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141.
The directional spreading of both the wavenumber and frequency spectra of finite-depth wind generated waves at the asymptotic depth limit are examined. The analysis uses the Wavelet Directional Method, removing the need to assume a form for the dispersion relationship. The paper shows that both the wavenumber and frequency forms are narrowest at the spectral peak and broaden at wavenumbers (frequencies) both above and below the peak. The directional spreading of the wavenumber spectrum is bi-modal above the spectral peak. In contrast, the frequency spectrum is uni-modal. This difference is shown to be the result of energy in the wind direction being displaced from the linear dispersion shell. A full parametric relationship for the directional spreading of the wavenumber spectrum is developed. The analysis clearly shows that typical dispersion relationships are questionable at high frequencies and that such effects can be significant. This result supports greater attention being focussed on the routine recording of wavenumber spectra, rather than frequency spectra. 相似文献
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A mathematical model is developed for predicting the temperature distribution in an aquifer thermal energy storage (ATES) system, which consists of a confined aquifer bounded from above and below by the rocks of different geological properties. The main transfer processes of heat include the conduction and advection in the aquifer and the conduction in the rocks. The semi‐analytical solution in dimensionless form for the model is developed by Laplace transforms and its corresponding time‐domain solution is evaluated by the modified Crump method. Field geothermal property data are used to simulate the temperature distribution in an ATES system. The results show that the heat transfer in the aquifer is fast and has a vast effect on the vicinity of the wellbore. However, the aquifer temperature decreases with increasing radial and vertical distances. The temperature in the aquifer may be overestimated when ignoring the effect of thermal conductivity. The temperature distribution in an ATES system depends on the vertical thermal conduction in the rocks and the horizontal advection and thermal conduction in the aquifer. The present solution is useful in designing and simulating the heat injection facility in the ATES systems. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
146.
This paper presents a finite‐element (FE) model for simulating injection well testing in unconsolidated oil sands reservoir. In injection well testing, the bottom‐hole pressure (BHP) is monitored during the injection and shut‐in period. The flow characteristics of a reservoir can be determined from transient BHP data using conventional reservoir or well‐testing analysis. However, conventional reservoir or well‐testing analysis does not consider geomechanics coupling effects. This simplified assumption has limitations when applied to unconsolidated (uncemented) oil sands reservoirs because oil sands deform and dilate subjected to pressure variation. In addition, hydraulic fracturing may occur in unconsolidated oil sands when high water injection rate is used. This research is motivated in numerical modeling of injection well testing in unconsolidated oil sands reservoir considering the geomechanics coupling effects including hydraulic fracturing. To simulate the strong anisotropy in mechanical and hydraulic behaviour of unconsolidated oil sands induced by fluid injection in injection well testing, a nonlinear stress‐dependent poro‐elasto‐plastic constitutive model together with a strain‐induced anisotropic permeability model are formulated and implemented into a 3D FE simulator. The 3D FE model is used to history match the BHP response measured from an injection well in an oil sands reservoir. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
147.
Statistical models are proposed for the distribution of directions in three dimensions that are thought to point toward a single source. These models are based on the Fisher distribution. The method of maximum likelihood is used to obtain an estimate of position of the source and to provide corre-sponding confidence regions. When applied to shatter cone data from the Slate Islands, northern Lake Superior, the method yields estimates comparable with those obtained by Stesky and Halls (1982), as well as statistically valid confidence regions. 相似文献
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应用三维地震资料设计水平井的轨迹,用人工合成记录标定层位和岩性并进行精细的构造解释和储层横向预测,对测区速度场进行研究,利用Geoquest 人机联作解释系统编绘层拉平图、转弯测线剖面图,不整合面构造图,各套油层顶面构造图,沿地层倾向设计水平井的轨迹.经两口井钻探,钻遇不整合面的误差0.19%—0.39%,一口井平均钻遇油层204m,相当9口直井的效益.用地震资料设计巷道水平井的关键是油层标定、深度标定和确定油层走向,用人机联作系统绘制水平切片图、反射波振幅图、油层顶构造图,设计了在油层内钻探的巷道井.经钻探,钻遇不整合面的误差0.07%,在真厚度8.23m 的油层内钻进563m. 相似文献
149.
本文提出了利用单孔进行弥散实验,确定地下水含水层弥散度的新方法,给出了数学模型、求解过程及方法。提出了用计算机自动处理求得最佳参数的直线回归法与非线性迭代法相结合的方法。不但进行了理论上的详细推导,而且通过实例进行了验证,结果很好。本文提出的方法原理通俗易懂,计算过程简单,易于实行,成本低,具有重要实际意义。 相似文献
150.
Yang Hui-nian 《地震地质》1991,13(4):312
Field investigation on hydrogeological environment around Changping well reveals that the anomalous uprise of 'water table begining from Oct. 1988 was mainly caused by the leakage of water from the channel leading to Shisanling Reservoir, but not the precursor of Datong-Yanggao earthquake in Shanxi Province in 1989 相似文献