Furthermore, effective heating test methods have not been developed for downhole transducers. The existing experimental research only considered the underwater acoustic characteristics of the transducer and did not pay attention to the temperature effects on the transducer. Experimental tests are an important method to study the performance of transducers. Simultaneously, the logging tool works in the downhole high-temperature environment, and the effect of different temperatures on the piezoelectric vibrator must also be considered. The measurement results will be wrong if the parameters of the piezoelectric vibrators are inconsistent. The energy, frequency response, and azimuthal resolution of piezoelectric vibrators have a considerable effect on the measurement results. The installation of multiple piezoelectric vibrators in the circumferential direction is necessary to realize the downhole azimuthal measurement. All these research results are references for improving the downhole measurement in future. Furthermore, data-driven approaches to solving complex downhole measurement problems were proposed. The methodology based on external and embedded sensors is effective in crack detection. theoretically analyzed the contributions of the poroelastic-wave potentials to seismoelectromagnetic wave fields and calculated the magnetic field using a curl-free electric field. developed a new LWD method with a seismoelectric effect and performed seismoelectric LWD measurements in a scaled sandstone borehole with multipole sources (monopole/dipole/quadrupole). Bennett developed 3D slowness time coherence (STC), and the slowness and propagation direction of a reflected wave field can be determined using a simple ray-tracing inversion and 3D STC. The acoustic LWD experimental measurements were conducted to analyze the excitation and propagation of monopole collar waves in the laboratory. The wave fields of a monopole sound source applicable to the logging while drilling (LWD) model were investigated, and the propagation mechanisms of collar waves in the LWD models were revealed. Hirabayashi developed high-resolution reflector imaging methods using a trial reflector and cross correlation. The research on new technologies and methods has promoted the development of acoustic logging and provided more solutions for solving complex downhole acoustic measurement problems. Hence, this experimental study can provide a foundation for the design and matching selection of azimuthal-transmitting piezoelectric vibrators. After cooling to room temperature, the parameters of the vibrator are consistent with those before heating. The resonant frequency first increases and then decreases slightly with an increase in temperature. The peak-to-peak amplitude radiated from the azimuthal vibrator and the static capacitance increase with an increase in temperature. The main lobe angle of the radiation beam, horizontal directivity, and radiation energy of the azimuthal vibrators and azimuthal subarray are measured. The transmitting piezoelectric vibrators showing a good consistency in the heating test were selected, and an underwater acoustic experiment was performed. This paper presents a heating test apparatus and studies the admittance and driving responses of the vibrator at different temperatures. Therefore, this paper proposes an experimental method to comprehensively evaluate downhole azimuthal transmitters furthermore, we analyze the azimuthal-transmitting piezoelectric vibrator parameters. However, effective heating test and matching methods are not yet developed for downhole multi-azimuth transmitting transducers. To realize downhole azimuthal detection, assembling multiple transmitting piezoelectric vibrators in the circumferential direction is necessary, and the performance of azimuthal-transmitting piezoelectric vibrators needs attention. Azimuthal acoustic logging can survey the downhole formation more accurately, and the acoustic source is the crucial component of the downhole acoustic logging tool with azimuthal resolution characteristics.
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