磨煤机热风量的计算在Excel文档中的应用

针对磨煤机在喷煤制粉系统中的应用,建立起一套有关磨煤机烟气出入口热风量与磨煤机制粉产量等其它基本参数之间的数学模型以及其它的相关数学模型,并将这些数学模型应用于Excel文档中,以方便于各种热风量的计算、主排风机最大风量及烟气炉最大气量等参数的确定。

基于工作区有效散热量系数确定橡胶硫化车间排热通风量

结合实际工程,分析了理想补风条件下单台硫化机的有效散热量系数与排热通风量和设备散热量的关系,并探讨了排风口高度和围挡高度对有效散热量系数的影响。对实际采用两端集中补风方式的硫化机生产线,引入修正系数对单台硫化机理想补风下的有效散热量系数进行了计算,得到了系统所需的最小总排热通风量。研究结果表明,当硫化机的台数为1,7,14,21台时,对单台硫化机通风量的修正系数分别为1.00,1.36,1.45,1.64。

1000MW机组热二次风量可靠性优化

依据江西大唐国际抚州发电有限责任公司(以下简称"抚州电厂")的实际情况,介绍了热二次风量在总风量计算中的应用方式,描述了总风量低MFT主保护的设计方法,同时介绍了热二次风量在工程阶段的设计缺陷及投产应用中存在的问题,分析了问题存在的原因,阐述了新的设计思路和问题解决办法,在保证机组安全稳定的前提下,合理的兼顾了改造的经济型。

地铁站台门漏风量特性分析

利用一维数值模拟软件建立了地铁线路一维通风网络模型,对列车停站时间、行车周期、轨行区排风量等因素影响下的地铁站通风量进行了分析。行车周期120 s、144 s、180 s、360 s时,停站时间由20 s增至40 s,站台门平均进风量增加约31.39%~40.74%,站台门平均出风量增加约为10.23%~15.16%。行车周期由120 s增至360 s时,站台门平均进风量下降约73.46%。行车周期120 s时,当站台每侧轨行区排风量由30 m3/s增至50 m3/s,站台门平均进风量下降约为30.46%~34.07%。站台门平均出风量增加约为33.10%-34.46%。

全截面矩阵式流量测量装置在1000MW级工业锅炉的应用

二次风量测量的准确性为锅炉燃烧的安全性、经济性以及环保性提供有效支撑,同时也关系到送风控制系统的动态性能。文章聚焦大型工业锅炉二次风量测量问题。首先阐述二次风量测量准确性对锅炉燃烧的重要意义,指出当前由于风量测量装置选型等原因,测量值不准确,影响燃烧控制。其次分析某厂工业锅炉现状及故障现象,如机组运行中热二次风量多次出现缺陷和大幅波动,为机组正常运行带来巨大隐患。通过原因分析,明确原有测量装置正压侧取样问题。最后介绍组织实施过程,包括将测量装置改造为全截面多点等距自清灰防堵装置,进行风量标定。最终解决了二次风量波动问题,提高了机组性能,为能源保供奠定设备基础。

大空间建筑冬季热回收利用的节能分析

大空间建筑冬季易出现垂直温度分层现象,根据这一特点,提出将上部空间热空气直接抽送至人员活动区的热回收方案,建立上下区域的温度差与热回收风量之间的权衡关系,获得了该方案下的理论最优热回收风量区间。并通过典型铁路客站公共区域的模拟计算,表明了实际最优热回收风量是在理论最优热回收风量区间内,得到了其热回收的节能潜力。

基于贝叶斯网络的变风量末端故障诊断方法

针对压力无关再热型变风量末端的15种典型故障,提出了一种基于贝叶斯网络的故障诊断方法。根据某建筑实际运行系统建立了Dymola仿真模型,并基于模拟故障数据对所提出的诊断方法进行了验证。结果表明,该方法对于绝大多数故障都可以成功检测并分离,有着较高的准确性和可靠性,并且可较好地应对实际工程中存在的数据问题,将实时故障诊断的应用场景进一步推广。

自然通风技术的节能原理与应用方法

本文是建筑自然通风研究的一篇综述,其中从自然通风的流动模型、人体热舒适性模型、通风量预测模型三个角度分析总结了近几年的研究成果,可为自然通风研究人员提供参考与借鉴。

An approach to prediction of the South China Sea summer monsoon onset

In the present paper, correlation between the South China Sea summer monsoon （SCSSM） onset and heat content in the upper layer of the warm pool in the western Pacific Ocean is examined using the Scripps Institution of Oceanography dataset for the period of 1955-1998 and an approach to prediction the SCSSM onset is proposed. Correlation showes that there exists interdecadal variability of the SCSSM onset demarcated by 1970 with the largest correlation coefficient in the area west of the center of the warm pool rather than near its centers, implying certain effect from other factors involved besides ENSO. As the correlation is poor for the period before 1970, the heat content anomaly of the warm pool after 1970 is used to indicate early or late onset of the SCSSM beforehand. An ideal representative area （1°×1°） for the warm pool heat content was determined with its center at 3°N/138°E. The nearest TAO （TAO-Tropical Atmosphere Ocean-array） mooring to the center is at 2°N/137°E, and chosen to calculate the heat content for prediction. It is suggested that the TAO mooring at 2°N/137°E could be used to predict the SCSSM onset with the heat content in the upper layer, if the correlation between the SCSSM onset and the heat content of the warm pool runs like that of after 1970. On the other hand, if the situation does like the one before 1970, the representative station is determined at 13°S/74°E with relatively poor correlation, meaning that the warm pool in the western Pacific Ocean plays more important role in the SCSSM onset than the Indian Ocean.

商业厨房排风设计参数对比与论证

我国商业厨房排风量的设计计算长期存在对象不明确和方法不完善等问题,在实际工程中产生了诸多矛盾和不便。本文梳理了商业厨房总排风量和局部排风量之间的关系,明确了各自的适用阶段。在此基础上,对中外现行的基于换气次数的总排风量计算方法和局部排风量计算方法分别进行了整理分析,指出了我国现有方法存在的不足,提出了改进建议。此外,本文还对全面排风量的运行策略和风量计算进行了探讨。最后,基于CFD模拟方法对前述局部排风量方法进行了校核计算,同时验证了全面排风的运行策略。本文结论有助于完善我国商业厨房通风设计体系,弥合设计与实际工程需求间的差异。

Research on the Response of the Upper Layer Heat Structure in the Western Pacific Warm Pool to the Mean Madden-Julian Oscillation

By using the long-term observed hydro-meteorological data (1985-2002) from the Tropical Atmosphere Ocean System (TAO) during the international Tropical Ocean and Global Atmosphere (TOGA) experiment, the key parameters of the Sea Surface Temperature (SST), thermocline depth, surface sensible heat flux and latent heat flux, and the pseudo wind stress in the Westen Equatorial Ocean are calculated in this paper. On the basis of the calculation, the response of upper layer heat structure in the Westen Pacific Warm Pool to the mean Madden-Julian Oscillation (MJO) and its relation to the El Nio events are analyzed. The results show that within the MJO frequency band (42-108 d), the distributions of sea surface wind stress and upper ocean temperature have several spatial-temporal variation structures. Among these structures, the type-I surface pseudo wind stress field plays the role of inhibiting the eastward transport of ocean heat capacity, while the type-II strengthens the heat capacity spreading eastward. Therefore the type-II surface pseudo wind stress field is the characteristic wind field that provokes El Nio events. During calm periods (July-September) of the wind stress variations, the sensible and latent heat capacity fluxes change considerably, mostly in the region between 137°-140°E, while to the east of 150°E, the heat capacity flux changes less.\ In the mean MJO state, the type-I surface pseudo wind stress field structure dominates in the Western Pacific. This is why El Nio events can not occur every year. However, when the type-II and type-III surface pseudo wind stress field structures are dominant, an El Nio event is likely to occur. In this case, if the heat capacity of the Western Pacific Warm Pool is transported eastward and combined with the Equatorial Pacific heat capacity spreading eastward, El Nio events will soon occur.

Characteristics of Thermal and Geopotential Height Differences Between Continent and Ocean and Its Role in the Strength of the Asian Summer Monsoon

The interdecadal factors affecting the summer monsoon winds over Somalia and the South China Sea were studied. Global geopotential heights and wind velocity fields of the 850-hPa and 200-hPa pressure levels, as well as sea surface temperature anomaly data and correlation coefficients were analyzed. The monsoons over Somalia and the South China Sea were found to be two different monsoon systems, operating on different mechanisms and being affected by different oceanatmosphere interactions. The intensity of the Asian subtropical summer monsoon is influenced by the intensity of the summer monsoon over Somalia in the month of June and by the intensity of the summer monsoon over the South China Sea in the months of June and July. The summer monsoon wind strength over Somalia is affected by regional factors, such as the heating of the Tibetan plateau, and by global mechanisms, such as the subtropical heat exchange with Antarctica. The summer monsoon over the South China Sea is affected by different ocean-atmosphere interactions. The Somalia and subtropical summer monsoons have wind blowing down the pressure gradient from area over ocean to that over land, like typical summer monsoons. The South China Sea summer monsoon has winds that blow down the pressure gradient from area over land to that over ocean. The South China Sea summer monsoon is affected by the Kuroshio Current off the east coast of Japan.

Effects of Drying and Blanching on the Quality of Toona sinensis

[Objective]To explore the best T.sinensis processing technology.[Method]The T.sinensis was treated by hot wind drying,freeze drying and blanching,and the contents of ascorbic acid,total phenolics and nitrite were determined respectively before and after the treatment to be a standard to evaluate the influence of different processing methods on the quality of T.sinensis.[Result]Both drying and blanching produced certain impact on the contents of all three components,among which the content of ascorbic acid was slightly influenced by vacuum freeze drying and short-time blanching,but greatly affected by long-time blanching and hot wind drying;the loss rate of polyphenols was above 60% when the hot wind drying,freeze drying and blanching lasted for more than 5 min,while it experienced little change under short-time blanching;hot wind drying and blanching may greatly reduce the content of nitrite,however,the vacuum freeze drying even improved the content,which would produce adverse impact on food safety.[Conclusion]Short-time blanching is the best method to process T.sinensis,it can effectively reduce its content of nitrite and retain the nutrients.

An Observational Study of Typhoon Imbudo in 2003

Typhoon Imbudo was a super-typhoon over the northwestern Pacific in 2003. It caused tremendous damage when it made landfalls in the Philippines and China. This paper documents observational analyses of Typhoon Imbudo during its landfall in China. All available observations are used to study its motion, intensity changes, convection, structure and precipitation. Best-track data indicate that Imbudo moved west-northwestward until 1800 UTC 23 July and then turned northwestward. FNL (final) analysis data show that the motion of Imbudo is dominated by changes of the subtropical high. At Imbudo's mature stage, the minimum sea level pressure dropped to 910 hPa and the maximum sustained winds were as high as 67 m s 1, which is the intensity of a super-typhoon. The surface wind field exhibited asymmetric characteristics. Polar-orbiting satellite imagery also manifested convective asymmetry before Imbudo made landfall in China. Analyzed the vertical wind shear, it is shown that the convection has a downshear-left pattern. All kinds of precipitation data were used to identify the asymmetric characteristic of the rainfall associated with the Imbudo. The maximum rainfalls were located in the southern boundary area between Guangxi and Guangdong. However, the lack of in situ observations limited further analyses of this typhoon.

大型客船厨房空调通风系统设计计算

一般商船的厨房空调通风系统设计都是按确定空调送风温度、以及排出厨房辐射散热和换气次数的风量计算来考虑的,并没有涉及怎么有效地排除厨房烹饪设备在烹饪过程中产生的油烟、异味以及水蒸气,厨房通风效果往往达不到预期效果。大型客船厨房由于厨房种类数量繁多,且单个厨房面积较大、所需集气罩数量和类型也比一般商船的厨房要多,厨房空调风量的确定不能简单的按照换气次数和设备辐射散热量来算,还应充分考虑烹饪设备对集气罩排风量的要求。文章介绍了厨房集气罩排风量的计算方法,通过研究集气罩下面的不同烹饪设备的加热热源、烹饪设备加热功率及不同烹饪设备类型的散热特性,对于每个烹饪设备在烹饪过程中产生的油烟和异味、蒸煮过程中散发的水蒸气等,都需要有针对性的进行处理,分别计算不同烹饪设备工作过程种所需的集气罩排风量,保障厨房的环境。

Effects of spectral nudging on the 2010 East Asia summer monsoon using WRF model

The performance of spectral nudging in an investigation of the 2010 East Asia summer monsoon was assessed using the Weather Research and Forecasting (WRF) model, forced by 1-degree NCEP Global Final Analysis (FNL). Two pairs of experiments were made, spectral nudging (SP) and non-spectral nudging (NOSP), with five members in each group. The members were distinguished by different initial times, and the analysis was based on the ensemble mean of the two simulation pairs. The SP was able to constrain error growth in large-scale circulation in upper-level, during simulation, and generate realistic regional scale patterns. The main focus was the model ability to simulate precipitation. The Tropical Rainfall Measuring Mission (TRMM) 3B42 product was used for precipitation verification. Mean precipitation magnitude was generally overestimated by WRF. Nevertheless, SP simulations suppressed overestimation relative to the NOSP experiments. Compared to TRMM, SP also improved model simulation of precipitation in spatial and temporal distributions, with the ability to reproduce movement of rainbands. However, extreme precipitation events were suppressed in the SP simulations.

Estimations of Net Primary Productivity and Evapotranspiration Based on HJ-1A/B Data in Jinggangshan City, China

Net primary productivity （NPP） and evapotranspiration （ET） are two key variables in the carbon and water cycles of terrestrial ecosystems. In this study, to test a newly developed NPP algorithm designed for H J-1 A/B data and to evaluate the usage of HJ-1 A/B data in the quantitative assessment of environments, NPP and ET in Jinggangshan city, Jiangxi province, are calculated using H J-1 A/B data. The results illustrate the following： （1） The NPP and ET in Jinggangshan city in 2olo both show obvious seasonal variation, with the highest values in summer and the lowest values in winter, and relatively higher values were observed in autumn than in spring. （2） The spatial pattern indicates that the annual NPP is high in the southern area in Jinggangshan city and low in the northern area. Additionally, high NPP is distributed in forests located in areas with high elevation, and low NPP is found in croplands at low elevations. ET has no significant north-south difference, with high values in the southeast and northwest and low values in the southwest, and high ET is distributed in forests at low elevations in contrast to low ET in forests in high-elevation areas and in cropland and shrub grassland in low-elevation areas. （3） Compared to the MODIS product, the range of H J-1 NPP is larger, and the spatial pattern is more coincident with the topography. The range of H J-1 ET is smaller than that of the MODIS product, and ET is underestimated to some extent but can reflect the effect of topography. This study suggests that the algorithm can be used to estimate NPP and ET in a subtropical monsoon climate if remotely sensed images with high spatial resolution are available.

Sensible Heating over the Tibetan Plateau Linked to the Onset of Asian Monsoon

Land surface heating of the Tibetan Plateau (TP) plays an important role in the Asian Monsoon system. In this study, the interannual variability of the sensible heat flux over the TP and its connection with the summer monsoon intensity and onset date was examined based on the newly released land "reanalysis" data, produced by NASA Global Land Data Assimilation System. Although correlation analyses don't show a significant relevance to the summer monsoon intensity, the interannual anomalies in sensible heating near the south flank of the TP indicate a weak reversal in the relationship with the onset date of the West Pacific East Asian monsoon. A diagnostic study shows that above (below) normal sensible heating over the south flake of the TP will lead to rapid (slow) warming of the upper air column over the TP and early (later) reversal of (overturn) the meridional temperature gradient and the vertical wind shear. This will further lead to an earlier (later) onset of the Asian Monsoon.

Venting Design for Di-tert-butyl Peroxide Runaway Reaction Based on Accelerating Rate Calorimeter Test

In order to design the relief system size of di-tert-butyl peroxide(DTBP) storage tanks,the runaway re-action of DTBP was simulated by accelerating rate calorimeter(ARC).The results indicated that under adiabatic conditions the initial exothermic temperature was 102.6 ℃,the maximum self-heating rate was 3.095×107 ℃·min-1,the maximum self-heating temperature was 375.9 ℃,and the pressure produced by unit mass was 4.512 MPa·g-1.Judged by ARC test,the emergency relief system for DTBP was a hybrid system.Based on Design Institute for Emergency Relief System(DIERS) method,the releasing mass flow rate W was determined by Leung methods,and the mass velocity G was calculated by two modified Omega methods.The two relief sizes calculated by monograph Omega method and arithmetic Omega method are close,with only 0.63% relative error.The monograph Omega method is more convenient to apply.

Difference in the influence of Indo-Pacific Ocean heat content on South Asian Summer Monsoon intensity before and after 1976/1977

Monthly ocean temperature from ORAS4 datasets and atmospheric data from NCEP/NCAR Reanalysis I/II were used to analyze the relationship between the intensity of the South Asian summer monsoon(SASM) and upper ocean heat content(HC) in the tropical Indo-Pacific Ocean.The monsoon was differentiated into a Southwest Asian Summer Monsoon(SWASM)(2.5°–20°N,35°–70°E) and Southeast Asian Summer Monsoon(SEASM)(2.5°–20°N,70°–110°E).Results show that before the 1976/77 climate shift,the SWASM was strongly related to HC in the southern Indian Ocean and tropical Pacific Ocean.The southern Indian Ocean affected SWASM by altering the pressure gradient between southern Africa and the northern Indian Ocean and by enhancing the Somali cross-equatorial flow.The tropical Pacific impacted the SWASM through the remote forcing of ENSO.After the 1976/77 shift,there was a close relationship between equatorial central Pacific HC and the SEASM.However,before that shift,their relationship was weak.