Flowing wet vapor humidity measurement probe based on microwave heating and measurement method thereof

Abstract

The invention discloses a flowing wet vapor humidity measurement probe based on microwave heating and a measurement method of the probe. The probe is characterized in that flowing wet vapor is heated to form superheated vapor through microwaves, and then measurement on the wet vapor humidity is achieved. The wet vapor probe mainly comprises a sampling probe, a microwave heating section, a microwave source, a control circuit, temperature and pressure sensors and a data acquisition system, wherein the sampling probe is aligned to the flowing direction of wet vapor so as to achieve isokinetic sampling; microwaves generated from the microwave source are transmitted into a microwave resonance cavity through a coaxial line; moisture and vapor in flowing wet vapor inside the resonance cavity can simultaneously absorb microwave energy so as to be rapidly heated to form superheated vapor; data measured by the temperature and pressure sensors are displayed, processed and output through the data acquisition system, and then measurement on the humidity of flowing wet vapor is achieved. The probe is applicable to measurement on the humidity of flowing wet vapor at various flowing speeds, and in particular to measurement on the humidity of wet vapor inside a turbine.

Description

technical field [0001] The invention relates to a flow wet steam humidity measurement probe and a measurement method thereof, in particular to a flow wet steam humidity measurement probe based on microwave heating and a measurement method thereof. Background technique [0002] As a working medium, wet steam is widely used in various engineering practices, especially in the field of power engineering. For example, in a steam turbine, flowing wet steam not only causes the efficiency of the unit to decrease, but also causes water erosion to the cylinder and blades. Measuring the humidity of the flowing wet steam in the steam turbine (especially the humidity of the exhaust steam) is an important content of the thermal test of the steam turbine, and it is also an important basis for evaluating the performance of the unit and improving the design of the unit. [0003] Among the measurement methods of flowing wet steam in steam turbines, thermal and optical methods are relatively ...

AI Technical Summary

Problems solved by technology

The use of electric heating has disadvantages such as low heat transfer efficiency, long heating section, many links for heat dissipation and thermal inertia, difficulty in accurate measurement of heating capacity, and easy damage to heating elements, so that the humidity of wet steam cannot be accurately measured.

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