Browsing by Author "Meyer, Neil"

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    Discharge measurement in terms of pressure differences at bridge piers
    (Stellenbosch : Stellenbosch University, 2000-12) Meyer, Neil; Rooseboom, A.; Stellenbosch University. Faculty of Engineering. Dept. of Civil Engineering.
    ENGLISH ABSTRACT: This study entailed the investigation and evaluation of a new methodology for measuring high discharges passing through bridges. Pressure differences generated around bridge piers have been measured and related to the discharges. These pressure differences are mainly functions of downstream flow conditions. The pressure differences have been converted into velocities by applying Newton's second law expressed in terms of the laws of conservation of energy; momentum; and of power. The energy principle was re-evaluated following a preVIOUSstudy (Retief, 1999) on a limited number of model pier combinations and flow conditions. Comparison of the energy approach with newly developed theories in terms of the momentum and power laws respectively led to the conclusion that the energy principle gave the best results. The question of applicability of the theory to practical pier/stream width and length ratios as well as its validity under flow conditions commonly found under flood conditions required that additional laboratory tests be done. The energy-based discharge equation was calibrated in terms of newly selected measuring points, different pier width and length ratios, as well as pier rotations for both super and sub-critical downstream conditions. According to the new tests performed at the Hydraulics Laboratory of the University of Stellenbosch on model piers, clear relationships were found between discharges and pressure differences measured against the pier. Calibration curves for practical flow measurement application were derived in terms of principle dimensionless parameters. Application of the energy approach at the prototype level needs further investigation.
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    Invited by God onto the worship stage : developing missional communities through participation in Theo-drama
    (AOSIS OpenJournals, 2013-09) Nell, Ian; Meyer, Neil
    When the front of the church begins to resemble a stage and the preacher, musicians and other leaders act like performers whilst the congregation takes on the role of an audience, then something is wrong with worship. But not only with worship: something is wrong with the church. A church longing to be missional – that is, a church in which all Christians are participants in the mission of God – needs to express that participation in its worship. Theological dramatic theory shows us how the Trinity acts out a grand narrative in creation, redemption and glorification, and invites us to participate in the Story being performed. This same narrative can be present in worship and can invite our immediate participation. But this cannot happen if either God or the congregation is relegated to the role of mere audience. However, when the Story is told and performed in worship and when the worshipping community is able to participate alongside the Trinity in the Theo-drama of worship, then worship takes on the ability to form that community missionally. Worship is a habit repeated week after week; therefore, its power to transform a community into a missonal congregation is immense.