Publish Time: 2022-07-15 Origin: Site
Since the end of the ground air-conditioning pipeline at the airport is in direct contact with the aircraft, its connection with the aircraft, the temperature of the cold air at the end of the ground air-conditioning and other state quantities are important parameters related to the safety of aircraft operation and the feedback adjustment of equipment. At present, civil aviation the airport does not have a system for monitoring and alarming the status of the end of the air-conditioning pipeline on the ground of the airport; when the air-conditioning pipeline on the ground is connected to the aircraft, some airports will arrange for ground staff to check the end of the pipeline every hour. Whether there is a tripping phenomenon (that is, the air duct joint), and at the same time, check whether the temperature of the cold air delivered by the end of the ground air conditioning pipeline of the airport aircraft is normal. The requirement of real-time and accurate monitoring and alarming of the above parameters leaves hidden dangers to aviation safety and affects the service evaluation of the airport, and at the same time causes waste of human resources. Therefore, a new technical solution is needed to replace the traditional manual inspection method in the prior art, so as to meet the current needs of efficient utilization of resources, and at the same time improve the safety and reliability of the equipment.
Aircraft ground air conditioning (hereinafter referred to as PCA) is an air conditioning unit that provides fresh air suitable for temperature and humidity environment and physiological needs for passengers and crew members parked on the boarding bridge at the airport, which provides a comfortable environment during ground maintenance. The unit has the characteristics of rapid cooling, fresh air, and large air volume. Replacing the aircraft APU system when the aircraft is ready to fly or maintain on the ground can greatly reduce the cost and reduce the pollution to the airport environment. It has the characteristics of energy saving and environmental protection. After the official opening of the PCA of Baiyun Airport Terminal 2, it can avoid the pollution caused by the consumption of aviation kerosene by the aircraft APU, reduce carbon dioxide emissions every year, and also reduce the operating time and frequency of aircraft engines, thereby saving aircraft operating costs. Extend the service life of the aircraft's own air conditioning system and engine.
The aircraft ground air conditioning unit is an integral design. The unit mainly includes scroll compressor, evaporator, condenser, gas-liquid separator, axial flow fan, blower, PTC electric heating, air valve and other components. The PCA unit is installed under a passenger boarding bridge (PBB) immediately behind the vertical lift column, and the air conditioning unit is connected to the PBB by 4 hooks. The air delivery hose is attached to the outlet of the air conditioning unit and hangs down into the duct trolley located below.
After the aircraft air conditioner is started, the host refrigeration unit sends the cold air into the aircraft cabin through the air supply hose, and connects the air duct inlet at the bottom of the aircraft in the form of a snap.
Provide a comfortable cabin environment for passengers and crew members, implement the civil aviation blue sky defense war and build a green airport. After the aircraft is parked on the ground, the engine must be turned off and the ground equipment must be used. When the aircraft ground air conditioner is in use, the air duct joint of the air conditioner is connected to the cooling pipe of the aircraft through the clip. However, during the connection process, the clip is deformed or clipped. When the connection is not in place, when the air conditioner delivers the cold air to the aircraft, the air supply volume of the air conditioner can reach 12000m3/h, and the air duct joint will fall off under the impact of high air volume and pressure, and the aircraft will be damaged when the air duct joint falls. In order to allow passengers and crew members to use the aircraft air conditioner with more confidence, this plan proposes a decoupling detection device for the air duct head of the aircraft air conditioner. In this way, safety accidents can be avoided, and passengers can be more assured, at ease and comfortable.
1. When the air duct head falls off, trigger the detection device to stop the air conditioner to avoid damage to the aircraft or ground support personnel when the air duct head falls off;
2. The air duct head is equipped with a DS18B20 temperature sensor, which can collect the temperature on the aircraft;
3. Through the 485 interface, the background can collect the current status information of the air duct head and feed it back to the management system to achieve real-time monitoring.
4. The principle of the decoupling device for the duct head:
(1) Detect the function of the sender:
a.Temperature data detection: The DS18B20 temperature sensor is used. When the air conditioner is working, the temperature data of the air duct head is detected in real time and sent back to the receiving end.
b. Falling off state detection: The mercury tilt switch is used. When the air duct head falls off, the mercury is triggered under the condition of gravitational acceleration, and a falling off state is detected. After the mercury switch is turned on, the state signal is sent to the receiving end to control the action of the relay.
c. Dormancy mechanism: When the air conditioner is working, the sender will start to work after receiving the start signal of the air conditioner blower for 5 seconds. When the air conditioner is not working, the sender will be in a dormant state. Avoid draining battery power when not working.
d. Power supply requirements: The battery capacity can be used for at least 2 years.
e. Requirements for fixed-point transmission: It should be considered that the drop-off signal of the current transmitting end on site will not affect the working state of adjacent equipment. The sender can be set to match with the receiver, and the matching effect is that one receiver can correspond to one or two senders.
f. The communication distance between the sender and the receiver (closed space) is more than 50 meters.
The temperature sensor, mercury switch, battery and signal transmitter are integrated into the air duct head.
(2) Receiver interface description
a. Power interface: 8~28V
b. Communication interface: RS485, used to output temperature data and status signals, and paired debugging of modules.
c. Relay output interface: normally open end, common end, normally closed end
d. Switch interface: the air conditioner switch signal input terminal (if the input is a high and low level signal, the voltage cannot exceed 5V), the line is closed, and the signal detection of the acquisition terminal is started; the line is disconnected, and the signal detection of the acquisition terminal is closed.
When the receiver device is powered on and works normally, turn on the air conditioner (air conditioner switch signal is closed), and activate the sender device; after receiving the activation command, the sender device reports the current temperature and status signal, and reports temperature data every 10 minutes; When the sender device detects that the air duct head has fallen off, it immediately reports the current temperature and status signal; the receiver device detects the status signal, turns on the relay to work for 20 seconds, and sends a sleep command to the sender. After 20 seconds, the relay status is restored.
A sensor is installed on the air duct joint of the modified aircraft ground air conditioning to detect the state of the end of the air duct. The processor processes and converts the signal transmitted from the sensor and uploads it to the terminal actuator to realize the state detection of the air duct joint of the aircraft ground air conditioning, instead of The traditional manual inspection method in the existing technology meets the current needs of efficient utilization of resources. It has the function of monitoring the terminal status and connection status of the aircraft air-conditioning air duct, and can be wirelessly transmitted back to the aircraft air-conditioning host in real time, which is applied to the real-time performance of aircraft air-conditioning Feedback adjustment and duct joint trip monitoring. The air transport industry is playing an increasingly important role in the modern logistics industry. Ensuring the effectiveness of its operation and maintenance work to the greatest extent will be directly related to the safety and efficiency of this industry. This transformation will ensure the maximum extent of the aircraft The safety of the ground air conditioning operation avoids the waste of human resources, time resources and money resources, and provides convenience for the maintenance of airport order and passenger service.