|Theodoros Theodoulidis |
University of Western Macedonia, Greece, Joined Dec 1999, 5
Wood moisture measurement
I believe that the two main methods of wood moisture measurement are:
1) The drying oven method
2) The electric method
I want to ask if I can measure it by using UT, since I have seen that ultrasonic velocity is affected by moisture content.
Is there active research on the subject?
|Bernd Wolter, IZFP, Saarbruecken, Germany |
Re: Wood moisture measurement You also can measure moisture by a variety of other nondestructive methods. Some companies offer commercial hand-held sensors based on electrical resistivity measuring for wood moisture determination. Besides, dielectric methods (capacitice methods, microwaves, time-domain reflectometry), thermographic methods and x-ray methods are used for it.
A survey about wood moisture measurement is given by: Melhorn L., Plinke B.; "Zum Stand der Feuchtemessung an Massivholz", Holz-Zentralblatt 120, p. 1837, 1990 (in German). Ultrasound for wood moisture measurement is used e.g. by: Bernatowicz G., Matejak M.; "Application of Ultrasound Time Measurements for Moisture Content detection During Drying", Proc. 1st Europ. Symp. Nondestructive Evaluation of Wood, 21.-23. Sept. 94, Sopron, Paper 4, 1994.
At IZFP, we are using NMR (Nuclear Magnetic Resonance) in One-Sided Access for depth-profiling of the moisture content in wood. In contrast to other nondestructive methods, NMR does also allows to determine detph-profiles of wood density. Therefore it is possible to determine absolute moisture contents in mass-%.
|Wieslaw Bicz |
Re: Wood moisture measurement : I believe that the two main methods of wood moisture measurement are:
: 1) The drying oven method
: 2) The electric method
: I want to ask if I can measure it by using UT, since I have seen that ultrasonic velocity is affected by moisture content.
: Is there active research on the subject?
Such research can be relatively easy done. If you are interested, we can test it, using transmission of air ultrasound through the wood.
We have ready made devices, suitable for this purpose.
It seems for me, that it should work, but needs many tests to calibrate the measurement.
|Nikolay Kostadinov Ganchev |
Re: Wood moisture measurement Dear sir
Please,send my more information for wood moisture measurement and methods of wood moisture measuring.
|Joseph Pascente |
Lixi, Inc., USA, Joined Nov 1998, 39
Wood moisture measurement The Lixi Profiler will measure moisture amount in wood
whose thickness is the same.
|nazmi yetim |
Re: Wood moisture measurement : Dear sir
: Please,send my more information for wood moisture measurement and methods of wood moisture measuring.
|N.T. Azarov |
GosNIIGA, Russia, Joined Jan 2000, 12
Re: Wood moisture measurement : : Dear sir
: : Please,send my more information for wood moisture measurement and methods of wood moisture measuring.
We develop a meter of humidity of wood by a capacity method - "humidity meter VD-1". The instrument allows to measure of relative (%) humidity of wood on depth up to 30-40mm, while other similar instruments measure humidity only in surface layers. The instrument has the switch, depending on a type of a tree.
Nowadays instrument is used by us for definition of presence of a moisture in aircraft honeycomb constructions from composite materials.
The instrument is portable, mass 200g. The power supply is carried out from the accumulator.