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1.
Using modular simulation technique,a mathematical model for the combustion and air/gas system of the W shape flame boiler is presented.The experimental resulats show that.The dynamic process accords with the mechanism process of the object.  相似文献   

2.
The principle of NO x reduction using gas reburning in boiler is analyzed. The experimental device is set up according to the principle of cold simulation. Replacing natural gas with hot air, the cold simulated experiment of mixed condition in boiler has been done. The method reflecting the mixed condition in boiler by means of surveying the uniformity of temperature is put forward on the basis of the similarity of momentum, heat and mass transfer processes. In the meantime, the temperature of different sections in furnace is measured and mean square difference of temperature field is calculated. The effect of flow rate and position of nozzle on the mixed condition in boiler is investigated.  相似文献   

3.
A mathematical model is presented to describe the fluiddynamics processes for the combustion system of 410t/h Pyroflow CFB boiler.A core annulus structure with solid dispersion from core to annulus is considered,and the influence of coal particles fragmentation,attrition and broad size distribution of feeding coal and bed inventory on hydrodynamics is specially taken into account.The simulation results show that the CFB boiler has good hydrodnamic characteristics and high hot cyclone efficiency.  相似文献   

4.
A cold model (its ratio is 1:12.5) of a 50 MW tangentially pulverized coal-fired boiler was built and the mixture characteristic between a simulating gas (hot air) and a main airflow (cold air) were gotten at different ejecting methods and quantities of the simulating gas through measuring the temperature pattern distributing in the furnace of the model. The simulating gas spouted from front and rear walls resulted a more even mixture characteristic, and the tangentially ejected simulating gas is more suitable for the tangentially pulverized coal-fired boiler, and the tangentially ejected OFA is also of advantage to it. The effect of quantities and locations of the simulating gas on the mixture characteristic was also discussed.  相似文献   

5.
Coal fired chain grate boiler is retrofitted to coal bed methane boiler. The flow, combustion and NOx emission characteristics of low concentrations methane in the boiler furnace are studied by the numerical simulation and experiments. The results show that the axial velocity reaches the maximum at 0.5 m from the nozzle and declines sharply in the range of -0.4~0.4 m on the width direction. With the heat load increases, the position of highest temperature moves to the rear of furnace and the simulation and experimental results agree well. At the front of the furnace, the obvious bimodal distribution of temperature at low heat load along the width direction is found, but it is a single peak distribution at 100% heat load. At the rear of the furnace, the temperature shows bimodal distribution at all kinds of heat loads. Gas temperature at boiler furnace outlet increases linearly with the increasing of heat load but the experimental results are slightly lower than the simulated results. The NOx is mainly produced in the middle and rear of furnace with high temperature, and the position of NOx peak lags far behind that of temperature peak. With the excess air coefficient increases, the highest furnace temperature and NOx generation increases and then decreases.  相似文献   

6.
设计了一套水暖锅炉自动调温系统应用于农业生产,主要部件包括主机、辅机、控制系统和水暖管道装置等。基于PLC的锅炉补水泵控制系统能够对整个锅炉的运行状况进行监测、报警、控制,保证锅炉正常、可靠地运行。该设计克服了以往养殖水暖锅炉中存在的缺陷,可以保证锅炉补水泵控制系统稳定可靠工作。  相似文献   

7.
The burning rate of hydrogen air pre mixture on meso scale is mainly determined by its chemical reaction rate. So a Laminar Finite Rate Model, the gas phase reaction mechanism for the combustion of hydrogen air mixture which consists of 19 reversible elementary reactions and the dynamic mesh method are adopted to simulate the combustion of hydrogen air mixture in a meso scale IC engine which operates a quasi gas power cycle under ultrahigh combustion load. The combustion of hydrogen air mixture on meso scale in the micro combustion chamber with moving boundary can be stable. The complete thermodynamic process of heat addition, internal energy increasing, and a boundary work output producing during expansion can be perfectly achieved in the closed combustion system of the meso scaled IC engine igniting the hydrogen air mixture by wire surface of high temperature. However, running parameters such as cycle period, initial pressure and fuel/air ratio have complex effects on the hydrogen air combustion of micro closed container with moving boundary.  相似文献   

8.
This paper conducts the full size three-dimensional combustion numerical simulation study on the low-calorific value coal bed gas combustor. It explors the effects of different ratios of swirling wind and straight wind on flow field,temperature field and concentration field when this combustor combusts coal bed gas which methane volume concentration is 30 percent. The optimal ratio of swirling wind and straight wind is gained. Based on this,the number and obliquity of cyclone vane in gas pipeline are further optimized. The results show that when ratio of straight wind is 80 percent and ratio of swirling wind is 20 percent,the good jet flow rigidity is not only possessed,but also the strong spin momentum is brought. Reverse axial velocity grads and reverse velocity in central backflow region are also big,the burning temperature and combustion efficiency are high,and high-temperature region is diffusely distributed. When the number and obliquity of cyclone vane are respective 6 and 60,the mass fraction of methane descends quickly,the mass fraction of methane is low in outlet of combustion region,and the combustion efficiency is high.  相似文献   

9.
双层对向正反燃烧单体供热技术在烤烟烘烤中的应用研究   总被引:2,自引:1,他引:1  
为提高烤烟烘烤中燃料利用率,降低烘烤成本,减少环境污染,研究采用1个供热炉设上下2个炉膛,实现正向和反向同时对向燃烧,对比研究了双层对向正反燃烧单体供热设备和普通加热设备烤房烤烟烘烤性能。煤的燃烧充分,传统烟气中所含CO、CH4、碳粉尘等可燃物能得到充分、高效燃烧及利用。空载测试升温速率60℃/h,比普通烤房提高34℃;烘烤实载时,各阶段实测温湿度与目标温湿度吻合度高,完全能满足烘烤工艺的控制要求。双层对向正反燃烧单体供热设备烤房平均每千克干烟耗煤量、耗电量、综合能耗成本分别比普通烤房减少0.31 kg、0.05 kWh和0.33元,降幅分别为17.73%、14.36%和17.46%;烘烤操作等日常用工成本较普通供热设备少0.52元,降幅43.93%,且对烟叶烘烤质量无明显影响。双层对向正反燃烧单体供热设备升温速度快,平面温度均匀,烘烤过程中温湿度控制精准,能有效降低烘烤能耗和用工成本。  相似文献   

10.
《保鲜与加工》2003,(11):23-26
The characteristics of flow and combustion in micro gas turbine engine with the low Reynolds number and the high Mach number, the high Couette number and the low Biot number, as well as the ultra high duty ratio of combustion in very small space are analyzed, which are remarkably distinguished from those on macro scale. At the meantime, the limitation of traditional dynamic lubrication theory at ultra high speed on micro scale is presented, and the possibility of making the gas bearing to be able to work at ultra high speed by utilizing boundary slip is investigated. Due to the applied prospect of silicon carbide in the field of MEMS especially under high temperature and high strength conditions, the technical process of combining silicon etching with reactive sintering and grinding machining of silicon carbide is put forward so that the miniature machining of silicon carbide for micro gas turbine engine becomes possible.  相似文献   

11.
Boiler is an important facility in power plant , the safety and economy of unit is affected by it. Studying the dynamic of boiler can improve the knowledge about boiler , which is important for. Features of MMS are introduced based on MMS simulation setting, and the real time capable module and non real time capable module are compared from principle. Real time capable dynamic model of boiler and non real time capable dynamic model of boiler of 330 MW unit are established . The experimental results show that the dynamic process of two type model accords with the mechanism of the object , at the same time, the validity of real time capable module is discussed .  相似文献   

12.
高效助燃除硫剂在烟叶烘烤中的应用   总被引:1,自引:1,他引:0  
为了降低烟叶烘烤过程中煤炭燃烧时有害气体排放量,改善煤炭燃烧性能,进行了高效助燃除硫剂的应用试验。结果表明:燃煤中添加3%的高效助燃除硫剂能改善燃煤的燃烧性能,使燃煤燃烧更加充分,炉膛内平均温度较对照提高53.67℃,助燃效果明显,有利于提高燃煤利用率,降低能耗。烟叶烘烤时,燃煤中添加3%和1%的高效助燃除硫剂,耗煤量及燃烧时产生的碳氧化物、氮化物及硫化物都有不同程度的降低,其中除硫效果显著。  相似文献   

13.
NGV engine adopts the fuel supply method of premixing natural gas and air in the premixing chamber out of cylinder, which results in the engine dynamic performances decline. It is an obstacle to popularizing and applying NGV. Using air rich in oxygen to support combustion can decrease ignition point of the fuel, enhance combustion efficiency and make much more heat available. The dynamic perfonnances and fuel consumption rate of a NGV engine with different oxygen concentration are researched in detail. The results show that the increase of oxygen concentration has remarkable influence on the dynamic performances of NGV engine. Power and Torque performances increase and fuel consumption rate decreases when oxygen concentration of premixed gas increases. The results of theory analysis and experiment research indicate that combustion-supporting using oxygen-rich air can enhance the dynamic performances of NGV engine.  相似文献   

14.
规模化养猪场废水和废气污染控制研究   总被引:3,自引:0,他引:3  
研究污染治理措施对养猪场废气和废水中污染物浓度的影响,探讨治理措施的可行性,以期为同类型养猪场的污染防治提供参考。采用活性炭吸附和水膜除尘分别处理恶臭气体和锅炉燃烧废气;采用厌氧发酵和CASS工艺处理废水。在活性炭吸附塔进气口和出气口分别采集气体样品a和b,测定气体中氨(NH3)和硫化氢(H2S)的数值;在水膜除尘器进气口和出气口分别采集气体c和d,测定气体中二氧化硫(SO2)和烟尘的浓度。在沼气池进水口采集2 L水样,记作水样A;经过沼气池厌氧发酵20、30、40天后,分别在沼气池出水口采集2 L水样,记作水样B、C、D;在CASS污水处理池出水口采集2 L水样,记作水样E;测定化学需氧量(CODcr)、5日生化需氧量(BOD5)、悬浮物(SS)、氨氮(NH3-N)和总磷(TP)的数值。每次取3个平行样。结果表明:b中氨的强度显著低于a;b中硫化氢的强度极显著低于a;d和c的SO2浓度无显著性差异;d的烟尘浓度极显著低于c。水样B、C、D、E中的化学需氧量、5日生化需氧量、悬浮物的浓度极显著低于A。水样E中,氨氮和总磷的数值极显著低于A、B、C和D;A、B、C、D之间无显著性差异。活性炭吸附处理对氨作用显著,对硫化氢作用极显著;水膜除尘处理对二氧化硫无明显影响,对烟尘作用极显著;单纯的厌氧发酵处理对化学需氧量、5日生化需氧量和悬浮物作用显著,对氨氮和总磷不显著。厌氧发酵和CASS工艺联合处理对化学需氧量、生化需氧量、悬浮物、氨氮和总磷作用极显著。除二氧化硫外,处理后各污染物浓度均能够达标。  相似文献   

15.
Aiming at the questions of raceway section two dimension temperature distribution from two dimensional image accumulated by three dimensional radiation space and three dimensional temperature reconstruction error caused by limited charge coupled device (CCD) sensors for a sudden spread combustion chamber, the two dimension rectangle interpolation virtual CCD sensor installation algorithm is provided as a new technology for solving the difficulties of installing more CCD sensors and filtered back projection reconstruction error caused by limited projection numbers. The radiation intensity projection data got from flame image collected from the installed CCD sensors and computed virtual CCD sensors is interpolated for filtered back projection to computer intensity distribution and calibrated bi color method is used to calculation temperature in raceway depth direction. The results of experiments on a mini type coal gas furnace and practice test showed that the algorithm is accurate and credible and realized the on line monitoring for sudden spread combustion chamber raceway depth direction. At the same time, the useful information is provided for further studying combustion working state for the sudden spread combustion chamber.  相似文献   

16.
It is useful for diagnosing coal combustion status and the tuyere and raceway in blast furnace, at the same time, it is supervision running state to study on temperature-field of also helpful for supervising the structure of oxygen and coal burning apparatus, improving coal combustion technology and coal injection operation. The model between red and green information of true color flame image and temperature is established and two dimension raceway section projection temperature-field are achieved by applying no-touch radiation temperature measurement theory and technology. It is proved with experimentation that the method is effective and feasible, and the testing precision can reach 98.09% compared to the testing result of thermocouple of taking out gas.  相似文献   

17.
Based on the analysis of flowing combustion, gasification reaction, and lumped parameter, a three region model is established to predict the temperature and gas components of Texaco coal gasifier. Using mass balance and energy balance equations to each zone, the model takes account of gas solid two phase flow, coal pyrolysis, radiation heat transfer, and heterogeneous and homogeneous kinetic chemical reactions. Based on the model, a program is developed for dynamic and static simulation. After parameterization and simulation analysis, some important trends and conclusions are attained. Because the model can accurately predict the temperature and gas components in jet region, it has widespread engineering application value.  相似文献   

18.
研究了两步法制备新型固体醇燃料的工艺,详细讨论了各种影响因素,确定了最佳工艺条件:反应温度为70℃,固体醇燃料的化学组分分别为分散剂1.30%,硬脂酸4.76%,NaOH0.62%,工业乙醇90.73%,蒸馏水2.59%。制得的固体醇燃料的熔点为52℃,热值为-28.47kJ/g,火焰最高温度为718℃,其燃烧时不产生黑烟和有害气体,对环境友好。由燃烧实验得到固体醇燃料的燃烧速率方程,从而揭示了固体醇燃料的定量燃烧规律。  相似文献   

19.
锅炉设备在食品工业中的应用范围很广,很多的食品企业都应用锅炉的蒸汽进行加热操作。介绍了中小型食品生产线对锅炉设备的选型标准及安装形式,以及锅炉蒸汽管路与食品生产线成套设备安装的工程监理,以期为在实际生产操作中选择合适的锅炉设备和降低安装成本提供参考。  相似文献   

20.
焦炉集气管压力是炼焦生产过程中重要的工艺参数,其值是否稳定,直接影响到煤气质量、焦炉寿命、焦炭质量和生产环境。针对焦炉集气管压力系统是一个强干扰、非线性和多变量耦合的复杂系统,采用LS-SVM辨识出焦炉集气管压力系统的逆系统模型,并将其串联在原系统之前,运用逆系统的方法将集气管压力系统解耦成2个相互独立的单输入单输出伪线性子系统。同时,对解耦后的系统采用非线性内模控制策略以保证系统的鲁棒性和稳定性。仿真和应用结果表明该控制策略的解耦控制效果较好,提高了系统的快速调节能力和跟踪精度,而且增强了系统的鲁棒性,可以保证焦炉集气管压力稳定在现场工艺要求的范围内。  相似文献   

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