声波测井相控线阵辐射器幅度加权的优化设计

对声波测井相控线阵声波辐射器进行了幅度加权的优化设计。分别针对辐射声束主瓣和旁瓣的最小化条件建立了相控线阵幅度加权的优化目标函数,采用拉格朗日乘子算法对目标函数进行非线性规划,并确定了最优幅度加权因子。通过数值计算对比分析了均匀幅度加权和不同幅加权条件下相控线阵声波辐射器的指向性以及辐射声束角宽的差异。结果表明,优化设计可以很好地实现相控线阵辐射旁瓣的最小化和给定旁瓣级条件下声束主瓣角宽的最窄控制,并且可以根据声波测井的不同要求提供相控线阵辐射器幅度加权的优化参数。

Optimization design of amplitude weighting for linear phased array transmitters in acoustic well logging

Optimization design of amplitude weighting for linear phased array acoustic transmitters in acoustic well logging was studied.Optimum weighting factors were determined by the method of augmented Lagrange algorithms.The optimum parameters in objective functions were searched for the case of minimization of main lobe width and side lobes respectively.Directivity and main lobe width were compared for the linear phased array acoustic transmitters with amplitude weighting and non-amplitude weighting using numerical examples.It is shown that the optimization design can make the side lobes minimize and the main lobe width narrow under a certain sound level of side lobes.The optimum method of amplitude weighting can be applied in acoustic well logging to provide appropriate parameters for the linear phased array acoustic transmitters in different cases.