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Full text of "The Flow Of Gases In Furnaces"

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These computations may be made in the English units, if desired.
Should U be given a higher value than 800 C. (1472 F.), the
angle will be less. Two components may be selected to suit the
resultant angle and velocity, but this cannot be intelligently done
until the pressures available for impressing velocity upon both
the gas and the air have been approximated. For the air, the
pressure available will be entirely due to the chimney effect of the
system, diminished by the resistance to the flow of the air, unless
a fan is used. The same pressure is available in the case of the
gas, plus the pressure in the gas main, which is more or less under
control through the steam blower on the producer. In order to
determine the chimney effect, it is necessary to obtain the height
of the regenerator.

In a previous chapter several empirical rules were given for the
amount of checkerwork required. According to Gruner, from
50 to 70 kg (50 to 70 Ib) of checker brick are required per kilogram
(pound) of coal burned per reversal. In the case considered,
5 m3 32 (188 cu ft) of gas is to be used each second, each kilogram
of coal producing 4 rn3 39 of gas (70 cu ft of gas per pound).
The coal consumption, therefore, is 1 kg 212 (2.686 Ib) per second.
The weight of checker brick for this amount of coal would be from
60 to 85 kg (135 to 188 Ib). According to this rule, the amount of
checker brick would be:


	50 to 1
	70 tol

For 15-min  (900-sec.) reversals    .             >
	54,540 kg
	76,360 kg

For 20-min. (12 0-sec.) reversals ........ s
	120,220 Ib 72,720 kg
	168,320 Ib 101,810 kg

For 25-rnin  (1500-sec.) reversals ....         \
	160,300 Ib 90,910 kg
	224,430 Ib 127,250 kg

	200,410 Ib
	280,550 Ib

Told suggests 6 m3 00 (212 cu ft) or 2850 kg (6283 Ib) of brick
per cubic meter (35.3 cu ft) of air per second per 100 C. (180 F.)
rise in temperature. According to this rule, the checker brick
would be
2850X8.51X9=218,250 kg (478,900 Ib)
6X8.51X9 = 459 m3 55 (16,228 cu ft)