Bulletin . ibrium of From the three figures it is found that theaverage temperature indicated by the three thermocouples embeddednear the hotter surface of the air space is 514° C, ordinary scale, or1,418° on the absolute scale, and the average of the indicationsof the three couples embedded near the colder surface is about 408° C,ordinary scale, or 1,227° F., absolute scale. We have then: Tj-1,418° F. and T2=1,227°F. a It should be remembered, however, that in the experiments discussed the junctions of the thermo-couples were embedded In the brick about 1 incli from the surf
Bulletin . ibrium of From the three figures it is found that theaverage temperature indicated by the three thermocouples embeddednear the hotter surface of the air space is 514° C, ordinary scale, or1,418° on the absolute scale, and the average of the indicationsof the three couples embedded near the colder surface is about 408° C,ordinary scale, or 1,227° F., absolute scale. We have then: Tj-1,418° F. and T2=1,227°F. a It should be remembered, however, that in the experiments discussed the junctions of the thermo-couples were embedded In the brick about 1 incli from the surface, and therefore the assumed tempera-tures are farther apart than the actual temperatures were. Necessarily, higher values of the net heat exchanged or radiated will result when these assumed tem-peratures are used in computation. The exact location of the Junctions of (lie thermocouples could not bedetermined, and therefore no accurate and reliable correction of the surface temperatures can be made. 24 FLOW OF HEAT THEOUGH FURNACE WALLS. 60 The net radiation corresponding to these temperatures can be foundapproximately from figure 17 in the following manner: On the scale at the foot of the chart locate the temperature of1,227° F., absolute, the temperature of the colder surface. Thistemperature will be found between the points of 1,200° and 1,300°F. After locating this point, follow an imaginary vertical line risingfrom it and cutting the curve of 1,418° F. This curve, though not on the chart, can be imag-ined in its proper placebetween the curves of1,400° and 1,500° the intersection ofthe two imagined lines,draw a horizontal line tothe scale on the left,which gives the heat inBritish thermal unitsradiated per minute persquare foot of the hot-ter surface. In the caseunder consideration, theradiated heat is foundto be 44 B. t. u. forsooted surfaces. Theradiation for brick sur-faces is obtained b}T mul-tiplying 44 by the coef-ficient of heat exchangefor bric
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