Condenser transducer method

A review of the common methods of measuring acoustic absorption and dispersion is presented by Cottrell and McCoubrey [9], The ultrasonic interferometer, the absorption tube, the condenser transducer, and the reverberation chamber are the standard types of apparatus. 

The most straightforward method for vapor-pressure measurement is the static method, in which the pressure of the vapor above a pure liquid is measured directly with a manometer, pressure gauge, or pressure transducer. All parts of the apparatus must be maintained at a temperature at least as high as that of the sample in order to avoid condensation. Static techniques may be used at high temperatures and pressures with appropriate apparatus construction, but they become difficult at low vapor pressures due to the difficulty of pressure measurement and the effects of impurities. With good equipment and procedures, the accuracy of static vapor pressure measurements can be on the order of 0.1%. 

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