发动机性能台架试验自动化系统的开发

开发了发动机性能台架试验自动化系统,包括发动机台架标定和性能开发试验自动化运行系统、发动机台架试验实时控制系统、发动机试验保护策略和系统、发动机台架试验测量系统不确定度评定、试验台架传动系统扭转振动校核等。将自动化系统应用于试验项目,实现了发动机台架标定和性能开发试验的完全自动化,提升了试验效率和质量,加快项目开发进度。     

溪洛渡水电站福伊特水轮机模型及验收试验

为了检验溪洛渡水电站福伊特水轮机模型的水力特性,进行了水轮机模型验收试验,包括效率试验、出力试验、空化试验、压力脉动试验、飞逸试验、轴向水推力试验、导叶水力矩试验、筒阀下拉力试验、蜗壳差压试验、尺寸检查等试验内容.试验结果表明溪洛渡电站福伊特水轮机模型具有良好的重复性,模型水轮机的各项水力性能指标均满足合同要求,模型的...     

ICP-AES法测定钛合金中合金元素含量

本文采用电感耦合等离子体发射光谱仪对钛合金中硅、铁、铝、钼的分析方法进行了试验研究 ,着重研究了内标试验、离峰校正试验及第三元素干扰试验 ,通过试验找到了一个分析钛合金的准确可靠的方法 ,本方法灵敏度及准确度高 ,操作简便、快速。     

大功率船用柴油机试验数据管理系统初探

从柴油机试验数据管理需求入手,分析了现行数据管理的不足,介绍了试验数据管理系统在数据管理、流程管理方面的优势,具体探讨了试验数据管理系统的架构、功能以及组成,试验数据管理系统的建立可为柴油机试验及研发提供有力的保障。     

600MW锅炉燃烧调整试验研究

为了解决广东某电厂600 MW锅炉NO_x排放量过高、炉膛出口烟气温度偏差较大、锅炉氧量控制不经济等问题,通过总风量试验、主燃烧器外二次风旋流强度调整试验、一次风速调整试验、燃尽风总量调整试验、煤粉细度调整试验、燃尽风燃烧器旋流强度调整试验、最佳运行方式调整试验等系统的锅炉调整方式,对锅炉进行燃烧调整试验。调整结果给出了不同负荷下锅炉的最佳运行方式,解决了锅炉面临的各种问题,达到了预想的效果。     

大功率牵引交流传动系统试验平台搭建

介绍了大功率牵引交流传动系统地面试验系统的功能原理、系统构成和技术特点,完成了大功率交流传动系统的联调试验和牵引变流器、牵引电机、功率模块等关键部件的部分型式试验.试验验证和应用情况表明,该试验台满足了大功率交流传动系统的试验需求.     

M701F型燃气轮机SFC系统试验浅析与探讨

SFC系统有两个重要试验,一个是测速探头调整试验,另一个是SFC性能试验。本文以测速探头调整试验为例,对试验目的和意义、试验原理进行了说明,对试验项目及调整方法进行了阐述并提出了试验中应注意的事项,同时对SFC性能试验做了简单概述,供同行参考和探讨。     

汽车发动机ECU的可靠性试验研究

针对国内某型汽车发动机电子控制单元(ECU)自主研发关键技术,开展了ECU可靠性试验研究.根据相关可靠性试验标准及汽车发动机ECU的具体特性,研究了ECU可靠性筛选试验、可靠性增长试验和可靠性鉴定试验的试验原理和实施流程,开发了ECU可靠性试验系统,并制订出详细的ECU可靠性联合试验方案.在此基础上,对国内某型汽车发动机ECU进行了现场试验.试验结果表明:试验系统平台设计合理,试验方案可行,经过试验的ECU样品,其平均寿命MTTF得到较大幅度增长,可靠性水平得到显著提高.     

核电工程试验的过程控制

遵从核电质量保证对工程研究开发的规定,以及基于核电工程试验的实施过程具有质量保证中规定的"特殊过程"的基本特征,提出了核电工程试验成功的标志与主要准则.从试验目标和质量保证2个角度,明确了核电工程试验各个阶段的控制要素和进行验证的要求.对试验设施可用性验证是试验过程控制的最重要环节,正式试验之前必须验证和确认试验模型特征量正确、关键参数测量准确、工况保障条件可控、质/能平衡测定合格和典型工况试验结果合理,以确保试验数据有足够的置信度.在国家大型先进压水堆核电站重大专项关键试验项目中,已全面实施了这种过程控制的相关程序,有效地促进了试验成功.     

缩短6110柴油机出厂试验时间的研究

介绍了无锡柴油机厂通过对传统产品6110柴油机的出厂试验进行研究,选择磨合油,同时科学制订磨合规范,并将新旧出厂试验用油及磨合规范进行对比试验研究,最终确立了行之有效的、明显缩短了出厂试验时间的试验程序及试验用油,提高了工作效率及经济效益,且满足了工厂产能扩大的需要.     

Heat transfer performance of a double-loop separate-type heat pipe: Measurement results

An experimental study is presented for the heat transfer performance of a rectangular double-loop natural circulation system, in which the condensers are made of double tubes with water-steam as the working fluid. Detailed temperature measurements of the core fluid and the wall are made, from which overall heat transfer coefficients for the evaporator, condensers, and entire system are obtained. Parametric studies of the liquid charge level, fluid properties, and heating or cooling conditions on the heat transfer performance are presented and correlation equations are given. The results show that the overall heat transfer coefficients for the evaporator, condensers, and entire loop are all increasing with decreasing liquid charge level. Overhead phenomena at low liquid charge level and thermal oscillation at some situations are also observed and discussed.     

不同加热方式下环路热管蒸发器可视化研究

针对环路热管内部工质相变及流动换热问题,设计了环路热管蒸发器中心通道可视化实验平台,研究了不同加热方式对热管内工质状态和传热特性的影响。结果表明：加热方式直接影响热管10W启动过程,双面加热启动速度最快。相同热载荷时,不同加热方式下环路热管热阻及蒸发器中心通道内液面高度和成核情况存在差异。10W - 40W热载荷时,随着热载荷的增大,三种加热方式的传热热阻均在减小。40W-50W热载荷时,顶部加热方式下的热管性能出现恶化,底部加热传热性能出现停滞,仅双面加热性能稳定并有提高趋势。随着热负荷的增加,蒸发器中心通道内气液界面升高、气泡的产生变得更加剧烈,蒸发器通过吸液芯向储液器的漏热量增加,进而影响环路热管的性能。     

重力热管单线内螺纹分布强化换热实验研究

采用实验方法,研究了不同的内螺纹分布和油浴温度等因素对热管换热特性的影响。实验选用的热管材料为紫铜,外径16 mm,壁厚3 mm,长度为200 mm,传热工质为水,充液率为20%。实验结果表明:在同一油浴温度下,内螺纹重力管的启动特性要优于光滑重力热管。对比不同油浴温度下,布置内螺纹能够有效地降低热管的工作温度。实验选型的内螺纹仅布置在蒸发段不会提高热管的换热系数,而在绝热段和冷凝段布置内螺纹则能够使换热系数显著提升,且随油浴温度的增加,换热系数线性增加。     

Evaporation Heat Transfer Coefficient in a Capillary Pumped Loop and Loop Heat Pipe for Different Working Fluids

Capillary pumped loop (CPL) and loop heat pipe (LHP) are passive two-phase heat transport devices. They have been gaining importance as a part of the thermal control system of spacecraft. The evaporation heat transfer coefficient at the tooth–wick interface of an LHP or CPL has a significant impact on the evaporator temperature. It is also the main parameter in sizing of a CPL or LHP. Experimentally determined evaporation heat transfer coefficients from a three-port CPL with tubular axially grooved (TAG) evaporator and a TAG LHP with acetone, R-134A, and ammonia as working fluids are presented in this paper. The influences of working fluid, hydrodynamic blocks in the core, evaporator configuration (LHP or CPL), and adverse elevation (evaporator above condenser) on the heat transfer coefficient are presented.     

Thermal Performance of a Closed-Loop Pulsating Heat Pipe With Multiple Heat Sources

A closed-loop pulsating heat pipe with multiple heat sources (CLPHP w/MHS) was invented to be used as a heat transfer medium between a number of heat sources to a single heat sink. However, an issue on the suitable heat source arrangement that causes the heat pipe to have the highest thermal performance was suspicious. The CLPHP w/MHS was made of a copper capillary tube with 32 turns. There were three heat sources with nonidentical input heat flux installed along a longitudinal axis in the evaporator section. Experimental investigations were conducted by permuting the heat sources into six unduplicated arrangements. For the vertical CLPHPs, the highest thermal performance is achieved when heat sources are arranged in consecutive order ascending from the lowest heat flux at the inlet of the evaporator section, since working fluid is promoted to circulate in complete one direction and then the heat can transfer more continuously. Finally, for the horizontal CLPHPs, the highest thermal performance is achieved when the heat sources are arranged in opposite order to the case of vertical CLPHPs, that is, descending from the highest heat flux, since working fluid pulsates with no intermission stop and this causes the heat transfer to be not interrupted.     

海上油气平台余热朗肯循环发电系统热力学分析

海上油气平台存在大量的燃气轮机余热。通过建立海上平台余热朗肯循环发电系统仿真模型,开展平台余热发电热力学及热经济性分析。选取工质泵功率、发电机输出功率、系统热效率、换热面积和单位面积发电量等参数作为优化目标,研究不同冷凝温度下优化目标函数随蒸发器烟气进出口温差的变化规律。结果表明:随着蒸发器烟气进出口温差的增加,工质泵功率、发电机输出功率和系统APR先增大后减小。冷凝温度越高,工质泵功率越大,发电机输出功率和系统热效率越小。当冷凝温度为65℃时,系统APR最大。受透平出口蒸汽干度的限制,所研究工况下,系统发电机最大输出功率为7 496 kW,系统最大热效率和APR分别为14.16%和5 kW·m~(-2)。研究结果可为撬装化、集成化海上油气平台余热发电系统研制提供理论参考。     

Heat Transfer in a Loop Heat Pipe using Diamond-H2O Nanofluid

The main aim of this study is to enhance the thermal performance of loop heat pipe (LHP) charged with nanofluid as the working fluid. Thus, experiments are conducted to investigate heat transfer characteristics of using diamond-H₂O nanofluid with nanoparticle mass concentration ranged from 0% to 3% in a LHP as a working medium for heat input range from 20 W to 60 W. The three-dimensional model, laminar flow and heat transfer governing equations are solved using the finite volume method. The simulations are carried out with three-dimensional model based on the characterization of the working fluid inside the LHP to give an insight into the heat transfer and fluid flow mechanism. The LHP performance is evaluated in terms of temperature distributions and total thermal resistance of LHP. It is inferred that the temperatures obtained at all points in evaporator side of LHP charged with diamond-H₂O nanofluid are lower and reach their steady state faster than LHP charged with pure water. At the constant heat input, test results showed the average decrease of 5.7%?10.8% at nanoparticle mass concentrations ranging from 0.5% to 3% in R_th of LHP as compared with pure water (0%).     

低温环路热管综述

环路热管是以多孔毛细芯抽吸力为动力的相变传热设备,可根据实际应用改变结构形式,能在远距离传热的同时保持良好的均温性,并且可在微重力环境下运行。环路热管工作温区较广,按照其工作温区一般可分为高温环路热管(350 K以上)、常温环路热管(200～350 K)和低温环路热管(200 K以下)。为了满足深空探测的需要,低温环路热管广泛应用于航天设备温控系统中并表现出优异的性能。按照孔隙特征和结构形式将用于环路热管的毛细芯分为四种,简要阐述每种毛细芯制备和特点;综合分析了近年来低温环路热管技术主要理论和实验研究成果,将目前低温环路热管常见的工作温区分成五个部分,分析影响低温环路热管传热性能的因素,包括工质充装量、反重力高度、次蒸发器功率等。最后,提出优化措施以满足未来深空以及地面应用的需求。     

结构参数对电厂翅片管散热器动态特性的影响

散热器经常处于变化的工作条件中,研究散热器的动态特性有助于改善间接空冷系统的安全和经济运行,而散热器的结构参数会影响其动态特性。根据能量守恒建立了散热器空气、管壁和循环水的热平衡偏微分方程,采用改进欧拉法对偏微分方程组进行求解。以迎面风速阶跃变化为典型工况,研究了换热面积、换热系数和工质体积对散热器动态特性的影响。结果如下:当空气侧换热面积增加时,散热器换热量增大,两个稳态之间的空气出口温度差值不变,循环水出口温度差值增加,空气侧响应时间增加,循环水侧响应时间不变。当循环水侧换热面积增加时,散热器换热量增大,两个稳态之间的空气和循环水出口温度差值不变,空气侧和循环水侧的响应时间也不变。换热系数变化时,散热器动态过程的变化规律与换热面积变化时类似。空气侧工质体积变化对散热器动态特性没有影响。循环水侧工质体积增大会使得动态响应时间变长。     

Effect of Operating Parameters on the Heat Transfer and Liquid Film Thickness of Revolving Heat Pipe

This paper presents a study on the effects of operating parameters on the liquid film thickness and heat transfer of revolving heat pipe. The effects of speed, radius of rotation, evaporator and condenser temperatures, and mass of the working fluid are considered. Also, the effects of these parameters on the maximum heat transfer and minimum mass of the working fluid supplied to the heat pipe are considered. A simplified theoretical model is presented to estimate the heat transfer and the liquid film thickness. The theoretical model is used to determine the driven forces on the control volume. The system of equations associated with the heat pipe model is solved using the fourth-order Runge–Kutta method through a numerical code written in MATLAB. The results show that the heat transfer increases by decreasing the mass of the working fluid and increasing the temperature difference through the heat pipe. They also show that the liquid film thickness increases with the decrease in temperature difference and with increase in the mass of fluid. The maximum heat transfer increases with the increase in the rotation speed. The minimum mass of the working fluid supplied to the heat pipe increases with the increase in temperature difference and with the decrease in the rotation speed.