解除方程组中n_0个变量为一组线性约束条件的数学处理方法

应用有限元方法数值求解流体力学或其他工程技术问题,通常所得n阶代数方程组具有线性和对称的性质.当方程组中有任意n_0(2≤n_0≤n)个待定变量为一组线性约束时,为解除这一约束,则可使用本文提供的数学处理方法,使原先n阶线性、对称的方程组在解除上述线性约束条件后,方程组的阶次不变,而且仍具有线性、对称的性质.     

泥浆滤液侵入对油藏岩石中油和水相对渗透率的影响

用模拟油藏注水驱油的不稳定状态法测定了油藏砂岩岩样的润湿性对油、水相对渗透率以及驱油效率的影响.测定结果表明,试验所用的油基和水基泥浆滤液的侵入均对油相渗透率造成相当严重的损害.油基泥浆滤液比水基泥浆滤液更容易使亲水砂岩转变为亲油砂岩.润湿性改变使油、水相对渗透率关系曲线发生明显变化.与亲水岩石相比.亲油岩石的驱油效率也明显下降.     

深源CO2及其对金的富集成矿作用

目的深源CO2与金成矿作用关系的研究是当前地学界倍受关注的前沿课题,介绍了深源CO2的特点。方法以国内外一些典型金矿研究资料为基础,结合我们近年从事矿床地球化学研究的成果,为深源CO2与金矿化间的联系提供了直接的地质证据。结果地球深部CO2储量巨大,且处于超临界状态,对金矿化有重要作用。结论深源CO2对金矿化的作用主要表现为运输成矿物质和提供巨大的能量两个方面。     

Helium and argon isotope trace in ore-forming fluid of Sawuer gold belt in Xinjiang,China

The helium and argon isotope compositions of fluid inclusions hosted in pyrite have been measured from Kuoerzhenkuola and Buerkesidai gold deposits in Sawuer gold belt, northern Xinjiang. The results show that fluidinclusion ^3He/^4He ratios are 0.64 Ra-4.25 Ra and 1.16 Ra-9.48 Ra, ^40Ar/^36Ar ratios are 282-359 and 312-525 for Kuoerzhenkuola and Buerkesidai gold deposits respectively.The ore-forming fluids of two deposits possessed the same source and derived mainly from mantle beneath the island arc (including oceanic crust and oceanic sediments by subduction of oceanic plate). They were diluted by incorporating meteoric water to form a mixture of mantle- and partial meteoric water-derived fluid. The ore-forming fluids of twodeposits are of the same evolutionary histories. From the early to the late mineralization stages, the ratios of meteoric water/mantle- derived fluid in ore-forming fluid increasedgrad ually. Based on these results and detailed geological and geochemical studies on the two deposits, it is proposed that the geneses of the two gold deposits are the same, being volcanogenic late-stage hydrothermal gold deposits occurring in the same volcanic apparatus.     

An investigation of water-gas interface migration of the upper Paleozoic gas pool of the Ordos Basin using reservoir fluid inclusion information

There is a particular characteristic in the formation of the Upper Paleozoic gas pool in the Ordos Basin that is its water-gas interface migrated regional during geological history. However, there has been lack of detailed research on this problem and also no similar report on other basins. In this paper, the formation time of the fluid inclusions formed in the water-gas transition zone of the gas pool was deduced using their trapping temperatures and combining of the burial with geothermal history of the basin. On the basis of this, the isochrone of water-gas interface migration for the gas pool was mapped. The result shows that the gas pool began to form around the Yanan Area at about I65Ma, and then developed and enlarged toward the north direction. The gas pool finally formed at about 129 Ma. Since the basin uplifted from the late Cretaceous and gas supply decreased, the water-gas interface of the gas pool migrated back to the present position.     

催化裂化装置的用能分析与改进

基于流化催化裂化过程的特点及过程系统三环节能量结构模型,对国内某炼油厂催化裂化装置进行了能量和火用分析,提出了相应的用能优化改进措施。通过采取优化分馏塔回流取热、增加高温位中段及油浆等循环取热、增设烟机回收装置烟气压力能、优化换热网络和利用装置低温热等措施,可使装置能耗大幅度降低,节能效果显著。     

一种用于污垢监测的温差热阻新方法

在恒壁温条件下,在结垢过程中,管内流体温度和垢层内壁面温度逐渐降低,会引起流体与内壁面间对流传热热阻增加,因而必须对现有的计算污垢热阻的公式进行修正。综合考虑各种因素,建立了恒壁温条件下计算污垢热阻的改进模型。计算实例表明,其他条件一定时,流体进口温度越低,流量越小,则修正值和修正系数越大。随着结垢过程的进行,修正值增大,修正系数减小。在结垢的初始阶段,修正系数最大,说明应用改进公式计算的结垢诱导期较长,更接近于实际情况。     

一体化电机系统中传导干扰抑制方法的研究

为了抑制一体化电机系统中的传导干扰，分析了一体化电机系统传导干扰的产生机理及其耦合途径．根据干扰机理、耦合途径及干扰源的分布，分别采取相应的抑制措施．功率器件的电压过冲和电压变化率可以通过缓冲电路来进行抑制．基于传导干扰的耦合途径不同，以变流器为界，前后分别从漏电流和共模电压的角度进行抑制，采用有源滤波来补偿漏电流和消除共模电压．在理论分析的基础上，设计了用于抑制传导干扰的新型滤波器．实验结果证明，增加缓冲电路和滤波器后，一体化电机系统的传导干扰强度明显减弱．     

蓄热室三维非定常流动与传热数值研究

蓄热室是蓄热式高温空气燃烧系统实现余热回收和获得高温空气的关键部件。应用多孔介质模型模拟蓄热体，采用当量连续法建立蓄热室非定常流动和传热的三维模型，对采用蜂窝陶瓷蓄热体的蓄热室在蓄热过程和放热过程中流速和温度的动态分布情况进行研究。     

塔里木盆地火成岩对碳酸盐岩储层的改造作用

塔里木盆地形成与演化过程中出现过多期的岩浆侵入与喷发活动,形成了多种类型的火成岩体.岩浆活动形成的火成岩带来了地壳深部的热液流体,其中富含二氧化碳、硫化氢、硫、及少量一氧化碳、氢、HCl、NH3、NH4Cl、HF等的酸性流体对上部碳酸盐岩储层产生了多种多样的改造作用,包括大理岩化作用、萤石化作用、热液白云岩化作用、热液溶蚀作用等.多种改造作用的结果,使得原本致密的碳酸盐岩储层,形成了大量各种类型的孔洞,孔隙度大大增加,储集性能得到改善.勘探过程中,火成岩的出现可以预示附近地区良好储层的发育,为勘探油气起到了示踪作用.