| 释义 |
permeameter|pɜːmiːˈæmɪtə(r)|
[f. permeability + -meter.]
1. An instrument for measuring the magnetic permeability of a substance or object.
1890S. P. Thompson in Jrnl. Soc. Arts 12 Sept. 885/2 Permeameter Method, this is a method which I have myself devised for the purpose of testing specimens of iron... For carrying it out a simple instrument is needed, which I venture to denominate as a permeameter. 1931Bureau of Standards Jrnl. Res. (U.S.) VI. 355 The permeameters in general use for commercial magnetic testing have an upper limit of about 300 gilberts per centimeter. 1936C. E. Webb in Vigoureux & Webb Princ. Electr. & Magn. Measurements ii. xii. 309 The average magnetic properties of a non-uniform specimen may often be found more accurately in the Fahy permeameter than in permeameters dependent on the production of equality of flux or of magnetic potential at a limited number of points in the magnetic circuit. 1969IEEE Trans. Magnetics V. 662/1 Straight magnetic samples are usually tested on hand compensated permeameters.
2. An instrument for measuring the permeability of a substance, esp. soil, to fluids.
1917G. A. Shakespear in Rep. & Mem. Advisory Comm. Aeronaut. No. 317. 3 The following is a brief account of a permeability tester which was designed for the rapid testing of balloon and airship fabrics... The apparatus (called a ‘permeameter’ for short) consists of a shallow cylindrical vessel of cast iron, about 13 cm. in diameter [etc.]. 1941D. P. Krynine Soil Mech. iii. 54 The general idea of permeameters or apparatus to determine the coefficient of permeability k in the laboratory is (a) to create a flow of water through a sample of a thickness L and having a definite cross section A [etc.]. 1971B. F. Curtis in R. E. Carver Procedures Sedimentary Petrol. xiv. 353 Although liquid permeameters are used when thought necessary, it is far more common to measure permeabilities using gas as the moving fluid. 1974A. Kézdi Handbk. Soil Mech. I. vi. 129/1 Constant head permeameters are particularly suited to the testing of highly pervious coarse grained soils. For soils with medium to low permeability, the falling head permeameters are used. |