New well-head device for shock-wave treatment of bottomhole zone

For the implementation of shock-wave treatment on bottomhole zone of formation, there are various devices not providing efficient resonant shakedown of borehole fluid column creating shock waves of pressure and vacuum, which is not efficiently productive and reliable as well. To reduce filtration resistances and reset hydrodynamic relation of the reservoir and well, a new construction of wellhead device for shock-wave treatment on bottomhole zone, which may be used for increasing oil recovery rate via the effect through the well on Productive Series during completion and repair of producing well, has been developed. By developing a reliable and constant pressed airflow with low pressure, the paper solves the task of increasing the frequency of closing and opening of wellhead device, enabling to use it for creating shocking waves of pressure and vacuum in the well. The implementation of developed device improving hydrodynamic relations and hereby, simplifying filtration in the “reservoir-well” system, puts in production low permeable and isolated zones of Productive Series, which promotes the oil recovery rate increase and reduce oil prime cost as well.

Contribution to the marine propeller hydrodynamic design for small boats in the Amazon region

ABSTRACTIn the Amazon, river navigation is very important due to the length of navigable rivers and the lack of alternative road networks. Boats usually operate in unfavorable conditions, since there is no hydrodynamic relation among propellers, geometry, and the dimensions of the boat hull. Currently, there is no methodology for propeller hydrodynamic optimization with low computational cost and easy implementation in the region. The aim of this work was to develop a mathematical approach for marine propeller design applied to boats typically found on Amazon rivers. We developed an optimized formulation for the chord and pitch angle distributions, taking into account the classical model of Glauert. A theoretical analysis for the thrust and torque relationships on an annular control volume was performed. The mathematical model used was based on the Blade Element Momentum Theory (BEMT). We concluded that the new methodology proposed in this work demonstrates a good physical behavior when compared with the theory of Glauert and the experimental data of the Wageningen B3-50 propeller.