瞬态热流法导温系数测试装置与软件开发

介绍了基于瞬态热流法的导温系数快速测定系统,针对测试装置开发了专门的数据采集、处理和控制软件,该软件可以进行过程监控,高频采集数据并进行误差分析处理.用该装置测试了几种固体散状物料的导温系数,测试结果表明该系统稳定性高,误差小,有一定的工业应用价值.     

基于MIMU/GPS组合导航系统的应用研究

根据车载导航系统发展现状,提出了一种基于GPS和MIMU技术的低成本的、可用于市场推广的组合导航系统方案。采用MIMU与GPS松散组合方式,以速度和位置作为观测量设计了Kalman滤波器。该方案以ARM9作为中央处理器,详细介绍了系统的设计与实现。经测试,该系统与传统GPS相比,具有更高的稳定性和更精确的导航精度。     

煤层自燃隐蔽火源红外成像探测技术研究

利用红外成像技术对煤矿井下隐蔽高温区域探测是一个崭新而富有挑战的课题。课题以煤的热传导理论为基础,结合红外辐射测温理论、红外热像仪测温原理,以红外热像观测为手段,进行实验研究,掌握了松散煤体存在内热源时煤热量传递过程、松散煤体表面红外辐射特征,建立了松散煤体有源数学模型,通过数值模拟,研究了导热系数、辐射率对煤体红外辐射能量的影响。     

用．NET开发导温系数测试装置的测控与仿真软件

采用瞬态热流法测定导温系数的方法具有装置结构简单、测试时间短和误差小等优点。但由于需要在线采集数据,因此必须开发专门的软件。经过分析对比,采用．NET技术开发本系统软件具有较好的优越性。该软件基于控件与类库的设计,实现了实时数据通信、数据采集、数据存储、图形显示、数据处理、实验仿真、数据输出等功能。系统的运行结果表明,该系统稳定性高、误差小、操作方便,有一定的应用价值。     

多煤体光纤工业控制网中混合环路控制的研究与实现

介绍了用可编程逻辑器件实现多煤体光纤工业控制网中混合环路控制部分的设计及模拟,并给出了模拟及测试结果。     

星载微波探测仪软件时序表化的设计方法

基于一个实际的星载微波探测仪软件项目,介绍了软件时序表化的设计方法.采用该方法实现的软件,其运行过程就是查询时序表的过程,主要特点是软件结构简单、模块功能和结构耦合松散、运行效率高、易更改和测试.这些特点在星载微波探测仪的设计、测试和定标过程中得到了充分的验证,设计方法可为其他航天软件的研制提供参考.     

智能发动机温控电路测试系统的研制

介绍了用于某型战斗机发动机温度控制电路的智能测试系统的研制过程, 重点介绍该测试系统的软、硬件结构和设计思想。可以为其它类似测控系统的设计提供一个参考     

基于海量空间数据库的高可用性研究与应用

以某市卫星遥感图像分析系统后台的海量空间数据库为背景,以实用性和高可用性为目标,阐述系统存储架构的设计和功能实现,介绍该系统数据库优化方案的设计以及数据库备份、恢复策略的制定,并采用跨地域的Data Guard松散连接的技术实现了数据库容灾方案,同时对该系统未来的发展趋势进行了分析。     

基于PXI总线的导弹测试系统设计

为了满足某型导弹的批生产测试需求,设计了基于PXI总线的导弹测试系统;介绍了该测试系统的系统组成、工作原理,详细阐述了硬件系统和软件系统的设计方法和思路;该测试系统使用PXI总线,综合RS422、ARINC429等多种通讯模块,采用标准化、模块化设计方法;能够完成导弹的功能和性能测试,测试内容全面,测试结果正确可靠;经过实践证明,该测试系统可实现导弹的全时序自动化测试,工作稳定、可靠性高,能够很好地满足某型导弹的测试需求.     

基于EPM7128的多功能测试系统的研制

设计了一种多功能参数测试系统,介绍了其工作原理及软件与硬件设计。该测试系统与上位机配合可测试某一专用产品的运行参数,并可实时给出所测参数,且可按需要的格式保存、显示或打印数据,有利于数据的科学管理。该测试系统为生产和使用该产品的单位提供了一种行之有效的测试与维护工具。     

Measurement technique for the thermal properties of thin-film diaphragms embedded in calorimetric flow sensors

In diaphragm-based micromachined calorimetric flow sensors, convective heat transfer through the test fluid competes with the spurious heat shunt induced by the thin-film diaphragm where heating and temperature sensing elements are embedded. Consequently, accurate knowledge of thermal conductivity, thermal diffusivity, and emissivity of the diaphragm is mandatory for design, simulation, optimization, and characterization of such devices. However, these parameters can differ considerably from those stated for bulk material and they typically depend on the production process. We developed a novel technique to extract the thermal thin-film properties directly from measurements carried out on calorimetric flow sensors. Here, the heat transfer frequency response from the heater to the spatially separated temperature sensors is measured and compared to a theoretically obtained relationship arising from an extensive two-dimensional analytical model. The model covers the heat generation by the resistive heater, the heat conduction within the diaphragm, the radiation loss at the diaphragm’s surface, and the heat sink caused by the supporting silicon frame. This contribution summarizes the analytical heat transfer analysis in the microstructure and its verification by a computer numerical model, the measurement setup, and the associated thermal parameter extraction procedure. Furthermore, we report on measurement results for the thermal conductivity, thermal diffusivity, and effective emissivity obtained from calorimetric flow sensor specimens featuring dielectric thin-film diaphragms made of plasma enhanced chemical vapor deposition silicon nitride.     

Application of the laser flash diffusivity method to thin high thermal conductivity materials

The evolution of semiconductor devices and the dramatic increases in the power dissipation per unit volume of ever smaller microelectronic devices means electronic packaging technologies must evolve to manage the dissipation of heat. One of the major issues is the development of new packaging materials optimised for heat management. Future packaging will incorporate layers with thermal diffusivities exceeding that of copper in thin, sub-millimetre foils. Metrology techniques are needed to measure the thermal diffusivity of these thin, thermally fast materials. As some new materials are developed only in the form of thin substrates the laser flash technique is limited in its application to these materials. This paper addresses the application of a nanosecond pulsed laser flash instrument to the measurement of thermal diffusivity of thin high thermal conductivity materials and the errors associated with the measurement. An experimental comparison is made with a laser flash instrument where the laser pulse is of higher energy but millisecond pulse duration. Received: 25 October 1997/Accepted: 2 January 1998     

热导传感器的信噪比改善方法研究

针对如何改善热导传感器的信噪比问题,以煤中氮元素的测试为载体,研究了采用热导传感器在测量煤中含氮百分比过程中改善测量精度的方法。对测量中存在的问题：热导池的不稳定性、温度对试验结果的影响、电源稳定性的影响以及滤波电路的选频特性对对试验结果的影响等进行了原因分析,并逐个进行了相应的方法优化和设计改进,最后通过对测氮系统的输出信号进行对比,结果显示信噪比有较大提高。     

土壤源热泵中土壤导热系数测定系统设计

土壤导热系数是土壤源热泵中地下埋管换热器设计的重要参数,其大小对钻孔深度与个数有显著影响;针对土壤导热系数的测定对土壤源热泵系统设计的重要性,利用电加热法研制了土壤导热系数测定系统;系统的控制部分基于先进的LonWorks现场总线技术,并结合DDE标准与Visual Basic数据库开发技术构建;整个系统包括控制器的软硬件设计以及上位机监控软件设计;系统根据实验条件对输入功率进行了精确地控制,实验获得的数据满足进行土壤导热系数计算的需要。     

火电厂中储式燃煤炉煤粉仓粉位 实时监测系统的研究

本文针对火电厂燃煤炉煤粉仓粉位测量的现状及存在的问题 ,提出了一种分段电容、连续正交排列 ,总线驱动的测量理论 ,并据此研制了高精度 ,高可靠性 ,高性价比的粉位实时监测系统 ,经国内 6 0多家火力发电厂的实际应用证明 ,这是一项有生命力的创新 ,值得在火电厂普遍推广应用。     

真空热试验温度参考点热响应测试系统设计与实现

在航天器真空热试验的温度测量中应用最广泛的是热电偶测温系统,温度参考点是热电偶测温系统的重要组成部分,对温度测试数据的准确性和航天器产品的安全有很大影响。为了在热试验开机前对参考点铂电阻与热点偶补偿端匹配关系的正确性进行验证,设计了一种可用于真空热试验的热电偶测温参考点热响应测试系统。该系统由加热器以及控制箱组成,可通过LAN网络与上位控制计算机连接实现热响应远程测试。文章通过对参考点装置的热分析以及热响应测试原理分析,给出了系统的硬件结构以及软件设计方案,并在多项航天器真空热试验中投入使用,提高了航天器真空热试验热电偶测温系统的可靠性。     

热强度试验中热电偶调理模块的设计与应用

热强度试验现场环境复杂,会对热电偶、热流等微弱电压信号产生较大电磁干扰,影响测量精度甚至控制信号精度。本文描述了热电偶调理模块的设计,对小信号进行隔离放大,有效抑制热强度试验存在的干扰,提高了系统的精度。     

INV-WATFLX,a code for simultaneous estimation of soil properties and planar vector water flux from fully or partly functioning needles of a penta-needle heat-pulse probe

Soil thermal properties and water fluxes are fundamental for understanding water and heat transport phenomena in the vadose zone. Processes of interest include quantifying infiltration and runoff in addition to solute transport rates, which are of great interest in many scientific and engineering applications where water flux and temperature are key parameters. In this study, INV-WATFLX was developed for simultaneously fitting thermal diffusivity, thermal conductivity and heat velocities in a plane normal to a penta-needle heat-pulse probe (PHPP) using temperature rise measurements in a porous medium. The inverse problem is formulated as the minimization of a generalized least-squares criterion by means of a Gauss–Newton–Levenberg–Marquardt method. Fitted temperature measurements following a heat-pulse injection were calculated from an analytical solution of temperature rise derived at the four thermistor positions of the PHPP. The INV-WATFLX code was tested with a set of synthetic simulations using CORE^2D V4. Relative errors of thermal diffusivity, conductivity, bulk volume heat capacity, and water fluxes estimated in INV-WATFLX to their prescribed values in the synthetic simulations were smaller than 3%. We also evaluated the ability of INV-WATFLX to provide estimation of thermal properties and fluxes from temperature rise measured by a sub-set of the four thermistors. INV-WAFLX was applied to laboratory column flow experiments for water flux estimation using a PHPP. Water fluxes estimated using INV-WATFLX was comparable to independently measured fluxes. The new code provides reliable estimation of soil thermal properties and water fluxes from temperature rise using heat-pulse measurements.     

Contactless thermal characterization of high temperature test chamber

In this paper the methodology and the results of a contactless thermal characterization of a high temperature test chamber will be introduced. The test chamber is used for fatigue testing of different MEMS devices where the homogenous temperature distribution within the close proximity from the heating filaments is very important. Our aim was to characterize the evolving temperature distribution inside the test chamber. In order to achieve smaller time constant a new contactless sensor card was developed. The contactless thermal characterization method introduced in this paper enables in situ heat distribution measurement inside the test chamber during operation, with the detection of potentially uneven heat distribution.