Power Equipment

Archive

  • 2015 Volume 29 Issue 1
    Published: 15 January 2015
      
  • Select all
    |
  • Application of Inlet Air Spray Cooling Technologyto Domestic Gas Turbines
    Gao Nanxing
    2015, 29(1): 1.
    Abstract ( )   Knowledge map   Save
    To reduce the power and efficiency loss of gas turbines in hightemperature seasons, it is an economic and effective way to adopt the inlet air spray cooling technology. An introduction is being presented to mechanism of the technology, calculation of the basic parameters and some data of MeeFogTM spray system from American Michaelis Industries adopted for existing gas turbines in China, which may serve as a reference for relative personnel to promote the application of this technology to domestic gas turbines.
  • Strength Calculation and Structural Improvement for Highpressure Rotor of an AP1000 Nuclear Steam Turbine
    Yang Yu, Wang Yong, Shi Jinyuan, Deng Zhicheng
    2015, 29(1): 7.
    Abstract ( )   Knowledge map   Save
    According to the strength criterion for highpressure rotor of an AP1000 nuclear steam turbine, transient thermal and structure analysis were conducted under steadystate operation, cold startup, warm startup, hot startup and normal shutdown conditions, while strength calculation was performed under 110% and 120% overspeed conditions, based on which 8 positions in the original design was found to be unable to meet the requirements of strength criterion. Through structural improvement, the strength of rotor in optimized design under rated, transient, stress corrosion and overspeed conditions can all meet the strength criterion, proving the final strength design to be qualified, which will be beneficial to longterm operation of the steam turbine.
  • Numerical Simulation on Film Cooling Effect of Gas Turbine Blades
    Shen Jingjing
    2015, 29(1): 11.
    Abstract ( )   Knowledge map   Save
    Turbine blade cooling technologies are very important to the improvement of gas turbine efficiency, among which film cooling is one of the key ways. According to the geometry of the firststage moving and stationary blade of a certain type of gas turbine, a blade model was set up, based on which numerical simulation was conducted to analyze the film cooling technology, with focus on leadingedge film cooling, so as to study the effects of following factors on the film cooling efficiency, such as the blowing ratio, density ratio, free stream turbulence and the jet angle, etc. Results show that poor cooling effect will be resulted if the blowing ratio is too high or too low; highdensity jet stream can be maintained more easily on the surface than lowdensity stream; better film cooling effect can be obtained under lower but not higher turbulence conditions; the cooling effect can be improved by reasonably adjusting the jet angle.
  • Experimental Study on Heat Transfer and Resistance Characteristics  of Helical Serrated Finned Tubes
    Shan Jianming, Lin Zhengchun, Wang Enlu, Wang Lihong, Qu Changwen
    2015, 29(1): 15.
    Abstract ( )   Knowledge map   Save
    Through experimental study on heat transfer and flue gas resistance characteristics at flue gas side of 10 different types of helical serrated finned tubes typically used in actual engineering, correlation formulae were obtained for each type of helical serrated finned tube, so as to provide the basis for calculation of heat transfer and resistance coefficients of the heat recovery steam generator (HRSG). Based on above correlation formulae, the effects of following factors on the heat transfer and resistance characteristics were analyzed, such as the fin spacing, fin height, lateral pitch and tube size, etc., which may serve as a reference for optimizing the structure size of finned tubes, promoting the heat transfer coefficient and lowering the resistance coefficient.
  • Dynamic Simulation Model of Singleshaft HeavydutyGas Turbine Based on Simulink
    Shi Yuheng
    2015, 29(1): 20.
    Abstract ( )   Knowledge map   Save
    The dynamic noniterative simulation model of single shaft heavy duty gas turbine was developed by the objectoriented modularized modeling method in Matlab/Simulink. For highfidelity purposes, the mathematical model takes into account the variation of specific heat with temperature and the effect of thermal inertia of metallic materials in the GT flow passage, except the volume inertia and rotational inertia. Simulation results show that the mathematical model can reflect the system dynamic performance well and has a higher simulation precision, which may be used in the development and testing of control systems for heavy duty gas turbines.
  • Calculation Method for Main Steam Flow of Nozzle Governing Steam Turbines
    Chen Feixiang, Xu Jianqun, Ma Lin
    2015, 29(1): 24.
    Abstract ( )   Knowledge map   Save
    According to the Friuli Greig formula and in combination with field test and theoretical calculation, the relationship between main steam pressure and flow of nozzle governing steam turbine was corrected, which was subsequently verified and applied to a 300 MW nozzle governing steam turbine. Results show that the proposed formula has high precision and high practical values.
  • Study on RubImpact Faults in Large TurboGenerator  Sets under Different Conditions
    Wang Fengliang
    2015, 29(1): 27.
    Abstract ( )   Knowledge map   Save
    Based on 30 cases of rubimpact faults occurring in large turbogenerator sets in the past decade, a statistical analysis was made to the working conditions under which the rubimpact faults happened. Results show that the rate of rubimpact faults is increasing for the first startup after overhaul of large turbogenerator sets, and the rate of rubimpact faults caused by unit operation is increasing too. In combination with actual field cases, characteristics of rubimpact faults in large turbogenerator sets were studied under different working conditions, while main causes leading to the faults were analyzed, and subsequently corresponding countermeasures were proposed, which may serve as a reference for safe operation of large turbogenerator units.
  • Research and Development of Mobile Supervisory System for Thermal Power Plants
    Wang Aijuan, Wang Mingchun
    2015, 29(1): 31.
    Abstract ( )   Knowledge map   Save
    A mobile supervisory system is put forward for thermal power plants based on existing information systems, to which an introduction is presented to the design methods in the aspect of system structure, function and network safety, etc. This may serve as a reference for research and development of mobile supervisory systems for thermal power plants.
  • Design Features of the AP1000 PWR Steam Generator
    Meng Jian, Xu Jinkang
    2015, 29(1): 35.
    Abstract ( )   Knowledge map   Save
    An overview is presented to the history of the AP1000 pressurized water reactor (PWR) Delta 125 (Δ125) steam generator, together with a detail introduction to design features of the steam generator in the aspect of design parameters, materials and structure, etc. It is pointed out that the design of relevant antivibration bars should be verified by actual operation. This may serve as a reference for PWR steam generator designers.
  • Application of Directdrive Largediameter Axial Flow Fanin Aircooling Condensers
    Yin Jiying
    2015, 29(1): 40.
    Abstract ( )   Knowledge map   Save
    To solve the problems occurring in aircooling condensers caused by gearbox drive unit, a scheme is proposed by adopting a directdrive lowspeed permanent magnet synchronous motor to drive the largediameter axial flow fan. Moreover, an introduction is presented to the motor characteristics and the process of developing and testing the 132 kW permanent magnet synchronous motor and 9 144 mm diameter axial flow fan, both of which are used to match a 1 000 MW aircooling condenser unit, while a preliminary analysis is carried out on the unit economic benefit. It has been found that the axial flow fan driven by lowspeed permanent magnet synchronous motor can operate reliably and is able to achieve a remarkable energysaving effect.
  • Combustion Adjustment Test for Water Wall OvertemperaturePrevention of a Supercritical Wflame Boiler
    Zhou Wentai, Cheng Zhihai, He Xiang, Yang Yong
    2015, 29(1): 45.
    Abstract ( )   Knowledge map   Save
    To solve the problems of frequent water wall overtemperature and high carbon content in ash of the No.1 boiler in a power plant, an analysis was carried out, through which the problems were found to be caused by poor combustion at exhaust gas side and unreasonable way of air distribution, leading to the over downward flame. Combustion adjustments were subsequently conducted on following aspects, such as the secondary air distribution, pulverized coal fineness and the exhaust gas valve, etc. Operation results prove above adjustments to be effective, i.e. the water wall overtemperature problem is solved, the thermal load is more uniformly distributed and the carbon content in ash is obviously reduced.
  • Analysis on Economy and Safety of a 660 MW Unit due toAddition of Flue Gas Heat Recovery System
    Liu Tao, Xiong Wei
    2015, 29(1): 49.
    Abstract ( )   Knowledge map   Save
    To reduce the coal consumption for power supply of a 660 MW unit, a flue gas heat recovery system was added and put into operation. Results show that via the heat recovery system, the flue gas temperature at desulfurization tower inlet can be reduced by 3543 K, and the recovered heat can be used to rise the condensate water temperature, thus lowering the turbine heat consumption rate by 6277 kJ/(kW〖DK1〗·h), and the coal consumption for power supply by 28 g/(kW〖DK1〗·h) at most, and accordingly reducing the water consumption of desulfurization system by 40 t/h. Moreover, the lowtemperature corrosion of heattransfer pipes can also be prevented by controlling the lowest tube wall temperature to be higher than the flue gas acid dew point.
  • Cause Analysis and Handling of Impeller Cracking Failurein a Coastal Inclinedflow Circulating Water Pump
    Yu Zhuzhong
    2015, 29(1): 53.
    Abstract ( )   Knowledge map   Save
    Cause analysis was conducted to the impeller cracking failure occurring in a coastal circulating water pump of a 600 MW supercritical power unit according to the cracking phenomenon and relevant data, after which corresponding countermeasures were proposed and taken. In combination with the handling method and effect for similar water pumps, specific treatment measures for impeller cracking of inclinedflow circulating water pumps were summarized, which may serve as a reference for safe, reliable and stable operation of similar units.
  • Analysis on Properties of Domestic S30432 Steel Tubes after Longterm Services
    Yang Shouen, Yang Huachun
    2015, 29(1): 56.
    Abstract ( )   Knowledge map   Save
    By means of mechanical property test, hightemperature creep rupture test, metallographic examination, scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) analysis, the microstructure, mechanical properties and corrosion resistance of domestic S30432 steel tubes with shotpeened inner surface and 17×104 service hours were investigated for hightemperature superheater, screen type superheater and reheater of a 1 000 MW ultra supercritical boiler unit. Results show that the steel tubes have the structure and properties fully meeting the requirements of relevant standards, i.e. the inner surface still has excellent steam oxidation resistance.
  • Study on Curvature Correction of Gas Turbine Rod Fastening Rotors
    Zhu Yongxiang, Leng Jinming, Tang Shidong
    2015, 29(1): 61.
    Abstract ( )   Knowledge map   Save
    An introduction is being presented to the assembly precision of gas turbine rod fastening rotors, together with a description on the testing and analysis method of rotor runout, and a discussion on treatment measures for possible rotor curvatures, to which a series of correction measures are put forward.
  • Cause Analysis on Economizer Tube Leakage in a Waste Incineration Boiler
    Huang Weihao, Zhou Qiang, Tang Songqing
    2015, 29(1): 65.
    Abstract ( )   Knowledge map   Save
    To solve the problem of economizer tube cracking and leakage occurring in a waste incineration boiler after 3 years of operation, a detail physicalchemical analysis was conducted to the economizer tube. Results show that the economizer tube cracking and leakage is mainly caused by lowtemperature S corrosion and hightemperature molten salt corrosion, and simultaneously, the poor quality of tube is one of the reasons, which accelerates the corrosion progress.
  • Commissioning of the SCR Denitration System in a Coalfired Boiler
    Wang Bosen, Li Yun
    2015, 29(1): 69.
    Abstract ( )   Knowledge map   Save
    An introduction is being presented to the general SCR denitrification process and denitrification design scheme of a certain power plant, together with a description to the key points to be noticed in different stages of commissioning, with focus on the commissioning guideline and process of SCR ammonia injection distribution. Moreover, an analysis was carried out to the commissioning effect according to the measured NO data at reactor outlet, based on which corresponding suggestions are put forward for field commissioning of the denitrification system.
  • Review and Discussion on Parabolic Trough Solar Power Systems
    Xu Wei, Yang Fan, Liu Jingjing, Miao Chenyang
    2015, 29(1): 74.
    Abstract ( )   Knowledge map   Save
    An introduction is being presented to the solar power generation technology, together with a description to the fundamental principle and structure of parabolic trough solar power systems, and with a review on development history and current research situation of the parabolic trough solar power generation technology. Main problems concerning future development of the parabolic trough solar power generation technology are discussed, to which corresponding countermeasures are proposed.
  • Special Requirements for Marine Power Equipment
    Liu Yu
    2015, 29(1): 79.
    Abstract ( )   Knowledge map   Save
    An introduction is being presented to the structure design, material selection and operation & maintenance of marine power equipment, together with some countermeasures proposed for preventing the equipment from being damaged by cavitation, electric corrosion and marine microorganism adhesion, etc., which may serve as a reference for further research and development of marine power equipment.