Practical Probing Into Gas Instantaneous Water Heater with Condensation

According to the theoretical analysis of energy saving effectiveness of gas instantaneous water heater with condensation, the relationship between heat efficiency and flue temperature of natural gas instantaneous water heater with condensation has been obtained through experiment.Experiment results show that the natural gas instantaneous water heater with condensation has a high practical value.     

Analysis of Sewage-water Heat Exchanger withthe Function of Auto-de-fouling

A sewage-water shell-tube heat exchanger with the function of de-fouling was proposed and designed for sewage-source heat pump. Its new simulation program which relies on a distribution parameter computational method was set up. Then the model was solved with the method of Matrix Control. Based on the model, the distribution of bilateral fluid temperature were studied, under the conditions of different flow rates and heat exchange area before and after the de-fouling. Results showed that there will be heat anti-transfer phenomenon if the heat exchanger area is bigger than need and the region of this phenomenon was point out. Setting the function of auto-de-fouling in shell-tube heat exchanger and reducing the equipment's volume accordingly can make the sewage-water heat exchanger run in the best conditions.     

Numerical Analysis and Optimization of a Small Vehicle Heat Exchanger

This paper analyzes the fluid flow and heat transfer of the heat exchanger, and obtainsd the distribution of fluid field, heat field and pressure field in heat exchanger. According the analysis result, some modify measure is adopted, such as decreasing the number of tube bundle, the size of baffle plate and increasing the diameter of exchange heat tube. In the new heat exchanger, the resistance decreased 32.3%, is 103.2 Pa and the temperature of the exit is 130 K. The new heat exchanger satisfies the requirement of exchanging heat. The study indicates that adopting the numerical simulation method could get temperature, pressure and fluid - velocity of anywhere of the heat exchanger, and understand effecfing of structure parameter on fluid flied and heat flied of the heat exchanger. Therefore, it provides a new method for optimization design of heat exchanger.     

Study on Heat Transfer Characteristics in Waste Gas of the Exchanger

By the calculation and experiment,analysed the heat transfer characteristies in waste gas of the high temperature exchanger.The results which the reasonable vertical and horizontal distances were obtained,these turned out that the metallic rediation net was the effectve method intensified heat transfer in hot waste gas.The infulence of the velcity and temperature of waste gas on the multiple heat transfer caefficrent of the exchanger was studied by the experiment data.     

深部逆断层圆弧形断面诱发煤岩动力灾害的力学分析

为了探索逆断层附近易于发生煤岩动力灾害的力学机制,构建了由构造应力为主导的圆弧形断层面简化力学模型,得到了构造应力以及由其引起附加垂直应力的分布规律,进而建立了断层上盘逆冲滑动临界角度的数学模型。研究表明：水平构造应力与附加垂直应力随着断层倾角的增大而增大,当断层倾角接近90°时,附加垂直应力突然增大且其值数倍高于水平构造应力;基于逆断层滑动的力学分析,理论计算了煤层沿断层逆冲滑动的临界角度,这将对煤岩动力灾害的危险性预测有一定的参考意义。     

Dropwise Condensation Heat Transfer Coefficient on the Horizontal Circular Surface with Radial Gradient Surface Energy

A theoretical model is developed for the dropwise condensation heat transfer on the horizontal circular surface with radial gradient surface energy based on the heat transfer model of individual condensate drop and the size distribution model of condensate drop on homogeneous condensation surface.The effect of variation of contact angle on the gradient surface on condensation heat transfer and condensate drop size distribution is taken account of in this model.The theoretical calculation method was obtained to predict the dropwise condensation heat transfer coefficient on the horizontal circular surface with radial gradient surface energy under various wall subcooled temperature,contact angle profile on wall surface,and working fluid.The effects of surface energy gradient,wall subcooled temperature,and thermophysical properties of condensate on the condensation heat transfer are discussed respectively.The calculation results show that the condensation heat transfer coefficient increases slightly with the increase of wall subcooled temperature.As latent heat and surface tension increasing,the condensation heat transfer coefficient increases.A larger surface energy gradient induces a larger condensation heat transfer coefficient.     

Research of Flow Characteristics of Multi-jets in the Same Direction and in Great Velocitv Difference in Combustion Chamber

The flow characteristics of multi-jes in the same direction and in great velocitydifference in combustion chamber were researched by the cold mould simulating test of self-designedlow- calorie value gas burner.The results showed that the large negative pressure region and back-flow region would be produced by the multi-annular jets with high-velocity air involve intensivelythe central low-velocity gas jet and by virtue of the small main air volume resulting by some extentcirculation of gas jet.These have the advantage of realising homogeneously mixing between air jetsand gas jet and combusting steadily.     

Visual Experiments on Bubble Growth and Departure at the Open Tip of Two Capillary Tubes Connected with a Gas Chamber

The bubble growth and departure at the open tip of two capillary tubes joined with a gas chamber was investigated by using a high-speed video imaging system. The experimental results showed that the capillary tube with larger size and hydrophilic property act as the liquid flow channel while the one with smaller size and hydrophobic property as the gas flow channel when liquid submerged the tip of the two capillary tubes without internal gas flow. In contrast, the larger capillary tube become a gas flow channel and the smaller one a liquid flow channel when liquid submerges the tip of the two capillary tubes with internal gas flow. The bubble departure period significantly decreases and the bubble departure diameter eeps in gentle increase with the increase of the flow rate of gas injected into the gas chamber. The liquid flow rate in test section has a significant effect on the bubble growth and departure. A larger liquid flow rate led to a higher bubble departure frequency and a larger bubble departure diameter. At a larger liquid flow rate, the bubble growth and departure at the tip of the upstream capillary become faster, which result in the liquid return at the tip of the downstream capillary tube.     

大型粮仓玉米就仓干燥的微生物危害控制技术

研究了超过1000t规模的大型粮仓高水分玉米就仓干燥新技术.整套处理系统由微生物活性快速检测仪、移动式局部处理机、空气加热器及臭氧发生器等组成.利用微生物活性快速检测装置监测仓内高水分玉米在系统升温和通风降水过程中的微生物活动状况,并根据微生物活性检测结果制定通风、加热的参数,控制通风气流中臭氧的添加量,达到有较控制玉米中微生物危害的目的.     

沈阳周边城市群大气污染物的输送场分析研究

主要采用MM5数值模式模拟分析沈阳及其周边的辽阳、抚顺、鞍山和本溪地区大气污染物输送场。结果表明该区域大气环境的输送场分布特征是：冬季和秋季流场形式是西北气流为主导,大气污染物从西北向东南输送;春季和夏季该区域的流场形式是以西南风盛行,大气污染物从西南到东北方向输送,但夏季的风速高于春季,输送程度较春季强。由于流场分布、逆温及逆湿等原因,该区域的冬季大气污染物浓度最高。     

Analysis of the Ground Adjustment Ability of the Ground Source Heat Pump Systems in Winter

Based on an actual ground source heat pump system in hot summer and cold winter area, the system operation parameters were tested for 6 years under the state of using cooling tower for cooling in summer but the ground heat exchanger and fire pool for heating in winter. A three dimensional (3D) tube group model was established, and the thermal balance analysis and calculation of the ground temperature distribution around the ground heat exchanger were conducted by the numerical calculation. According to the comparison between the test data and the theoretical results, the influencing factors of the ground adjustment ability were obtained.     

燃煤烟气脱硫废弃物改良土壤种植沙枣效果研究

为了有效利用燃煤烟气脱硫废弃物(简称脱硫废弃物),探究沙枣作为改良盐碱地先锋树种的可行性。笔者采用大田试验的方法,从土壤pH值、全盐含量、碱化度（ESP）和常见离子相对含量的变化等方面,研究了脱硫废弃物改良后龟裂碱土种植沙枣的效果。结果表明：随着林木生长时间的延长,脱硫废弃物改良后的土壤pH值、可溶性盐和碱化度（ESP）均有不同程度降低,pH值、可溶性盐和碱化度（ESP）分别由初始的9.50、46 g/kg和5.3%下降到8.31、11.4 g/kg和3.1%;脱硫废弃物改良土壤种植沙枣,且达到3年,土壤的改良效果最为明显。以上结果表明,脱硫废弃物可有效降低土壤中交换性钠、交换性镁的相对含量,降低其对植物的毒害作用,改善土壤化学性质,从而有利于林木的生长和发育。     

平房仓空调控温安装方式的探索

在富氮低氧储存条件下,对平房仓内气囊薄膜上下形成的空间,进行了三种不同空调控温安装方式的试验,试验结果表明,采用蒸发器(室内机)(不带风机)+中压风机组合,利用PVC管道及管道上开孔来输出冷气和回送气体,形成内部循环式的气流空调控温安装方式,可以有效控制平房仓的仓温。     

Investigation and application of jet aeration technology in the oxidation process of desulfurization slurry

The calcium sulfite oxidation rate is an important indicator to judge the efficiency of wet limestone/gypsum flue gas desulfurization process used by high-sulfur-coal power plant. Jet aeration technology which integrates aeration and stir into one apparatus is proposed to implement the forced oxidation of limestone/gypsum flue gas desulfurization in order to improve the oxidation rate. The working principle of jet aeration oxidation in desulfurization slurry is investigated. ANSYS CFX is used to simulate the flow field inside the desulfurization slurry tank and obtain the best installation method of jet aerator which makes the mixing and stirring effect of slurry ideal: 3 jet aerators are uniformly installed at the height of 0.8m up from the bottom of slurry tank with their axis perpendicular to the tank wall. The air suction flowrate of jet aerators is tested under the best installation method in the on-site application test of the X protection company of Chongqing. The oxidation rate of calcium sulfite in desulfurization slurry is also tested by using iodometric method. The results show that the total air suction flowrate of jet aerators is 59.52 m 3/h which meets the requirement of slurry oxidation air quantity and the oxidation rate of calcium sulfite in desulfurization slurry reaches 87.6% after two-hour oxidation by using jet aeration.     

褪黑激素对蓝狐卵泡发育的影响研究

为探索褪黑激素对蓝狐卵泡发育的影响,为研究蓝狐卵巢卵母细胞的利用提供依据。试验分别对埋植褪黑激素蓝狐的卵巢和发情期卵巢的形态及卵泡直径进行测量和比较,并采集卵母细胞进行体外成熟培养,每12 h观察并记录培养结果。结果表明：埋植褪黑激素蓝狐卵巢的体积和重量与发情期相比差异极显著(P<0.01);其各级卵泡直径均小于发情期,其中次级卵泡差异显著(P<0.05);体外成熟培养48 h后的卵丘扩散率显著小于发情期(P<0.05)。     

Degital Simulation for the Direct Torque Control of Induction Motors Using the Circle Flux Path

This paper introduces the importance of developing the Ground-Source Heat pump and describes the prospects of it.with the method used abroad to acquire the temperature profiles within surrounding soil of the underground heat exchanger with buried tubes, in this paper the line heat source theory and thermal resistance network analysis method were used to set up the heat transfer model.The original temperature of the ground is determined by calculation and is compared with test results. Experiments of running single tube and running three series connection tubes are carried out on the built underground exchangers of vertical buried tube type.And the data which can provide reference for the Ground-Soure Heat pump technique are acquired.     

Cold Simulated Experiment of Mixed Condition in Boiler Using Gas Reburning for NOx Reduction

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.     

Constant Temperature Control System for Gas Water Heater Based on Fuzzy Reasoning Arithmetic

Basing on Fuzzy reasoning technology, this paper introduces the work flow of Gas water heater, and the trait of papilionaceous valve. It also describes the designing process of Fuzzy controller, its theory and the method of making parameter. The experiment results show that this temperature control system has better characteristics such as high- precision, good dynamic performance, excellent control effect, and so on. The design shows its validity and practicability.     

Numerical Simulation of Fluid Flow in Converter Combined Blown Bath

The fluid flow mathematic models in converter combined blown are set up.It is simulated for flow state and velocity distribution of gas and stir action in different behaviours of bottom blown,top blown and combined blown by software PHOENICS(Parabolic Hyperbolic or Elliptic Numerical Integration Codes Series).In normal operation condition of ejection guns,the fluid flow in bath is axisymmetric three-dimensions flow.The results reveal out dynamic main area and slowness cyclone zones,also asked dead zone abating or erasing in practice.These shows that bottom blown gun ought to 0.5~0.7 circumference diameter of fused bath using top-bottom combined blown process.     

STUDY ABOUT FLOW THEORY AND GOVERNING EQUATION OF GAS SEEPAGE FLOW IN COAL BEDS

This paper analyzes comprehensively the present approaches about the flow theory and governing equation of the gas seepage in China from the equations of the gas flow continuity, motion, state ane content. The viewpoint is put forward in the paper that the gas amount taking part in seepage flow is only a part of the whole gas content. The governing equation, of gas seepage flow in coal seams is set up on condition that procedures of adsorption and desorption are convertible completely.