. A new thermo-electric fluid-meter and hot-wire anemometer. £fGU/i£: -^O. 267 wire, the instrument is essentially operated on directcurrent. In one form of the Fluid-Meter, as indicatedin figure 39, the battery B acts as a source of currentfor the electrically heated wire or filament ab, made offine sized Wo, 36 B. & S. Gauge or smaller) advance. Thevalue of current through the heating filament may bevaried from zero to the maximum allowable heating-current by means of the adjustable regulating resistanceR. The milli-ammeter A indicates the value of this heat-ing-current which causes the rise
. A new thermo-electric fluid-meter and hot-wire anemometer. £fGU/i£: -^O. 267 wire, the instrument is essentially operated on directcurrent. In one form of the Fluid-Meter, as indicatedin figure 39, the battery B acts as a source of currentfor the electrically heated wire or filament ab, made offine sized Wo, 36 B. & S. Gauge or smaller) advance. Thevalue of current through the heating filament may bevaried from zero to the maximum allowable heating-current by means of the adjustable regulating resistanceR. The milli-ammeter A indicates the value of this heat-ing-current which causes the rise in temperature of thefine resistance wire ab, the rise in temperature beingdirectly proportional to the square of the current (i ),as the resistance r does not vary by an appreciable amount. At the central point of this heating filamentthere is welded or fused a fine wire of Therlo orManganin, the length of which is made small, about aneighth or a quarter of an inch, so that the coldjunction of the couple is subject to practically thesame temperature changes as the
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License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, bookidnewthermoele, bookyear1920
