The entire building is ventilated by a force or blower fan in the
basement, and by an exhaust fan in the attic with sufficient capacity to
insure complete renewal of air in each laboratory once in 20 min.
The blower fan is placed in the center of the building, on the ground
floor, and is 100 in. in diameter. Its capacity is about 30,000 cu. ft.
of air per min., and it forces the air, through a series of pipes, into
registers placed in each of the laboratories.
The exhaust fan, in the center of the attic, is run at 550 rev. per
min., and has a capacity of 22,600 cu. ft. of air per min. It draws the
air from each of the rooms below, as well as from the hoods, through a
main pipe, 48 in. in diameter.
_Steaming and Combustion Tests._--The investigations included under the
term, fuel efficiency, relate to the utilization of the various types of
fuels found in the coal and oil fields, and deal primarily with the
combustion of such fuels in gas producers, in the furnaces of steam
boilers, in locomotives, etc., and with the efficiency and utilization
of petroleum, kerosene, gasoline, etc., in internal-combustion engines.
This work is under the general direction of Mr. R. L. Fernald, and is
conducted principally in Buildings Nos. 13 (Plate XVII) and 21.
For tests of combustion of fuels purchased by the Government, the
equipment consists of two Heine, water-tube boilers, each of 210 h.p.,
set in Building No. 13. One of these boilers is equipped with a Jones
underfeed stoker, and is baffled in the regular way. At four points in
the setting, large pipes have been built into the brick wall, to permit
making observations on the temperature of the gas, and to take samples
of the gas for chemical analysis.
The other boiler is set with a plain hand-fired grate. It is baffled to
give an extra passage for the gases (Fig. 15). Through the side of this
boiler, at the rear end, the gases from the long combustion chamber
(Plate XVIII) enter and take the same course as those from the
hand-fired grate. Both the hand-fired grate and the long combustion
chamber may be operated at the same time, but it is expected that
usually only one will be in operation. A forced-draft fan has been
installed at one side of the hand-fired boiler, to provide air pressure
when coal is being burned at high capacity. This fan is also connected
in such a way as to furnish air for the long combustion chamber when
desired. A more complete description of the boilers may be found in
Professional Paper No. 48, and Bulletin No. 325 of the U.S. Geological
Survey, in which the water-measuring apparatus is also described.[13]
On account of the distance from Building No. 21 to the main group of
buildings, it was considered inadvisable to attempt to furnish steam
from Building No. 13 to Building No. 21, either for heating or power
purposes. In view, moreover, of the necessity of installing various
types and sizes of house-heating boilers, on account of tests to be made
thereon in connection with these investigations, it was decided to
install these boilers in the lower floor of Building No. 21, where they
could be utilized, not only in making the necessary tests, but in
furnishing heat and steam for the building and the chemical laboratories
therein.
[Illustration: Fig. 15.