During steam wetness measurement by microwave resonator

water film and salt will deposit on the resonant cavity's inner surface.The effect of the deposited dielectric on the resonant frequency was analyzed

and its influence on the steam wetness measurement was also investigated.The results show that:thinner film had less effect on the steam wetness measurement

but this effect aggravated with the film thickness;with the same water film thickness

the wet steam pressure(temperature)had little effects on resonant frequency

and the effect of water film on steam wetness measurement decreased slightly with an increase in wet steam pressure(temperature);the effect of deposited water film on measurement was greater than the deposited salt;however

when this method was applied in the turbine's exhaust wetness measurement

the thickness of water film deposited on the resonator's inner surface was less than 35μm

and the deviation of wetness measurement was no more than 1.262%.