B737电子舱和货舱冷却问题

boshao · 发表于 2014-7-21 09:25:37

请问：
1、电子舱冷却时，供气风扇的冷气来自哪里？空调组件？蒙皮外的大气？电子舱会增压吗？
2、前货舱和后货舱加温时，压力和客舱的压力一样吗？

最好能上图

bigzsu · 发表于 2014-7-21 11:04:36

请看书P303-304 （飞机结构与系统上册）

1.飞机设备冷却，电子设备仓的设备和驾驶舱的CB面板及主仪表板。
冷却介质是客舱排气。

2.货仓加温也是用客舱排气。不同机型加温加压方式不同，基本上，前货仓是恒温恒压的。后面的货仓就说不好了。

kli_08 · 发表于 2014-7-21 12:38:28

OPEN CIRCUIT CONFIGURATION
In open circuit configuration, ambient air drawn through the skin air inlet
valve by the blower fan, is blown into the system. The air, after cooling
the avionics equipment, is drawn by the extraction fan directly overboard.
The open circuit configuration allows avionics equipment to be cooled
with ambient air under certain conditions. (On ground and skin
temperature above 12°C (53,6°F) increasing, or above 9°C (48,2°F)
decreasing).
NOTE: The skin air inlet and outlet valves are fully open.

CLOSED CIRCUIT CONFIGURATION
In closed circuit configuration, the extracted avionics equipment air goes
through the skin exchanger isolation valve into the skin heat exchanger
to be cooled. Then this air is blown into the avionics equipment again.
The skin exchanger inlet bypass valve is controlled by the AEVC in
accordance to the system configuration to discharge the air under the
FWD cargo compartment. The skin exchanger outlet bypass valve opens
in order to decrease the noise level in the avionics bay.

PARTIALLY OPEN CIRCUIT CONFIGURATION
In partially open circuit configuration, the system is almost like in closed
configuration, part of the extracted air is expelled overboard.
NOTE: The skin air outlet valve is an electrically operated single flap
valve with a smaller flap built into it. This smaller flap is opened
in flight or on ground with takeoff power selected, when the
skin temperature is above 35°C (95,0°F). It returns to the closed
position when the skin temperature decreases below 31°C
(87,8°F).