烟气脱硫装置的腐蚀与防护

湿法烟气脱硫装置因其处理烟气量大、脱硫率高、运行周期长、运营成本适中，已成为国内外火电厂烟气脱硫的主导装置。但该装置腐蚀环境苛刻、防腐蚀工程量大、装置腐蚀维修困难。本文针对湿法烟气脱硫装置的各区域不同的腐蚀环境特点，提出了防腐蚀复合衬里结构体系，为我国大型火电厂烟气脱硫装置的防腐蚀技术国产化提供了可靠的技术信息。     

以除氧水为介质的低压锅炉停炉湿法保护探讨

介绍了锅炉停炉腐蚀的原因、机理和常用停炉保护方法,从防腐蚀效果、经济性和安全性等角度出发,建议采用以除氧水为介质的低压锅炉停炉保护系统,可在锅炉短期停炉期间进行有效的防腐蚀控制。     

燃气轮机叶片的热腐蚀及其防止

本文根据近十几年来国内发生的燃气轮机叶片的热腐蚀现象,从理论上对此加以分析.提出叶片热腐蚀的可能原因.分析了各种重要因素对它的影响,其中特别是高温对热腐蚀的形响.以叶片热腐蚀的内部原因与外部条件为依据,推荐出一些主要的防腐蚀措施,以供燃气轮的运行与制造部门参考.     

海上风电防腐蚀研究现状与前景

近年来,海上风电技术在全世界范围内迅速发展,作为能源系统去碳化和实现零排放的关键技术之一,海上风电的地位日趋重要。我国的海上风能资源丰富,但风电机组在高盐雾、高湿度、长日照、微生物附着等苛刻的海洋环境中长期运行时,面临着严峻的腐蚀挑战。本文从风电机组组成的角度出发,综述了目前行业内对风电机组各部位的腐蚀防护研究情况,并提出了未来海上风电防腐蚀研究的展望。     

浅谈水泵机组的节能潜力

从水泵机组选型配套、安装运行、维护管理及运行调节等方面入手 ,分析了水泵机组实现经济运行的途径 ,从而达到节能的效果。     

如何做好地下煤气管道防腐

地下煤气管道腐蚀的原理、种类、防腐办法、工程管理及对节能的意义。     

YL—1型锅炉湿保剂

叙述了停用锅炉腐蚀的原因及停炉保养存在的问题，介绍了ＹＬ－１型湿保剂的试验结果和防腐蚀机理，并与硅胶，无水氯化钙比较，认为该湿保剂具有防腐蚀效果好，价廉及使用方便等特点。     

节能监测仪器设备的运行及管理探讨

节能监测仪器设备是实施节能监测工作的基本条件,对这些仪器设备的管理需要实施统一、细化、规范化的操作准则。从仪器配备、台帐记录、使用维护、量值溯源等方面探讨节能监测仪器设备的科学管理,以便更高效、更规范地开展节能监测工作,保证监测数据的准确有效。     

烟气露点温度的测量和低温腐蚀的防止

本文介绍了锅炉烟气的露点温度的概念，测试方法，测试意义，对进一步搞好锅炉的节能监测，预防和减少低温腐蚀有指导作用。     

异抗坏血酸稳定亚硫酸盐防腐蚀作用的研究

通过除氧试验,腐蚀试验和电化学试验,了异抗坏血酸对亚酸酸盐仿腐蚀效果的影响。结果表明,异抗坏血酸使亚硫酸盐几乎失去了除氧作用,但却提高了亚硫酸盐在含氧水中对２０ｇ钢的防腐蚀性能,使钢的自腐蚀电位更剧烈负移并使阴极极化增加。     

优化半导体制冷工况的理论分析

对半导体制冷的原理进行简单介绍,同时对三种不同工况下半导体制冷进行理论分析,导出使制冷量和制冷系数达到最大值时的电流值,并由此得出设计用的主要参数,给半导体制冷器的设计提供了依据。     

两级半导体制冷性能优化设计

在半导体制冷单元制冷基本公式的基础上,按照最大制冷系数的设计方法,得到了两级半导体制冷电堆中间温度的计算公式。根据建立的模型,对制冷单元的尺寸进行了优化设计,给出了级间元件个数比的最优分配,并分析了相应的影响因素。本文所得的结果对多级半导体制冷的优化设计具有一定的理论意义。     

Dynamical cooling of semiconductor by contact layer

The subject of this paper is the presentation of a simple theoretical model of cooling of a semiconductor. The problem of the unsteady behaviour both of the semiconductor and of the cold plate that are in touch by the contact layer was studied analytically. The influence of the parameters of the materials and the cooling conditions was investigated. The results in the form of an analytical formula and graphs are presented and the heat stream is compared with the experimental results.     

Simulation of the transient temperature distribution in a high-power semiconductor device cooling apparatus using heat pipes

This study describes the transient temperature distributions in a cooling apparatus for high-power semiconductor devices used in electric-railcar drive systems. The cooling apparatus is composed of heat pipes, air-cooled fin arrays, and a metal block which is used for attaching several semiconductor packages, In our numerical simulation model, we substituted solid elements for the heat pipes, and determined their thermal properties by experiment. As a result, we could obtain transient temperature distributions for the cooling apparatus through a heat conduction analysis. Calculated results showed that when the amount of heat generated in the devices changes, the temperature of the cooling apparatus changes more slowly than that of the devices. A comparison between the transient-temperature distribution calculations and the experiments confirmed the accuracy of the modeling and prediction method. Thus, these calculations can be used to provide data for packaging design, especially concerning thermal stress and fatigue in the packages. © 1998 Scripta Technica, Inc. Heat Trans Jpn Res, 26(2): 107–115, 1997     

Modelling of a pin-fin heat converter with fluid cooling for power semiconductor modules

This paper presents a way to design a finite-element computer model of cooling system with a complicated geometry. The computer model is developed on the basis of a commercial software package ABAQUS. The steady state forced-convective fluid cooling of a pin-fin heat converter for power (∼1 kW heat power) semiconductor module has been investigated on the basis of computer simulation. A phenomenological equation has been used for calculation of the local value of the heat transfer coefficient for the liquid-solid interface. The impacts of the thermal conductivity of the pin-fin sink material, volume flow rate of the cooling liquid and geometrical design of the pin-fin sink on the thermal resistance of the converter are shown. Copyright © 2003 John Wiley & Sons, Ltd.     

Electrospray cooling for microelectronics

The challenge of effectively removing high heat flux from microelectronic chips may hinder future advancements in the semiconductor industry. Spray cooling is a promising solution to dissipate high heat flux, but traditional sprays suffer from low cooling efficiency partly because of droplet rebound. Here we show that electrosprays provide highly efficient cooling by completely avoiding the droplet rebound, when the electrically charged droplets are pinned on the heated conducting surface by the electric image force. We demonstrate a cooling system consisting of microfabricated multiplexed electrosprays in the cone-jet mode generating electrically charged microdroplets that remove a heat flux of 96 W/cm² with a cooling efficiency reaching 97%. Scale-up considerations suggest that the electrospray approach is well suited for practical applications by increasing the level of multiplexing and by preserving the system compactness using microfabrication.     

The analysis of triangular cycles of cooling and heating

Theoretical study of triangular cycle with cooling and heating at variable temperatures is investigated in this study. Simple approximated correlations for COP are obtained. By implementation of the cooling and heating using multistage machines, single-compressor machines accompanying with refrigerants mixtures, semiconductor thermopiles, and the supercritical cycles with variable temperature of heat rejection, the “triangular” cycle shows promising interesting features.     

Numerical simulation of thermal runaway phenomena in silicon semiconductor devices

A mathematical model for heat production due to thermal excitation of conductive electrons and positive holes in a semiconductor pn junction is derived and discussed. The model is applied to simulate the thermal runaway phenomena in power electronics semiconductor devices. Our discussion focuses especially on the modeling of unexpected huge currents due to an excessive temperature increase. Calculated dynamics of temperature distributions of a silicon wafer while cooling performance decreases proved it is possible for a silicon wafer to be heated over its melting point in a few milliseconds. Our results indicate that if a local hot spot arises in a wafer, the thermal intrinsic excitation carries an increased diffusion current of minor carriers and a recombination current in the depletion layer of a pn junction. Also it appears to be important that cooling performance should be uniform on the wafer to avoid the growth of hot spots and thermal‐runaway itself. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(6): 438–455, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10044     

Nonlinear optimal on-line heat-dissipation control methodology in electronic devices

The essential element in obtaining semiconductor electronic device enhanced reliability involves solving the heat-dissipating issue. Certain electronic components possess varying thermal properties and the strength of the heat generated by the semiconductor chip is unknown. Therefore, the heat dissipation control problem is both complicated and perplexing. This paper proposes a methodology, the LQG/IE tracking algorithm, to solve the nonlinear heat dissipation control problem. The IE method, which is a combination of an Extended Kalman filter and Recursive Least Squares Estimator, estimates (in real time) the unknown time-varying heat source generated by the semiconductor chip using temperature measurements of the package seal surface. The LQG tracking algorithm is adopted to analyze the feedback gain to control the heat dissipation. The simulation results reveal that an effective and optimal heat dissipation controller can be implemented for the cooling system using the LQG/IE tracking algorithm.     

Thin semiconductor films for radiative cooling applications

Passive cooling systems use simple low-cost techniques to provide summer comfort in warm climates and can also be used to keep food, liquids and other materials at temperatures below ambient. Radiative cooling devices require a convective shield that should reject solar radiation but be transparent to mid-IR thermal radiation. In this paper, chemical solution deposition of thin semiconductor films (PbS and PbSe) onto polyethylene foils for radiative cooling applications is described. Optical and structural characterizations of the films were performed using UV–Vis, FTIR spectroscopies, X-ray diffraction and electron microscopy. Additionally, pigmented shields, which exhibit good radiation scattering properties, were prepared by incorporation of ZnS or ZnO into polyethylene. We also studied a combination of pigmented polyethylene foils coated with thin films of PbS that show improved optical properties for cooling purpose.