18A1. Air distribution diagram. The arrangement of the air duets throughout a
submarine is shown in Figure 18-1, inserted at
the back of the book. The diagram is largely
self-explanatory and needs no detailed description.
Note the location of the two air-conditioning
coolers, or evaporators, in the crew's quarters
and the after machinery compartment. The
cooling coils are readily accessible for cleaning. The compressors are located in the pump
Part of the system is a suction main that
exhausts fumes and used air, and part is a
pressure main through which fresh or conditioned air is blown into the compartments.
Small arrows on Figure 18-1 indicate the
direction of air flow in these ducts;
Dampers, located at most of the inlet and
exhaust points of the ducts, are manually set
to control the rate of air flow into and out of
the rooms at such points.
18A2. Insulation of ducts. The supply air
ducts are insulated to prevent heat gain during
passage of the newly conditioned air to the
rooms. The supply ducts in the engine room
and the supply ducts from the discharge side
of the forward air-conditioning cooler to the
after bulkhead of the forward torpedo room
are provided with 1/2-inch insulation. All other
mains and branch ducts are cork painted.
18A3. Fans. Four motor-driven suction fans
in the exhaust main, two in the officer's quarters, and two in the crew's messroom, each
pull air at the rate of 500 cubic feet per minute. Their main purpose is battery ventilation,
but the suction created in the duct is sufficient
to provide some degree of exhaust from the
galley, scullery, showers, water closets, and
other parts of the forward and after battery
The submarine ventilation supply is provided by one motor-driven fan, located in the
forward machinery compartment, that delivers
air through the two evaporators, or air-conditioning coolers, to the various room outlets of
the ducts at the maximum rate of 4,000 cubic
feet per minute. The exhaust ventilation
through air ducts is provided by another
motor-driven fan located in the forward machinery compartment. This forced exhaust
ventilation through ducts is not provided in
the after torpedo room and maneuvering room,
from which exhaust air flows through bulkhead ventilators. The individual rates at which
the air is exhausted and delivered in the
various compartments is shown in Figure 18-1.
18A4. Ventilation data. The following table
shows, for each room, or compartment, the net
volume in cubic feet, the air supplied in cubic
feet per minute, and the number of minutes
required to change the air in the room.
NET VOL. CU. FT.
AIR SUPPLIED CFM
MIN. TO CHANGE
For'd. Torpedo Room
Officers' W.C. in For'd. Torpedo Room
Crew's Mess Room and Galley
Main Magazine Compartments
Normal Storeroom or Spec. 4-In. Mag.
Crew's W. C.'s
Forward Machinery Compartment
Aft Machinery Compartment
W.C. in Maneuvering Room
Aft Torpedo Room
* Includes natural supply from other compartments as well as direct mechanical supply from main.
** Includes 2560 cfm discharge from ship's exhaust ventilator set as well as direct mechanical supply from main.
18B1. Handling of the air duct system.
Under various conditions while running on the
surface or submerged, it is necessary to set
certain main dampers that close, open, or
partly close the main air ducts, to open or
close the outboard hull valves, and to operate
or stop the compressors. In Figure 18-1, the
following letters are used to identify and locate
these valves and, dampers .(the same letters
are used in the Key and in the Table of Operating Conditions):
Main engine air induction valve
Ventilation supply hull valve
3. D and E
Engine induction hull valves
4. F and G
Dampers in the cross-connection between the supply and exhaust blowers