Guangzhou, China

Zhuolun CHEN, Lihua ZHAO, Qinglin MENG, Changshan WANG, Yongchao ZHAI, Fei WANG,

《结构与土木工程前沿(英文)》 2009年 第3卷 第4期   页码 462-468 doi: 10.1007/s11709-009-0066-6

摘要: Taking a certain housing in Guangzhou as an example, we conduct the field measurement of the microclimate at fixed points for air temperature, relative humidity, black globe temperature and wind speed, etc. We investigate the effects of manmade lake, shade of trees and ground surface character on outdoor thermal environment, and make a quantitative analysis on the weighting position of the landscape design factors in design behavior. The study intends to explore a method to improve the thermal environment of residential quarters by changing the corresponding factors.

关键词: microclimate     outdoor thermal environment     air temperature     black globe temperature     wind speed    

An optimized solar-air degree-day method to evaluate energy demand for poultry buildings in different

Yang WANG, Baoming LI

《农业科学与工程前沿(英文)》 2020年 第7卷 第4期   页码 478-489 doi: 10.15302/J-FASE-2019289

摘要:

The degree-day method is widely used to determine energy consumption but cannot be directly applied to poultry buildings without improvements in its accuracy. This study was designed to optimize the degree-day calculation and proposes a solar-air degree-day method, which can be used to calculate the cooling and heating degree-days and the annual cooling and heating loads under different climate conditions for poultry buildings. In this paper, the solar-air degree-day method was proposed, which considers the effects of solar radiation with different wall orientations and surface colors. Five Chinese cities, Harbin, Beijing, Chongqing, Kunming and Guangzhou, were selected to represent different climate zones to determine the solar-air degree-days. The heating and cooling energy requirements for different climates were compared by DeST (Designer’s Simulation Toolkit) simulation and the solar-air degree-day method. Approaches to decrease energy consumption were developed. The results showed that the maximum relative error was less than 10%, and the new method was not significantly different from the DeST simulation ( >0.05). The accuracy of calculating energy requirements was improved by the solar-air degree-day method in the different climate zones. Orientation and surface color effects on energy consumption need to be considered, and external walls of different orientations should have different surface colors.

关键词: base temperature     energy consumption     solar radiation     orientation     surface color    

simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence of excess air

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

《能源前沿(英文)》 2012年 第6卷 第3期   页码 296-303 doi: 10.1007/s11708-012-0191-0

摘要: The progression of ignition was numerically simulated with the aim of realizing a full-scale tiny-oil ignition burner that is identical to the burner used in an 800 MWe utility boiler. The numerical simulations were conducted for four excess air ratios, 0.56, 0.75, 0.98 and 1.14 (corresponding to primary air velocities of 17, 23, 30 and 35 m/s, respectively), which were chosen because they had been used previously in practical experiments. The numerical simulations agreed well with the experimental results, which demonstrate the suitability of the model used in the calculations. The gas temperatures were high along the center line of the burner for the four excess air ratios. The flame spread to the burner wall and the high-temperature region was enlarged in the radial direction along the primary air flow direction. The O concentrations for the four excess air ratios were 0.5%, 1.1%, 0.9% and 3.0% at the exit of the second combustion chamber. The CO peak concentration was very high with values of 7.9%, 9.9%, 11.3% and 10.6% for the four excess air ratios at the exit of the second combustion chamber.

关键词: numerical simulation     tiny-oil ignition burner     pulverized coal     temperature field    

参数自寻优模糊控制器在中央空调温度控制系统中的应用

吴爱国,杜春燕,宋晓强

《中国工程科学》 2004年 第6卷 第11期   页码 84-87

摘要:

在中央空调温度控制系统中设计应用了一种参数自寻优模糊控制器。针对中央空调温度控制系统被控对象非线性、大滞后和时变等特点,该模糊控制器在规则可调整模糊控制器基础上引入了加权因子α和比例因子Ku的在线调整优化算法。运行结果表明,这种算法增强了系统的鲁棒性,在不同工作条件下,系统保持了良好的控制品质。

关键词: 中央空调系统     温度控制     模糊控制器     参数自寻优    

埋地热油管道运行参数的准周期变化

崔慧

《中国工程科学》 2006年 第8卷 第1期   页码 51-53

摘要:

从理论上分析了在大气温度变化的影响下埋地热油管道的运行参数以及周围土壤环境均随季节变化而呈现准周期变化规律,在分析大量实际运行数据的基础上,进一步验证了该规律的合理性,建议在有关管道的节能降耗、优化运行以及经济清蜡等问题的研究中,应该考虑运行参数的滞后影响。

关键词: 热油管道     大气温度     土壤环境     准周期    

Intercontinental transport of air pollution

Lin ZHANG,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 20-29 doi: 10.1007/s11783-010-0014-7

摘要: There is an increasing interest on the intercontinental transport of air pollution among the three main emission regions at northern mid-latitudes: North America, Europe, and East Asia. Air pollutants with sufficient long lifetime can be transported from one continent to another. Observations from ground sites, aircraft and satellites have demonstrated this intercontinental-scale transport of air pollutants in the free troposphere. Numerical models have been applied to understand the pathways of the transport and the impact of intercontinental pollution transport. This paper reviews current observational evidence and modeling studies of intercontinental transport of ozone and its precursors, and the resulting impacts on air quality.

关键词: intercontinental transport     ozone     air pollution    

Health impacts of air pollution in China

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1367-1

摘要:

•Impacts of air pollution on various body systems health in China were highlighted.

关键词: Health impacts     Air pollution     China     Advances    

标题 作者 时间 类型 操作

“Partial pressures” of humid air in wide pressure and temperature ranges

Zidong WANG, Hanping CHEN, Shilie WENG

期刊论文

Improvement of part-load performance of gas turbine by adjusting compressor inlet air temperature and

期刊论文

Experimental and kinetic study on laminar flame speeds of ammonia/syngas/air at a high temperature and

期刊论文

空调客车内温度控制系统仿真研究

于梅春,张登春

期刊论文

Effect of extrusion temperature on the physical properties of high-silicon aluminum alloy

YANG Fuliang, GAN Weiping, CHEN Zhaoke

期刊论文

An indirect evaporative chiller

Xiaoyun XIE, Yi JIANG,

期刊论文

Industrial-scale investigations on effects of tertiary-air declination angle on combustion and steamtemperature characteristics in a 350-MW supercritical down-fired boiler

Xiaoguang LI, Lingyan ZENG, Hongye LIU, Yao LI, Yifu LI, Yunlong ZHAO, Bo JIAO, Minhang SONG, Shaofeng ZHANG, Zhichao CHEN, Zhengqi LI

期刊论文

综合空气污染和非适宜温度相关死亡风险构建空气健康指数

张庆丽, 陈仁杰, 印冠锦, 杜喜浩, 孟夏, 邱杨, 阚海东, 周脉耕

期刊论文

Field measurements on microclimate in residential community in Guangzhou, China

Zhuolun CHEN, Lihua ZHAO, Qinglin MENG, Changshan WANG, Yongchao ZHAI, Fei WANG,

期刊论文

An optimized solar-air degree-day method to evaluate energy demand for poultry buildings in different

Yang WANG, Baoming LI

期刊论文

simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence of excess air

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

期刊论文

参数自寻优模糊控制器在中央空调温度控制系统中的应用

吴爱国,杜春燕,宋晓强

期刊论文

埋地热油管道运行参数的准周期变化

崔慧

期刊论文

Intercontinental transport of air pollution

Lin ZHANG,

期刊论文

Health impacts of air pollution in China

期刊论文