煤层气化上覆岩层温度场分布规律研究

由于温度对岩石的影响作用,高温下岩体的物理力学性能及破坏规律与常温下岩体的大不相同;通过对气化炉上覆岩层岩石导热系数试验,取得了不同温度下岩石的导热系数及规律方程,采用comsol多物理场耦合软件进行传热数值计算。研究表明：岩石的导热系数随温度增加呈下降趋势,随岩性不同下降的速度基本相同;在不同的温度下,各岩性的导热系数有一定的差异。通过模拟软件的分析得到了煤层气化上覆岩层温度分布随高度方向变化的规律,温度下降梯度随岩性不同而不同。这一结果为进一步研究煤炭地下气化上覆岩层强度变化及破坏规律提供了理论指导。     

FLUENT模拟分析巴基纸基复合材料的温度场分布

为了研究加热过程中加热功率及聚合物基体导热系数等因素对巴基纸基复合材料达到稳态所需时间及温度场分布的影响规律,采用有限元软件FLUENT分别模拟了不同工况条件下矩形弯曲、正弦形及平板形巴基纸增强聚合物基复合材料的热传导性能。计算结果表明:三种形状巴基纸基复合材料加热达到稳态后整体温度水平均随加热功率的增大呈线性增长,且巴基纸基复合材料达到稳态时所需时间也随加热功率的增大而延长。随着聚合物基体材料导热系数的增大,巴基纸基复合材料温度分布更加均匀,且巴基纸基复合材料达到稳态所需要的时间越短。分析认为,加热功率对巴基纸基复合材料温度分布规律的影响主要通过巴基纸加热片的单位体积热源起作用;聚合物基体导热系数增大利于巴基纸加热片热量的散出,因此缩短了巴基纸基复合材料达到稳态的所需时间。     

随钻电磁波电阻率测井在水平井各向异性地层响应特征研究

在砂泥岩薄互层、缝洞型地层以及泥页岩储层等非常规油气藏中,地层普遍存在各项异性。在水平井测量环境下,仪器响应方式与直井不同,同时受到地层各向异性影响,电阻率测井响应更加复杂,增加了储层评价难度。使用数值正演方法模拟了水平井各向异性地层电磁波电阻率测井响应,分析了各向异性地层对电磁波电阻率测井响应的影响规律。研究结果表明:随着各向异性系数增大,方位相位差电阻率和方位幅度比电阻率均增大,而方位幅度电阻率随各向异性系数增大分离程度比方位相位差电阻率分离程度小。最后,对电磁波电阻率实测资料进行分析。可知,各向异性地层往往会导致水平井电阻率与直井电阻率存在显著差异,同时在泥岩层会出现曲线分离现象。     

含盐冻土冻结温度及导热系数试验研究

为研究粉质黏土含盐量和初始含水率对热物理特性的影响规律,通过开展室内温度试验测得不同含盐量和含水率粉质黏土的冻结温度和导热系数,分析了不同因素对含盐粉质黏土冻结温度和导热系数的影响。结果表明：NaCl含盐粉质黏土冻结温度及过冷温度随含盐量增加均呈线性降低,而Na₂SO₄含盐粉质黏土均先降低后略增加,两种含盐粉质黏土导热系数均随含盐量的增加而减小;冻结温度及导热系数均与初始含水率成正相关关系,低于饱和含水率时含水率对冻结温度的影响占主导作用,超过时含盐量成为主要影响因素,且随着含水率增加两种含盐土导热系数增加速率均变缓。同时给出了不同条件下冻结温度和导热系数的经验公式,将水-盐-温度变量与冻结温度和导热系数建立起联系,为含盐土壤分布地区工程建设提供参考。     

瞬态法测量木材热物性的理论与实验研究

为了有效测量不同含水率木材的热物性，提出了一种新的瞬态平面热源测量法。在一定的简化条件下求解一维有限厚度平板的非稳态导热微分方程，得到了平板木材试样的温度随时间和平板厚度变化的短时间公式，并由此建立了在恒定热流加热条件下木材热物性的瞬态测量实验台。利用此实验台测量了不同含水率的落叶松和红松试样的径向导热系数、热扩散系数和比定压热容等热物性参数并与文献数据进行了比较。结果表明，该瞬态测量方法具有较高的精度，比准稳态法更好地满足了一维导热条件，利用此方法能够有效而快速地对不同含水率的木材进行热物性测量。     

粉煤灰陶粒轻骨料混凝土导热系数的研究

研究了不同导热系数测定方法、干湿状态、水灰比对粉煤灰陶粒轻骨料混凝土导热系数的影响。结果表明:采用防护热板法和脉冲法测量出的导热系数值相差不大;饱和状态下粉煤灰陶粒轻骨料混凝土的导热系数大于干燥状态下的导热系数;粉煤灰陶粒轻骨料混凝土的导热系数随水灰比的增大而减小。     

三维五向石英/环氧复合材料的热传导性

为了给三维编织复合材料在热传导方面的设计应用提供必要的依据,以石英纤维和环氧树脂为原料,制备三维五向石英/环氧复合材料,通过瞬变平面热源法测量复合材料的导热系数,分析纤维体积分数、编织角和不同减纱方法对复合材料轴向及径向热传导性能的影响.结果表明:三维五向编织复合材料的热传导性能沿着轴向和径向呈现出各向异性;其轴向导热系数随着纤维体积分数增大而增大,随着编织角增大而减小;其径向导热系数随着纤维体积分数和编织角的增大而增大;减纱会降低三维复合材料的热传导性能,与减纱线细度、分散减列相比,集中减列的影响最明显,轴向和径向导热系数分别降低了3.2%和3.0%.     

孔隙比与饱和度对粉质黏土导热系数影响的试验研究

以长春市城市快速轨道交通3号线东延线的粉质黏土为研究对象,制备不同条件下的重塑样.通过室内试验,利用DRPL-I型导热系数测试仪,采用稳态法测定不同条件下粉质黏土的导热系数,研究孔隙比与饱和度对粉质黏土的导热系数的影响.结果表明:粉质黏土的导热系数受其孔隙比与饱和度的影响;在一定条件下,当饱和度一定、孔隙比增大时,粉质黏土的导热性能减弱,导热系数随着孔隙比的增大而减小且呈近似线性减小;在孔隙比一定、饱和度增大的条件下,随着液相体积的增大,饱和度对粉质黏土的导热性能的影响有所提高,表现为导热系数随着饱和度的增大而线性增大.     

酸性磷铵料浆物性研究

分别用湿法工业磷酸（19．41％P2O5）和纯稀磷酸（23．68％P2O5）与气氨中和并行进行浓缩得到一系列不同中和度，不同含水率的酸性磷铵料浆。测这料浆的密度，沸点，导热系数，氟逸出率。结果表明，随料浆含水率和中和度的减小而增大，可通过ρ=k(ρax ρL(1-Xv)）进行预测。沸点在含水率低于40％区域变化较快，总的趋势随含水率和中和度的减小而升高。氟逸出率与含水率和中和度呈负相关，低中和度区氟逸出率较大且受中和度的影响非常显著，而在高中和度区，氟逸出率较低，较浆导热系数的范围为0．471－0.618W/(m.℃）。无固体颗粒析出时，料浆导热系数随含水率或中和度的减小而减小，当有固体颗粒析出时，料浆导热系数随含水率减小而增大。     

用瞬态平面热源法测定花生油的导热系数

利用瞬态平面热源法测量花生油在30²40℃下的导热系数,主要探讨了温度、测试时间、加热功率等参数对花生油导热系数的影响.结果表明:在低温和高温段,其导热系数随着温度升高而非线性增大;为使测量结果可靠,需设置合适的试验参数,其导热系数随测试时间和加热功率增加而稍微增大;但是在高温下,如果测试时间和加热功率设置偏大,会导致花生油发生对流传热,使试验结果误差很大.     

基于比等效热阻法的片状填料填充聚合物复合材料的导热性的预测

基于比等效热阻法建立了简化了的片状填料填充聚合物基复合材料的导热模型并推导出了相应的等效导热系数公式。以云母片填充聚乳酸为例,应用有限元软件ANSYS建立了云母体积分数在11％下的聚乳酸/云母复合材料的三维稳态热传导单元模型,并模拟了热流沿云母片厚度方向和径向传递的过程。结果表明,当热流沿云母片轴向方向上流动时,经ANSYS模拟求得的复合材料的等效导热系数和文中推导的公式的所给出的预测值更为接近;当热流沿云母片的径向流动时,随着云母体积分数的增加,复合材料的等效导热系数的预测值呈指数性增长,并且高于ANSYS的计算结果。有限元结果和本文的公式均表明,片状填料填充聚合物复合材料的等效导热系数可分解为是沿热流不同正方向上的贡献,更长的等效导热路径使片状颗粒在填充聚合物后能提供更为出色的导热性能。     

Analysis and calculation of thermal conductivity of rock in deep strata

The thermal conductivity of rock is an important parameter for the deep mine and the geothermal development. It is often not possible to measure the thermal conductivity of the rocks present in the deep strata, and the usual approach is to calculate thermal conductivity including mineralogy and porosity. The compositions of core samples from the MID01 borehole in the Bjorko area were determined, and the mineral composition was classified. The calculation of the thermal conductivity of rock in the borehole was carried out, and the main factors for the thermal conductivity of rock were analyzed. The results show that the calculated thermal conductivity of rock is reliable and useful for the design and calculation of geothermal development in the Bjorko area.     

Experimental study on thermophysical properties of C/C composites at high temperature

Ablationthermalprotectivecompositesarethekeystructureofspacevehiclesprotectingthemfromaerody namicheatingduringtheirreentryintotheaerosphere.Thecarbonmatrixcompositesarethemostpromisingablationmaterialsusedinthisenvironmentduetotheirpotentiallyfavorablepr…     

Analysis and calculation of thermal conductivity of rock in deep strata

The thermal conductivity of rock is an important parameter for the deep mine and the geothermal development. It is often not possible to measure the thermal conductivity of the rocks present in the deep strata, and the usual approach is to calculate thermal conductivity including mineralogy and porosity. The compositions of core samples from the MID01 borehole in the Bj?rk? area were determined, and the minera composition was classified. The calculation of the thermal conductivity of rock in the borehole was carried out, and the main factors for the thermal conductivity of rock were analyzed. The results show that the calculated thermal conductivity of rock is reliable and useful for the design and calculation of geothermal development in the Bj?rk? area. Foundation item: Project(50490274) supported by the National Natural Science Foundation of China; project supported by the Postdoctoral Science Foundation of China and Bj?rk? project supported by the Energy Agency of Sweden     

Seepage Anisotropy of Heterogeneous Body

Ore dumps are heterogeneous bodies with anisotropic seepage characteristics because of the ore segregation.In an indoor experiment, a dump was constructed with three strata, where the horizontal and vertical seepage experiments were carried out.Horizontals flow are regarded as phreatic plan flows without penetration.Its seepage law satifies the Dupuit equation.With parallel lay seepage model, the equivalent seepage coefficient in the horizontal flow was obtained and was equivalent to the weighted mean of the seepage coefficient of each stratum.An unsaturated flow appeared in the vertical experiment, with a hydraulic gradient of 1.The vertical flow was equivalent to the seepage model that moved in vertical bedding; its equivalent seepage coefficient depended on the stratum with the minimum seepage coefficient.That the experiment showed clear anisotropy in a heterogeneous body was obvious with an anisotropic coefficient between 63 and 155, which is 25 to 100 times larger than that of a homogeneous body.     

Changes in the thermodynamic properties of alkaline granite after cyclic quenching following high temperature action

During the development of hot dry rock, the research on thermal fatigue damage caused by thermal shock of cold and heat cycles is the basis that ensures the long-term utilization of geothermal resources,but there are not enough relevant studies at present. Based on this, the thermal damage tests of granite at different temperatures(250, 350, 450 °C) and quenching cycles(1, 5, 10, 15 cycles) were carried out.Preliminary reveals the damage mechanism and heat transfer law of the quenching cycle effect on hot dry rock. The results show that with the increase of temperature and cycles, the uneven thermal expansion of minerals and the thermal shock caused by quenching promote the crack development of granite,resulting in the decrease of P-wave velocity, thermal conductivity and uniaxial compressive strength of granite. Meanwhile, the COMSOL was used to simulate the heat transfer of hot dry rock under different heat treatment conditions. It concluded that the increase in the number of quenching cycles reduced the heat transfer capacity of the granite, especially more than 10 quenching cycles, which also reflects that the thermal fatigue damage leads to a longer time for the temperature recovery of the hot dry rock mass.In addition, the three-dimensional nonlinear fitting relationship among thermal conductivity, temperature and cycle number was established for the first time, which can better reveal the change rule of thermal conductivity after quenching thermal fatigue effect of hot dry rock. The research results provide theoretical support for hot dry rock reservoir reconstruction and production efficiency evaluation.     

基于细菌觅食算法的砂砾岩岩性识别方法

砂砾岩储层岩性复杂多变,母岩成分变化大,孔隙结构复杂,难以精确划分岩性并建立准确的解释模型,导致储层参数计算精度不高。针对松辽盆地梨树断陷砂砾岩储层特点,选择多组分体积模型作为该地区的测井解释模型,将该地层看成由局部均匀的孔隙、泥质、石英、长石、岩屑等5部分组成?根据多组分体积模型建立相应的测井响应方程,引入细菌觅食算法作多组分矿物模型的优化算法,将优化结果与岩芯分析孔隙度及全岩矿物分析的体积分数进行对比,结果验证了细菌觅食算法反演砂砾岩储层多组分矿物模型的可靠性。采用该方法对松辽盆地砂砾岩储层测井资料进行处理,取得了较好的结果。     

岩石的热导率对岩石热变质的影响

围岩的热导率是影响岩石热接触变质的主要因素之一。热导率较大的围岩,其热接触变质带较宽厚,变质程度较低;热导率较小的围岩,其热接触变质带较窄簿,变质程度较高。当热接触变质带发育完整,变质带较厚,变质程度较高时,蚀变岩、热液脉体和矽卡岩就不太发育。     

多孔介质有效导热系数的实验与模拟

应用实验与数值模拟相结合的方法研究了多孔介质的有效导热系数.将分形理论与孔道网络模型相结合的分形孔道网络模型用于研究多孔介质的有效导热系数,为太阳池储热、地源热泵传热、食品干燥等方面打下了基础.模拟计算结果与实验结果吻合较好,证明了分形孔道网络模型适用于计算多孔介质的有效导热系数.研究了孔喉比、配位数、垂直热流方向喉道比例、喉道长度、孔隙率、固体骨架导热系数(K.)及流体导热系数(Kf)等多方面对多孔介质有效导热系数的影响.结果表明,垂直热流方向喉道会增大多孔介质的热阻,降低多孔介质的有效导热系数.当K8大于Kf时,随着孔喉比的增大以及喉道长度的减小,多孔介质的有效导热系数越大.当平行热流方向喉道数目相等时,多孔介质的有效导热系数随着配位数的减小而增大;当垂直热流方向喉道数目相等时,多孔介质的有效导热系数随着配位数的增大而增大.