真空珠光砂和真空岩棉绝热性能研究

实验测定了珠光砂（６０目～８０目）和岩棉两种材料在不同压力、不同温度和不同厚度下的表观导热系数．采用双热流模型给出数值求解结果,并采用渐近拟合的方法求得了预测表观导热系数的半经验公式．     

常温用无公害隔热材料——真空粉末隔热技术

对真空粉末隔热研究的背景与进展，以及作者的一些成果做了综述，对此项技术用于常温领域必须解决的几个问题进行了分析。     

研制和开发真空绝热材料的可行性

通过真空绝热结构隔热效果的理论分析，阐述了研制和开发真空绝热材料的可行性和必要性。     

研制和开发真空绝热材料的可行性

通过真空绝热结构隔热效果的理论分析，阐述了研制和开发真空绝热材料的可行性和必要性。     

基于LabVIEW的薄质隔热涂料导热系数测试系统

为了研究薄质隔热涂料的隔热性能,在LabVIEW环境下,构建了薄质隔热涂料导热系数测试系统.描述了基于虚拟仪器的导热系数测量系统的控制方法,该仪器通过MCU89C2051实现温度控制.由DS18B20智能温度传感器适时检测、采用虚拟仪器技术在线分析、求出被测试材料的导热系数,给出了用虚拟仪器测试材料导热系数的软件设计方法及控制流程.     

大空间火下膨胀型防火涂层隔热性能试验研究

摘 要：对应3种不同类型的大空间建筑火灾场景,选取3种典型升温条件进行了36个试件的隔热性能试验。根据试验测量结果计算膨胀型钢结构防火涂层的等效导热系数。结合热重分析试验结果考察升温速率对涂层隔热性能的影响。结果表明：不同类型大空间建筑发生火灾时火场的最高温度及升温速率不同,导致涂层的膨胀倍率及炭化层泡孔结构不同,最终表现为涂层隔热性能的差异。在本文所考察范围内,升温速率越快,火场温度越高,涂层的反应越充分,隔热性能越好。不同升温条件下涂层等效导热系数代表值淰椀渀萀v大差异为48.8%。此外,膨胀型钢结构防火涂层等效导热系数随升温条件的变化程度受涂层厚度的影响,薄涂层对升温条件的变化敏感,厚涂层对升温条件的变化表现出“惰性”。     

民居建筑钢化真空玻璃的热工性能研究

针对民居建筑普通玻璃耗能高的问题,提出以钢化真空玻璃取代普通玻璃,从而实现降低建筑能耗。采用实验室测试和数值模拟的研究方法,测试计算新型钢化真空玻璃的导热系数,对比分析不同类型玻璃在不同热工分区的民居建筑能耗。结果表明：钢化真空玻璃的导热性能远小于单片玻璃、中空玻璃和三层夹胶玻璃等建筑常用玻璃的;与民居建筑采用单片玻璃的能耗相比,钢化真空玻璃的节能效率最佳,是其他类型玻璃全年节能率的2～3倍;随着民居建筑所处热工分区纬度增大,热负荷逐渐增大,冷负荷不断减小;无论在哪个热工分区,采用钢化真空玻璃民居建筑的冷/热负荷都小于其他类型玻璃的。民居建筑采用钢化真空玻璃节能效果显著,对民居建筑的绿色发展和国家“双碳”目标实现具有积极的现实意义。     

粉煤灰陶砂次轻混凝土的制备与性能

用碎石、粉煤灰陶砂和河砂作为混合集料配制不同细集料组成的次轻混凝土试样,研究它们的力学性能和热学性能。与普通混凝土相比,掺入少量粉煤灰陶砂（陶砂体积分数为25%）的次轻混凝土抗压强度得到提高,表现出较为理想的轻质高强特性。上述现象归功于混合细集料中大小颗粒搭配较好,陶砂的微泵内养护效应以及陶砂表面具有潜在活性物质参加火山灰反应,强化了陶砂与水泥石的界面强度,使掺入体积分数为25%陶砂的次轻混凝土在各龄期具有最高的强度。与普通混凝土相比,当次轻混凝土中陶砂体积分数为25%时,其导热系数可降低42%,即掺入适量陶砂可明显提高混凝土的保温隔热性能。     

玻化微珠对页岩陶砂水泥砂浆性能的影响

在陶砂水泥砂浆中使用玻化微珠等体积取代陶砂,取代率从0%～100%,研究其对砂浆的工作性能、力学性能、耐久性能和保温性能的影响。实验结果表明:当取代率小于50%时,玻化微珠可以降低砂浆的分层度和提高砂浆的抗压强度,但是会增加砂浆的密度和导热系数;而砂浆的稠度、黏结强度和线收缩率随着玻化微珠取代率的增加而增加。     

云母钛珠光颜料光泽性能影响因素的研究

对云母钛珠光颜料光泽性能的影响因素进行了研究．综合碱性中和法和缓冲法的优点，优化了云母钛珠光颜料的制备工艺，并分别以尿素和氢氧化钠作为pH值稳定剂进行实验．实验结果表明：制备云母钛珠光颜料的最佳条件为尿素作反应体系的pH值稳定剂、反应温度80℃、钛液质量分数1．5％、pH值≈3、搅拌速度400r/min．在上述条件下制备的云母钛珠光颜料，其珠光光泽相对较好．     

Test research on IR radiation characteristics control of space target using cryogenic vacuum multilayer insulation film structure

In order to achieve the objective of controlling IR radiation characteristics of space target,we design multilayer insulation film structure to cover the target.In space environment the structure comes to cryogenic vacuum multilayer insulation film structure.It can quickly lower the surface temperature of space target,approaching to the ultra-low temperature of the space environment.A vacuum simulation verification test was designed and performed.Through the analysis of test results,we can see that the surface temperature of space target covered by the structure changes with the ambient temperature,having no direct relationship with internal temperature of the target.Therefore,the designed cryogenic vacuum multilayer insulation film structure has excellent IR radiation control performance.It can reduce the target’s IR radiation intensity so as to reduce the probability of detection by IR detectors.     

Theoretical determination of thermal diffusivity of composite material

A very simple model based on the Quadrupole method was used in the theoretical analysis of thermal diffusivity of composite materials of Cu-PVC, PVC-Cu-PVC, and Cu-PVC-Cu. The use of MATLAB software with a return to real space using the Stehfest algorithm makes the time of calculation very short. The thermal responses on the rear face of each considered sample, which determine the thermal diffusivity were represented. A mathematical demonstration which confirmed the results was given. Thermal diffusivity determined from the rear face thermal responses were compared with the results of the thermal diffusivity calculated by considering the composite materials to be homogeneous, and a discussion on the two kinds of results was provided.     

A new method of rapid quality detection of vacuum insulation panels

A new method of measuring gas pressure in vacuum insulation panels(VIPs)is reported in this study,which provides a fast and efficient quality control option of production.Although there are different methods of measuring gas pressure for VIPs,connecting an internal measurement gauge to external data acquisition units is problematic.The thin high barrier film covering the panel’s core usually prevents external electrical wires or mechanical devices being connected to the inside of the VIPs.To solve this problem,a micro capacitive pressure sensor with 0 to 250 Pa detection range is developed to detect the vacuum pressure.The sensor has high linearity and a sensitivity of 10 mV/Pa.Moreover,through the communication mode study,an ultrasound communications system for VIPs is designed.It shows from operation that this system is stable and reliable,and quick for communication speed.This new method enables the quality detection of VIPs to be completed within 1 second.The minimum detectable pressure of VIPs is below 1 Pa,and the measurement error can be controlled around 5%.     

不同保温形式墙体温度场数值模拟与分析

基于有限差分方法,建立了考虑太阳辐射和环境温度变化的建筑外墙实时温度场数值计算模型.利用该模型,计算了北京地区典型内外保温墙体的温度场.计算结果表明,建筑外墙温度分布受太阳辐射影响显著,影响程度与季节、朝向密切相关.墙体保温后外表面温度升高明显;保温层内温度变化剧烈,其中外保温比内保温保温层温度变化幅度更大.外保温墙体结构层温度均在零度以上,而内保温墙体结构层温度有时处于零度以下且承受正负循环.外保温墙体外防护层一年四季温度变化明显,年温度变化可达67℃.     

磷石膏保温砂浆的制备

为实现工业废渣磷石膏的再利用,将其预处理、煅烧(蒸压)制得建筑（高强）石膏,然后与水泥、硅灰一起作为胶凝材料,配合玻化微珠轻质骨料制备半水石膏基无机保温砂浆;以生石灰作为碱性激发剂,通过单因素实验,比较分析磷石膏含量、硅灰含量、骨胶比以及磷石膏处理工艺对砂浆抗压强度、导热系数、吸声等性能的影响.结果表明:经处理过的磷石膏（半水石膏）可直接作为胶凝材料使用,配制的保温砂浆最佳配合比（质量比）为磷石膏/水泥=0.80,骨胶质量比为1∶1,硅灰占胶凝材料总量的20%;砂浆的导热系数≤0.054 W/(m·k),干表面密度≤0.35 g/cm3,抗压强度＞0.3 MPa,达到了国家标准保温砂浆性能要求.     

多孔材料有效导热系数的试验研究

本文根据多孔材料的传热特点,修正了气孔内辐射的传热计算,发展了辐射当量导热系数的新概念,建立了多孔材料有效导热系数的数学模型,推导出计算多孔材料有效导热系数的计算式。试验结果和有关文献的试验结果均证明:该模型更加符合多孔材料的实际情况,计算精度更高。     

ZnS靶材热学和力学性能测试研究

介绍了用激光脉冲法对热压ZnS(硫化锌)靶材的比热容、热导率测试和ZnS靶材线膨胀系数、抗弯强度测试方法的研究．试验证明：热压ZnS靶材有较好的热导率,在CD-RW(可读写光盘)的上下介电层应用上为记录层提供了很好的散热效果;ZnS靶材的线膨胀系数较低,有很好的尺寸稳定性;ZnS靶材有一定抗弯强度。     

Mechanism of low thermal conductivity of xonotlite-silica aerogel nanoporous super insulation material

In an effort to incorporate the low thermal conductivity of the silica aerogel and the superior structure strength of the xonotlite,a composite material of these two was produced. It was synthesized under vacuum condition and dried by supercritical drying technique. The thermal conductivity of the new material,which is at 298K with the gas pressure ranging from 1.01×10^5 to 1×10^-2 Pa,was measured using the transient hot-strip method. The mechanism of the low thermal conductivity was studied. The results indicate that the low thermal conductivity mainly results from the significant decrease of gaseous thermal conductivity of the new material due to the restriction of the motion of gas molecules in its fine structures. The formation of the fine structures is because the new material takes the pore structure of the silica aerogel which consists of mainly nanometer-sized pores.