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The heating efficiency of sodium chloride solution would be increased with elliptically polarized microwave electric field for that a more frequent motion of water molecules and ions would be generated with multidirectional polarization electric field. [Display omitted] • The heating efficiency of sodium chloride solution with elliptically polarized and linearly polarized microwave electric field was compared. • Rotation autocorrelation function was used to study rotating motion of water molecules with different heating modes. • The hydrogen bonds between water molecules of sodium chloride solution were simulated. Our molecular dynamics simulation results show that the elliptically polarized microwave electric field would increase the heating efficiency of sodium chloride solution. The growth rate of the heating efficiency is positively correlated with the concentration of the sodium chloride solution and intensity of applied electric field. The rotation autocorrelation function results confirm that water molecules would do a more frequent rotational motion with the multidirectional polarization of elliptically polarized microwave electric field. The result of the more frequent rotational motion is consistent with that of the higher microwave energy absorption of energy analysis. The following analysis of hydrogen bond shows that the existence of ionic solutes would break the hydrogen bonds between water molecules and make it easier for water molecules to rotate with the applied electric field. These results indicate that elliptically polarized microwave electric field can indeed improve the heating efficiency of salt solution. [ABSTRACT FROM AUTHOR]

Microwave power combining based on dual 15-kW continuous-wave (CW) magnetrons in S-band is presented. The injection locking on 15-kW CW magnetrons has been successfully accomplished. The phase-locking bandwidth of each magnetron reaches 5 MHz with an improved dc power supply. Meanwhile, phase jitters are measured and analyzed briefly. The injection-locked 15-kW magnetrons have stable magnitude and tunable locked phase, which are suitable for coherent power combining. A dual-magnetron microwave power combining system has been designed and developed with an automatic phase controlling mechanism. The microwave power combining efficiency is higher than 95%. It is the first time to demonstrate a successful microwave power combining of dual 15-kW S-band CW magnetrons. The system will find industrial applications in producing diamond film from microwave plasma chemical vapor deposition. Large-power and high-efficiency microwave sources based on power combining from magnetrons are good candidates for industrial applications. [ABSTRACT FROM PUBLISHER]

Phase-control precision is important for applications of magnetrons in the microwave source array. Here, experimental results use a 20-kW $S$ -band continuous-wave magnetron to investigate the phase deviation of large-power phase-locked magnetrons. For the first time, the phase deviation of a 20-kW magnetron controlled through an externally injected signal was studied. The phase deviation of the injection-locked magnetron output worsened gradually, the greater the difference in frequency of the injected signal (with the same injection ratio) from the center of magnetron injection-locked bandwidth was. When the injected power was maintained at 150 W and the magnetron output was at 19 kW, the maximum phase deviation was varied from approximately 1° to 6° with frequency tuning. In addition, the phase deviation of the phase-locked magnetron decreased as the injected signal power increased at a given frequency. [ABSTRACT FROM AUTHOR]