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91.
克拉2气田储层岩石的应力敏感性及其对生产动态的影响 总被引:9,自引:2,他引:7
克拉2气田是一个异常高压气藏,压力系数在2.0以上。在衰竭式开采条件下,其地层压力降幅可为普通气藏地层压力降幅的3倍以上,因此研究储层岩石应力敏感性及其对生产动态的影响意义重大。研究得出,岩石的应力敏感性特征主要有:岩石物性对应力的敏感性总体上不大,其中以孔隙度最小,渗透率次之,压缩系数最大;岩石物性随地层压力的下降而下降;在同一地层压降下.岩石物性下降幅度不是渗透率的连续函数,而是与渗透率分布范围有关,高渗透率范围,岩石物性下降幅度小,低渗透率范围,岩石物性下降幅度大。研究得出,克拉2气田岩石的应力敏感性对其生产动态的影响较小。 相似文献
92.
葛翔 《石油化工安全环保技术》2006,22(4):37-38,43
阐述了现场总线技术的含义、主要特点和优点,对比了现场总线控制系统与DCS系统的区别,介绍了现场总线技术在洛阳石化分公司热电站的典型应用及其发展前景。 相似文献
93.
94.
工业现场的温度变化范围大而剧烈,工作在工业现场的传感器大多数都对温度有一定的敏感度,这样就会使传感器的零点发生漂移,导致测量出现附加误差,因此温度补偿问题一直是传感器技术中的关键环节。根据单总线数字式温度传感器DS18820的工作原理、结构,并以电阻应变式传感器为例,提出了具体的补偿方案。 相似文献
95.
A 1-D transient model (RESHEAT), developed by the writers, was used to study the thermal performance of a highly reflective paint applied sequentially to the outer walls and roof of a simulated residence in a hot and arid region of the southwestern United States. The model uses climatological inputs from a file that includes hourly data on ambient temperatures, insolation, cloud cover, and so on, at the particular location. The model focuses particularly on the potential cooling load reduction due to the reduced heat pickup from the inside attic surfaces to the outer surfaces of the supply duct. This simulation showed that a reduction of 33.6% (cooling load) on the average is achieved over the base case where no reflective paint is used when the outer surface of the roof and walls are painted. Alternatively, only a 11% reduction would be achieved if the reflective paint is applied only to the roof. Savings of $42 per month are conservatively estimated from calculations made when applying this technology to a typical residence (roof and walls) equipped with a 4 ton refrigeration unit in the Southwest. 相似文献
96.
Woo Yong Sung Seung Min Lee Wal Jun Kim Jong Girl Ok Ho Young Lee Yong Hyup Kim 《Diamond and Related Materials》2008,17(6):1003-1007
Complementary electroplating combined with electrophoresis enhanced the field emission characteristics of emitters by improving the adhesions between CNT emitters and substrate. The emitting current of the CNT emitters prepared by our combined method increased nine times higher than that of CNT emitters prepared by electrophoresis only, since electroplating improved the adhesion of CNT emitters. During the life-time measurement for 10 h, the emitting current of CNT emitters fabricated by electrophoresis only was drastically decreased to 13% of the initial current, while that prepared by the combination of electrophoresis and successive electroplating decreased to 64% of the initial current. We suggest that our method is a promising approach for the efficient fabrication of reliable CNT emitters. 相似文献
97.
The temperature programmed (palladium) hydride decomposition appeared very effective method for diagnosing the extent of alloying in Pd-Pt/SiO2 catalysts. Introduction of Pt to Pd catalysts moves the TPHD peak gradually towards lower temperatures and the shift in hydride decomposition peak is accompanied by a decrease in the amount of released hydrogen. The catalysts prepared the direct redox method showed much better alloy homogeneity than the samples prepared by coimpregnation. The results of probing with other techniques, i.e. catalytic probing with hydrodechlorination of CCl2F2 and XRD, were in line with TPHD data. The catalytic probing showed the presence of synergistic effect, a clear indication of Pd-Pt mixing. XRD data of post-reaction samples showed carbon incorporation into Pd-rich phase, whereas separate Pt-rich phase did not experience any bulk carbiding. 相似文献
98.
In order to enhance the performance of self-consolidating concrete, it is important to have a better understanding of the rheological behavior of the material. The initial rheological parameters and their variations with time are closely affected by material temperature, type and dosage of high range water-reducing admixture (HRWRA), and elapsed time. This paper presents the results of an investigation aimed at evaluating the coupled influence of time and temperature on the variations of yield value with time of mortars made with two types of HRWRA: polynaphtalene sulfonate and polycarboxylate polymer. Four mortars extracted from self-consolidating concrete mixtures proportioned with various binder types and with water-to-binder ratios of 0.42 and 0.53 were prepared at 10 to 30 °C.Test results show that the yield value varies linearly with the coupled effect of time and temperature during the dormant period for mixtures made with polynaphtalene sulfonate-based HRWRA. However, such changes are found to depend on the mixture temperature for mixtures made with polycarboxylate-based HRWRA, which can influence the dispersion efficiency of the polycarboxylate polymer. The threshold temperature of mixtures made with PCP-HRWRA is shown to vary with mixture composition. Below a given threshold temperature, the mortar exhibits a considerable degree of retention or even reduction in yield value over 30% of the dormant period. A sharp increase in yield value is observed beyond 30% of the dormant period. Above this threshold temperature, the yield value is shown to increase linearly with time. 相似文献
99.
Mapping surface temperature in large lakes with MODIS data 总被引:1,自引:0,他引:1
Satellite sensor MODIS on two platforms can produce Sea Surface Temperature over certain regions about three to four times per day. Our objective was to test if the MODIS SST product can be applied for lakes whose surface areas are large enough to be observed at the MODIS spatial resolution and to compare the satellite-derived lake surface temperatures with in situ measurements. Surface temperatures for Lakes Vänern and Vättern in Sweden, two of the largest European lakes, are extracted from the MODIS/Terra images for period 2001-2003. The results are analyzed on different quality levels, as all MODIS L2 products are equipped with an additional quality flag. We present temperature development over 2001-2003, and show the capability of the MODIS SST product to couple the known thermodynamical features in the lakes under study, where temperature varies greatly with space and time. These results can complement lake monitoring programs anywhere. 相似文献
100.
川东北飞仙关组高含硫气藏气井在完井测试过程中,压力测点位置与产层中部的距离较大,需将压力数据用气柱压力计算公式折算后再进行试井分析解释。文章以质量、动量和能量三大守恒方程和状态方程为基础,考虑了流动气柱的动能损失以及井筒和地层中复杂的传热机理,推导出计算单相气流在井筒不同部位压力和温度的方法。以坡2井为例,应用目前最新的模块化动态地层测试器MDT地层测试技术,对折算的压力进行了验证和对比分析。结果表明,应用文中的压力计算方法,完全可以满足解释的压力数据精度。另外,在没有进行完井测试前利用MDT测压资料确定地层压力等储层参数是较为直接和可靠的方法。同时此法对川东北飞仙关组高含硫气藏的开发动态监测以控制元素硫在井底和井筒的沉积具有十分重要的指导意义。 相似文献