MOISTURE DIFFUSION COEFFICIENT DETERMINING METHOD Russian patent published in 2014 - IPC G01N13/00 

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment and can be used at investigation of processes of mass transfer in capillary porous materials for determination of moisture diffusion coefficients of building materials and structures, as well as in food, chemical and other industries. A moisture diffusion coefficient determining method consists in creation in the investigated specimen of uniform initial moisture content, bringing of flat surface of the specimen in contact with the environment with moisture content different from that of the specimen. Besides, the method involves measurement of variation in time of a signal of a galvanic converter, determination of time of achievement of maximum in a curve of variation of EMF of the galvanic converter and a calculation of the diffusion coefficient. Pulse moistening of the flat surface of the investigated specimen is performed along the straight line; after that, the same surface is hydrolysed; electrodes of the galvanic converter are located at two points of the same flat surface in a line parallel to the line of application of pulse voltage and at the specified distance from it, and the required coefficient is calculated by the formula: $$D=r_0^2/(4{\tau }_{\max }),$$ where τ_max - time of achievement of maximum in the curve of variation of EMF of the galvanic converter, r₀ - distance between the pulse moistening line and the location line of electrodes of the galvanic converter.

EFFECT: increasing speed of an experiment and providing a possibility of non-destructive testing of a diffusion coefficient in massive items from capillary porous materials.

1 dwg, 1 tbl