• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    An aircraft system includes a fan, a differential pressure sensor, a temperature sensor, and a system controller. The fan provides a flow of air to at least one heat exchanger. The differential pressure sensor detects a pressure difference between a fan inlet and an outlet of the fan diffuser. The temperature sensor detects a temperature at the fan inlet. The system controller is set to receive the detected pressure difference, the detected temperature, and a fan speed, and determines a running point of the fan based further on the detected pressure difference, the fan speed, and the temperature detected. The operating point indicates the contamination of at least one heat exchanger.
    公开号:FR3014839A1
    申请号:FR1462688
    申请日:2014-12-18
    公开日:2015-06-19
    发明作者:Thomas M Zywiak；Harold W Hipsky
    申请人:Hamilton Sundstrand Corp；
    IPC主号:
    专利说明:

    [0001] BACKGROUND OF THE INVENTION The present invention relates to aircraft air-conditioning systems and in particular to a system and method for detecting the contamination of aircraft air-conditioning systems. interior of air conditioning systems. [0002] Aircraft often include air conditioning units which, among other things, provide cold air to the aircraft. These aircraft may also contain one or more dynamic air fans that draw air through the air conditioning units while the aircraft is on the ground. The dynamic air is sucked through, for example, the heat exchangers of the air conditioning units. Contamination of the ambient air can increase the pressure drop across the heat exchangers, which can reduce the flow through the fan and heat exchangers. Significant contamination of heat exchangers can reduce airflow to the point that the dynamic air fan can operate in an unstable operating mode, which can lead to excessive blade strain and then to fan failure dynamic air. SUMMARY [0003] An aircraft system includes a fan, a differential pressure sensor, a temperature sensor, and a system controller. The fan provides a flow of air to at least one heat exchanger. The differential pressure sensor detects a pressure difference between a fan inlet and an outlet of the fan diffuser. The temperature sensor detects a temperature at the fan inlet. The system controller is set to receive the detected pressure difference, the detected temperature, and a fan speed, and determines an operating point of the fan based on the detected pressure difference, the fan speed, and the temperature. detected. The operating point indicates the contamination of at least one heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS [0004] FIG. 1 is a block diagram of an aircraft air conditioning system that includes sensors for determining contamination within the air conditioning system. Figure 2 is a graph that illustrates the operating thresholds of a dynamic air fan based on the pressure difference across the fan and the fan speed. FIG. 3 is a flow diagram illustrating a method of detecting contamination inside an aircraft air-conditioning system DETAILED DESCRIPTION [0007] Contamination of heat exchangers of a Air conditioning block can be determined from an operating point of a dynamic air blower. Aircraft dynamic air fans can be used to draw air through air conditioning systems. Contamination of the heat exchangers inside the air conditioning system may result in reduced airflow through the fan and heat exchangers. This may cause the fan to operate in an unstable operating mode. The operating point of the fan is determined by the air conditioning block controller based on the pressure difference across the fan, the temperature at the fan inlet, and the speed of rotation of the fan. If the determined operating point of the fan is larger than the threshold, the block controller can reduce the fan speed to a safe operating speed and provide a maintenance indication on, for example, a maintenance bus. Figure 1 is a block diagram of the aircraft system 10 which includes sensors for determining contamination within the air conditioning block. The system 10 includes the dynamic air inlet 12, the dynamic air blower 14, the heat exchangers 16, the outlet ducts 18, the dynamic air outlet 20 and the block controller 22. Dynamic air fan 14 includes, among other things, the inlet 24, the diffuser 26, the outlet 28 and the motor 30. The motor 30 is controlled by a motor controller 32. The differential pressure sensor 34 is set to it is possible to detect a difference in pressure between the inlet 24 and the outlet of the diffuser 26. The sensor 36 is parameterized so as to be able to detect, for example, a temperature at the inlet of the fan 24. The motor 30 may be, for example, a electric motor. The motor controller 32 actuates the motor 30 and therefore knows the speed of the dynamic air fan 14. The dynamic air fan 14 can also be, for example, driven by a turbine. In this case, any conventional speed sensor, such as an optical speed sensor, can be used to determine the speed of the dynamic air fan 14. The block controller 22 can communicate with other aircraft systems using, for example, the communication bus 38. While the illustration includes three heat exchangers 16, all the numbers of the heat exchangers may be included within the system 10. In the present embodiment, Ambient air is drawn inside the heat exchangers 16 through the dynamic air inlet 12. The air passes through the heat exchangers 16 to the inlet of the fan 24. The air passes through the diffuser 26, the outlet of the fan 28, the air duct 18 and it emerges by the dynamic air outlet 20. A pressure drop can arrive through the heat exchangers 16 and can cause a reduction in the flow of air. air through the ec This pressure drop increases when the heat exchangers 16 become contaminated by the contaminants in the ambient air. The contamination of the heat exchangers 16 can reduce the flow through the dynamic air fan 14 to such an extent that the fan 14 can operate in an unstable mode. It is advantageous to detect the reduced flow caused by the contamination of the heat exchangers 16 in order to avoid unstable operating conditions of the dynamic air fan 14. [0010] The speed of the fan 14, in connection with the pressure sensor differential 34 and a temperature detected from the sensor 36, is used to detect unstable fan operating conditions created by the contamination of the heat exchangers 16. The differential pressure sensor 34 is set to be able to measure the pressure difference between the inlet of the fan 24 and an outlet of the diffuser 26. This provides a delta pressure measurement through the fan 14. [0011] By exploiting the pressure difference detected from the differential pressure sensor 34, a pressure at the Fan input 24 can be determined. The controller of the block 22 determines a flow of air through the dynamic air fan 14 by using the pressure difference detected by the sensor 34. By exploiting the determined flow as well as, for example, a known pressure drop coefficient of the outlet duct 18, the pressure drop of the outlet duct 18 can be determined. By using the determined pressure drop of the outlet duct 18, as well as the ambient air pressure, the pressure at the outlet of the blower 28 can be determined. The ambient pressure may be supplied to the block controller 22 from, for example, a static air pressure data module or other aircraft system on the communication bus 38. Using the determined pressure at the output of the fan 28 and the pressure difference determined by the sensor 34, the pressure at the inlet of the fan 24 can be determined. In another embodiment, the pressure at the inlet of the fan 24 can be directly measured by a pressure sensor. The sensor 36 may also include, for example, an integral pressure sensor or a separate pressure sensor associated with a temperature sensor. The pressure measured by the inlet pressure sensor 24 can be supplied to the controller 22. [0013] Still referring to FIG. 1, FIG. 2 is a graph illustrating the operating thresholds of the dynamic air blower 14 based on the pressure difference across the fan 14 and the fan speed 14. The Y axis reflects the pressure difference between the fan inlet 24 and an outlet diffuser 26. For more precision, the difference pressure can be divided by the ambient pressure. For even more precision, the pressure difference can be divided by the inlet pressure determined at the inlet of the fan 24. The X axis indicates the speed of the dynamic air fan 14. For greater precision, it can this is the corrected speed, which is determined by exploiting the temperature detected by the sensor 36 as well as the actual speed of the fan 14 which can be provided, for example, by the motor controller 32 or a speed sensor. The corrected speed represents the speed at which the speed fan 14 would turn if the conditions at the inlet 24 were ambient conditions at sea level. The threshold lines T1 and T2 respectively correspond to, for example, a threshold above which the fan 14 will operate in an unstable mode, and a threshold below which the fan 14 will operate in a normal mode. These thresholds can be determined, for example, by the fan test 14. These thresholds are illustrated by a range of corrected speeds between S1 and S2 which represent any of the corrected speeds of the fan 14 such as, for example, eight thousand revolutions per minute (RPM) and eleven thousand RPMs. The threshold line T2 represents the operating points of the fan 14 for which any normalized pressure difference below this value indicates that the fan 14 is operating normally for the given corrected speed. This threshold is one of the known values selected to indicate a normal operation of the fan 14 such as, for example, a margin of 30% of an overvoltage condition. The threshold line T1 indicates, for example, the operating points for which the fan 14 will operate in an unstable operating mode for all normalized pressure differences above that threshold for a given corrected speed. This threshold can be determined by, for example, a dynamic air fan test 14 and can indicate, for example, a 0% margin of an overvoltage condition. The actual threshold used to determine an unstable operating condition for which the block controller 22 will reduce the speed of the fan 14 and provide a maintenance indication may be any of the thresholds selected between, for example, the thresholds T1 and T2. While illustrated the normalization of the pressure differential using the pressure at the inlet of the fan 24, the ambient pressure can also be used to normalize the pressure difference, or the pressure difference may not be standardized at all. By normalizing the pressure difference using the inlet pressure of the fan 24, the unstable operating conditions can be more accurately predicted in some embodiments by eliminating pressure losses due to the outlet conduit 18, and pressure differences created by airports that are at varying altitudes. Once it has been determined that the current operating point has exceeded the threshold, the block controller 22 can operate the fan 14 in a safety operating mode and provide an indication on the communication bus 38 regarding the need for maintenance of the heat exchangers 16. To operate the fan 14 in a safe mode of operation, the block controller 22 may instruct the motor controller 32 to reduce the fan speed below, for example, eight thousand RPM, or any other speed for which the fan 14 can be operated without the possibility of unstable operation caused, for example, by the contamination of the heat exchangers 16. The heat exchangers can then be, for example, cleaned and maintained for the purpose of removing the contamination causing the reduced flow. Figure 3 is a flow diagram illustrating the method 50 for detecting contamination within an aircraft air conditioning system. In step 52, a pressure difference for the fan 14 is received from the differential pressure sensor 34 by the block controller 22. A temperature at the inlet of the fan 24 is received by the block controller 22 from of the sensor 36, and the speed of the fan 14 is received by the block controller 22 from the motor controller 32. In step 54, the block controller 22 determines the pressure loss of the outlet conduit 18 based on on the pressure difference detected from the sensor 34 and, for example, on a known duct loss coefficient for the duct 18. In step 56, the outlet pressure at the fan outlet 28 is determined by the block controller 22 based on the ambient pressure and the determined duct loss of the duct 18. The ambient pressure is obtained by the block controller 22 from, for example, another aircraft system on the com bus In step 58, the pressure at the inlet of the fan 24 is determined by the block controller 22 based on the pressure determined at the fan output 28 and the pressure difference detected by the fan. In one embodiment, the system 10 may include a pressure sensor at the inlet of the fan 24, wherein the steps of the cells 54 to 58 may be replaced by measuring the pressure at the fan inlet. 24 using the pressure sensor. In step 60, an operating point of the fan 14 is determined based on the pressure determined at the inlet of the fan 24, the pressure difference detected by the sensor 34 and the corrected speed of the fan 14. The corrected speed is determined by the block controller 22 based on the temperature sensed by the sensor 36 and the current speed of the fan 14 from the motor controller 32 or a speed sensor. The operating point of the fan 14 indicates a level of contamination of the heat exchangers 16. In step 62, it is determined whether the operating point of the fan 14 exceeds the threshold. The threshold can be determined through, for example, the fan test 14. This threshold indicates a contamination of the heat exchangers 16 which is large enough to create an unstable operating condition of the fan 14. If the operating point is in below the threshold, the method 50 returns to step 52. If the operating point is above the threshold, the method 50 proceeds to step 64. In step 64, the block controller 22 can indicate to the Motor controller 32 reduces the speed of the fan 14 to a safe operating speed as, for example, less than eight thousand RPM. In another embodiment, if the fan 14 is turbine driven, the controller 22 can reduce the speed of the fan 14 using any method. The controller may also provide a maintenance indication on the communication bus 38 indicating that the heat exchangers 16 need to be cleaned. Discussion of Possible Embodiments [0020] An aircraft system includes, among other things: a fan, a differential pressure sensor, a temperature sensor, and a system controller. The fan provides a flow of air to at least one heat exchanger. The differential pressure sensor detects a pressure difference between a fan inlet and an outlet of the fan diffuser. The temperature sensor detects a temperature at the fan inlet. The system controller is set to receive the detected pressure difference, the detected temperature, and a fan speed, and determines a fan operating point based on the detected pressure difference, fan speed, and temperature. detected. The operating point indicates the contamination of at least one of the heat exchangers. The aircraft system of the preceding paragraph may optionally include, in addition and / or alternatively, one or more of the following features, configurations and / or additional components: [0022] Another embodiment of the previous system, wherein the system controller determines a flow through the fan based on the detected pressure difference, and wherein the system controller determines a loss of pressure of the output conduit based on the determined flow. Another embodiment of any of the foregoing systems, wherein the system controller determines a fan output pressure based on the determined pressure loss of the output conduit, and wherein the controller of The system determines a fan inlet pressure based on the determined output pressure and the detected pressure differential. Another embodiment of any of the foregoing systems, wherein the system controller determines the operating point of the fan further based on the determined input pressure of the fan. Another embodiment of any one of the foregoing systems, further comprising a pressure sensor which measures a fan input pressure, wherein the system controller determines the operating point of the fan based on furthermore on the measured inlet pressure of the fan. Another embodiment of any of the foregoing systems, wherein the system controller reduces the fan speed when the determined operating point of the fan reaches a threshold. Another embodiment of any of the foregoing systems, wherein the system controller provides a maintenance indication on a communication bus when the determined operating point of the fan reaches the threshold. Another embodiment of any of the foregoing systems, further comprising a motor controller that drives the fan, wherein the fan speed is supplied to the system controller from the motor controller. Another embodiment of any of the foregoing systems, further comprising a speed sensor, wherein the fan is driven by turbine and the speed sensor provides the fan speed to the system controller. A method for detecting the contamination of at least one heat exchanger in an aircraft system which comprises, among other things: the detection, by a differential pressure sensor, of a pressure differential between an inlet a fan and an outlet of a fan diffuser; detecting, by a temperature sensor, an inlet temperature at the fan inlet; the detected pressure differential and the detected input temperature supplied to the system controller; and determining, by the system controller, an operating point of the ventilator based on the detected pressure differential, a fan speed and the detected input temperature, wherein the operating point of the fan indicates the contamination of at least one heat exchanger. The method of the preceding paragraph may optionally include, in addition and / or alternatively, one or more of the following features, configurations and / or additional components: [0032] Another embodiment of the preceding method, which includes in furthermore: determining, by the system controller, a flow through the fan based on the detected pressure differential; determining, by the system controller, a loss of duct pressure of the outlet duct, wherein the outlet duct is connected between a fan outlet and the ambient air; determining, by the system controller, an outlet pressure at the fan outlet based on the loss of duct pressure and ambient ambient air pressure; and determining, by the system controller, an inlet pressure at the fan inlet based on the determined output pressure and the detected pressure differential, wherein the determination of the operating point of the fan is further based on the determined inlet pressure. Another embodiment of any one of the preceding methods, further comprising measuring an inlet pressure at the fan inlet using an inlet pressure sensor, wherein the determination of the operating point of the fan is also based on the measured inlet pressure. Another embodiment of any of the foregoing methods, further comprising reducing the fan speed using the system controller if the determined operating point of the fan exceeds a threshold; and wherein a maintenance indication is provided using the system controller if the determined operating point of the fan exceeds the threshold. Another embodiment of any of the foregoing methods, further comprising the fan speed supplied to the system controller from the motor controller, wherein the motor controller controls the fan speed. Another embodiment of any of the foregoing methods, further comprising the fan speed supplied to the system controller from the speed sensor, wherein the fan is driven by turbine and the control system controller the speed of the fan. While the invention has been described with reference to a mode (s) of exemplary embodiment (s), those skilled in the art will understand that several changes can be made and that elements can be replaced by other equivalents without this outside the scope of the invention. In addition, many modifications can be made to adapt a particular situation or a particular material to the teachings of the invention without it being outside the main objective of the invention. Therefore, it is intended that the invention is not limited to the embodiment (s) described, but that the invention includes all embodiments that fall within the scope of the appended claims.
    权利要求:
    Claims (8)
    [0001]
    CLAIMS: 1. An aircraft system comprising: a fan that provides a flow of air to at least one heat exchanger; a differential pressure sensor which detects a pressure difference between a fan inlet and an outlet of the diffuser; and a temperature sensor that detects a temperature at the fan inlet; and a system controller set to receive the detected pressure difference, the detected temperature, and a fan speed, wherein the system controller determines a running point of the fan based on the detected pressure difference, the speed of the fan, and fan and the temperature detected, and wherein the operating point indicates the contamination of at least one heat exchanger.
    [0002]
    The aircraft system of claim 1, further comprising an output conduit connected between a fan output and the ambient air, wherein the system controller determines a flow through the fan based on the difference in detected pressure, and wherein the system controller determines a loss of pressure of the output conduit based on the determined flow.
    [0003]
    The aircraft system of claim 2, wherein the system controller determines a fan output pressure based on the determined pressure loss of the output conduit, and wherein the system controller determines a pressure of fan input based on the determined output pressure and the detected pressure differential.
    [0004]
    The aircraft system of claim 3, wherein the system controller determines the operating point of the fan based further on the determined input pressure of the fan.
    [0005]
    The aircraft system of claim 1, further comprising a pressure sensor which measures a fan inlet pressure, wherein the system controller determines the operating point of the fan further based on the pressure of the fan. measured input of the fan.
    [0006]
    The aircraft system of any one of claims 1 to 5, wherein the system controller reduces the fan speed when the determined operating point of the fan reaches a threshold.
    [0007]
    The aircraft system of claim 6, wherein the system controller further provides a maintenance indication on a communication bus when the determined operating point of the fan reaches the threshold.
    [0008]
    The aircraft system of any one of claims 1 to 7, further comprising a motor controller that drives the fan, wherein the fan speed is supplied to the system controller from the engine controller. An aircraft according to any one of claims 1 to 8, further comprising a speed sensor, wherein the fan is driven by turbine and the speed sensor provides the fan speed to the system controller. A method for detecting the contamination of at least one heat exchanger in an aircraft system, the method comprising: detecting, by a differential pressure sensor, a pressure differential between a fan inlet and a outlet of the fan diffuser; detecting, by a temperature sensor, an inlet temperature at the fan inlet; supplying the detected pressure differential and the detected input temperature to a system controller; and determining, by a system controller, an operating point of the fan further based on the determined pressure differential, a fan speed and the detected input temperature, wherein the fan operating point indicates the contamination of at least one heat exchanger. The method of claim 10, further comprising: determining by the system controller a flow through the fan based on the detected pressure differential; determining, by the system controller, a loss of duct pressure of an outlet duct, wherein the outlet duct is connected between an outlet of the blower and the ambient air; determining, by the system controller, an outlet pressure at the fan outlet based on the loss of duct pressure and ambient ambient air pressure; and determining, by the system controller, an inlet pressure at the fan inlet based on the determined output pressure and the detected pressure differential, wherein the determination of the operating point of the fan is further based on the determined inlet pressure. The method of claim 10, further comprising measuring an input pressure at the fan inlet using an input pressure sensor, wherein the determination of the operating point of the fan is further based on the measured inlet pressure. The method of any one of claims 10 to 12, further comprising: reducing the fan speed using the system controller if the determined operating point of the fan exceeds a threshold; and providing a maintenance indication using the system controller if the determined operating point of the fan exceeds the threshold. The method of any of claims 10 to 13, further comprising providing the fan speed to the system controller from the motor controller, wherein the motor controller controls the fan speed. any one of claims 10 to 14, further comprising providing the fan speed to the system controller from a speed sensor, wherein the fan is turbine driven and the system controller controls the speed of the fan. 5 fan.
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    同族专利:
    公开号 | 公开日
    US20150166186A1|2015-06-18|
    US9862495B2|2018-01-09|
    FR3014839B1|2017-11-24|
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    法律状态:
    2015-11-23| PLFP| Fee payment|Year of fee payment: 2 |
    2016-11-21| PLFP| Fee payment|Year of fee payment: 3 |
    2017-04-14| PLSC| Publication of the preliminary search report|Effective date: 20170414 |
    2017-11-21| PLFP| Fee payment|Year of fee payment: 4 |
    2019-11-20| PLFP| Fee payment|Year of fee payment: 6 |
    2020-11-20| PLFP| Fee payment|Year of fee payment: 7 |
    2021-11-18| PLFP| Fee payment|Year of fee payment: 8 |
    优先权:
    申请号 | 申请日 | 专利标题
    US14/132,973|US9862495B2|2013-12-18|2013-12-18|Aircraft air-conditioning heat exchanger contamination detection|
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