. The Bell System technical journal . (tangential-7^,) andthe angle (a) of wind direction from normal— diameter wire. of the wire. In the case of wire it increases from zero until theangle a (between the wind and the normal to the wire) is about 50° andthen decreases as this angle increases. The action is similar in the caseof wire except the maximum is reached when a is about 60°.Whether this shift in the maximum with the wire diameter is real, andhow far it would continue, is not clear since only two diameters ofwire were tested. For wire the variat
. The Bell System technical journal . (tangential-7^,) andthe angle (a) of wind direction from normal— diameter wire. of the wire. In the case of wire it increases from zero until theangle a (between the wind and the normal to the wire) is about 50° andthen decreases as this angle increases. The action is similar in the caseof wire except the maximum is reached when a is about 60°.Whether this shift in the maximum with the wire diameter is real, andhow far it would continue, is not clear since only two diameters ofwire were tested. For wire the variation in the force with FORCES OF OBLIQUE WINDS ON TELEPHONE WIRES 599 wind velocity when a equals 50° ranges from to poundper foot of wire for a range of velocities from 30 to 90 In thecase of wire and an angle {a) of 60° the variation rangesfrom to pound per foot of wire for the same range ofvelocities. As mentioned above the frame in which the wires were O K O 30 40 50 60 ANGLE a IN DEGREES Fig. 8—Graphic relation between the wind force along the wire (tangential-7^() andthe angle (a) of wind direction from normal— diameter wire. tested comprised such a major portion of the total resistance when theangle a approached 90° or the wind and wires were about parallelthat the data for these cases were not considered reliable. In plottingthe curves in Figs. 7 ( wire) and 8 ( wire) thetangential force for 90° was estimated and to indicate this the curvesare dotted between the angles a. of 80° and 90°. 600 BELL SYSTEM TECHNICAL JOURNAL 90 1 1 1 65 60 55 en UJ ^ 50O LUQ Z 45 U3 UJ -J 40uz< 35 I /I /l /I / f // 1 , /// 1 j / / 3025 II1 a/ /// //i } / / III] 7 / / 1 j II / 20 15 /, / o// y nil / / /^ // / y ^ / (^/^ / 105 / ^<:^ ^^o F^ ^ 0 ^ ^ 0 ^ ^^ ^ 30 40 50 60ANGLE OC IN DEGREES Fig. 9—Graphic relation between the angle (5) of direction of resultant force fromnormal
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
