15 research outputs found

    Gas Storage Technology Consortium

    Full text link

    A Uniform Linear Multi-Coil Array-Based Borehole Transient Electromagnetic System for Non-Destructive Evaluations of Downhole Casings

    No full text
    Borehole transient electromagnetic (TEM) techniques have been proven to be efficient for nondestructive evaluations (NDEs) of metal casings using eddy-current properties. However, physical limitations and bad borehole conditions restrict the use of eddy-current sensors, which makes downhole casing inspections very different from those of conventional NDE systems. In this paper, we present a uniform linear multi-coil array-based borehole TEM system for NDEs of downhole casings. On the basis of the borehole TEM signal model, a numerical multi-coil array approach using the Gauss–Legendre quadrature is derived. The TEM response can be divided into two independent parts related to the transmitting-receiving distance (TRD) and the observation time and casing thickness. Using this property, the signal received by the multi-coil array is weighted to cancel the influence of the TRDs of the different array elements to obtain the optimal response according to the linearly constrained minimum variance criterion, which can be shown to be identical to that of achieving the maximum signal-to-noise ratio. The effectiveness of the proposed method was verified by applying the uniform linear multi-coil array to a borehole TEM system for NDEs of oil-well casings. Field experiments were conducted, and the results demonstrate the effectiveness of the proposed method

    Energy: A continuing bibliography with indexes

    Get PDF
    This bibliography lists 1428 reports, articles, and other documents introduced into the NASA scientific and technical information system from January 1, 1980 through March 31, 1980

    Energy: A continuing bibliography with indexes, issue 15

    Get PDF
    This bibliography lists 1112 reports, articles, and other documents introduced into the NASA scientific and technical information system from July 1, 1977 through September 30, 1977

    Multiphase Flow Simulations in Large Domains of Upper Maastrichtian Chalk

    Get PDF

    Specific Surface Area Determination on Chalk Drill Cuttings

    Get PDF
    corecore