CN217233837U

CN217233837U - Bidirectional injection anti-surge and flow-stabilizing fan exhaust device

Info

Publication number: CN217233837U
Application number: CN202123423961.8U
Authority: CN
Inventors: 马慧才; 李荣军; 王巍
Original assignee: AVIC First Aircraft Institute
Current assignee: AVIC First Aircraft Institute
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-08-19
Anticipated expiration: 2031-12-31

Abstract

The application belongs to the field of aviation environment control system design, and particularly relates to a bidirectional injection anti-surge and flow-stabilizing fan exhaust device. The method comprises the following steps: an exhaust casing, a fairing, and a ram outlet section. A first air flow channel is arranged inside the exhaust device shell, a stamping inlet is formed in the bottom of the exhaust device shell, and a stamping outlet is formed in the outlet end of the exhaust device shell; the fairing is arranged in the first airflow channel, a second airflow channel is arranged inside the fairing, and a fan of the air cycle machine is arranged in the second airflow channel; the stamping outlet section is arranged in the first airflow channel and located at the downstream of the fairing, an injection seam is arranged between the inlet end of the stamping outlet section and the outlet end of the fairing, the outlet end of the stamping outlet section is fixedly installed at the stamping outlet of the exhaust device shell, and a third airflow channel is arranged inside the stamping outlet section. The application can avoid the adverse effect caused by the overspeed and the surge of the fan.

Description

Bidirectional injection anti-surge and flow-stabilizing fan exhaust device

Technical Field

The application belongs to the field of aviation environment control system design, and particularly relates to a bidirectional injection anti-surge and flow-stabilizing fan exhaust device.

Background

The environment control system is used as a high energy consumption system in a large airplane, mainly ensures the safety and comfort of airplane passengers and passengers, and provides normal working environment conditions for onboard electronic equipment. The refrigeration system is a key subsystem of an Environmental Control System (ECS), and the aircraft mainly adopts an air circulation refrigeration system using air as a circulation medium, and mainly comprises an air circulator for cooling high-temperature and high-pressure air, such as a coaxial fan, a turbine and a compressor, a valve for adjusting temperature and flow, and a heat exchanger for discharging heat outside the aircraft.

The essence of the working process of the aircraft refrigeration system is energy transfer, and the conventional aircraft refrigeration system dissipates the energy carried by high-temperature and high-pressure gas from an engine into the external atmosphere through heat dissipation of a radiator, so that the temperature of supplied air is reduced to a proper range and is supplied to a cabin, and the energy of air with higher temperature in the cabin is absorbed, thereby realizing the refrigeration function of the aircraft cabin. The temperature of an air circulation refrigeration system adopted by an airplane is automatically controlled, the condition that the mass flow of the ram air on the cold edge of a radiator is low or high can be involved in the temperature regulation process, and the reason for the phenomenon is two: 1. an actuating mechanism is arranged in the ram air channel to reduce the mass flow of ram air so as to achieve the purpose of increasing the outlet temperature of the refrigeration assembly; 2. the high atmospheric density is much lower than the ground and therefore the mass flow rate may still be in a lower range even though ram air maximum capacity is fed into the assembly. When the refrigerating system adopts a T-F (turbo-fan type), a T-C-F (turbo-compressor-fan type) and a T-T-C-F (turbo-compressor-fan type) configuration, the cold-side ram air quality of the radiator is determined by the suction capacity of the fan, and when the mass flow of the cold-side ram air is low, the fan enters a surge area, namely: the separation area of the fan is continuously enlarged, most of the passages of the blades are in a vortex area, airflow flowing into the blades is instantaneously interrupted, gas can flow back from an outlet to an inlet from the separated vortex area, meanwhile, because the counter pressure gradient disappears, the air enters the turbine again and is separated and flows back again, the phenomenon is continuously carried out at a low frequency to form surging, the airflow is violently vibrated, the strong vibration of the blades is caused, the phenomenon can cause the impeller to be subjected to great dynamic stress, the impeller to generate strong vibration, the impeller can be damaged in a short time, and therefore the air cycle machine is not allowed to work in a surge state. 3. Only when the aircraft speed improves to certain extent, the dynamic pressure is higher than the sum of fan suction capacity and ram air flow channel internal flow resistance, and the radiator cold edge ram air mass flow is higher than normal and can lead to another extreme phenomenon: the air flow through the fan exceeds the fan load capacity and the fan speed will increase and maintaining the fan at a higher speed for a period of time will result in damage to the air cycle machine.

Accordingly, a technical solution is desired to overcome or at least alleviate at least one of the above-mentioned drawbacks of the prior art.

SUMMERY OF THE UTILITY MODEL

The application aims to provide a bidirectional ejection anti-surge and flow-stabilizing fan exhaust device to solve at least one problem in the prior art.

The technical scheme of the application is as follows:

a bidirectional ejection anti-surge and flow-stabilizing fan exhaust device comprises:

the exhaust device is an integral structure consisting of an exhaust device shell, a fairing and a stamping outlet section, an injection seam is arranged in the exhaust device, and a fan of the air circulator is fixedly arranged in the fairing in a mechanical mode;

the inner part of the exhaust device shell is provided with a first air flow channel, the bottom of the exhaust device shell is provided with a stamping inlet, the outlet end of the exhaust device shell is provided with a stamping outlet, external stamping air enters from the inlet, and the stamping air is discharged to a stamping outlet section from the inlet under the suction action of a fan;

the fairing is arranged in the first airflow channel, a second airflow channel is arranged inside the fairing, and a fan of the air cycle machine is fixedly arranged in the second airflow channel in a mechanical mode;

the stamping outlet section is arranged in the first air flow channel and is positioned at the downstream of the fairing, the injection gap is arranged between the inlet end of the stamping outlet section and the outlet end of the fairing, the outlet end of the stamping outlet section is fixedly arranged at the stamping outlet of the exhaust device shell, and a third air flow channel is arranged inside the stamping outlet section.

In at least one embodiment of the present application, the outlet end of the fairing is convergent.

In at least one embodiment of the present application, the inlet end of the ramjet section is convergent and the outlet end is divergent, and the inlet end of the ramjet section has a profile area greater than the outlet end of the fairing.

In at least one embodiment of the present application, the air cycle machine to which it is connected is a fan, a turbine, and a compressor that are coaxially disposed.

Utility model has the following beneficial technical effects:

the two-way ejection anti-surge and flow-stabilizing fan exhaust device can avoid the adverse effects caused by overspeed and surge of the fan, and ensures the safety and stability of system operation.

Drawings

Fig. 1 is a two-way injection anti-surge flow stabilizing fan exhaust device according to an embodiment of the present application.

Wherein:

1-an exhaust housing; 2-a fairing; 3-punching an outlet section; 4-a fan; 5-injection seam.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described are some, but not all embodiments of the disclosure. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application. Embodiments of the present application will be described in detail below with reference to the accompanying drawings.

In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience in describing the present application and for simplifying the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be construed as limiting the scope of the present application.

The present application is described in further detail below with reference to fig. 1.

The application provides a two-way injection prevents breathing heavily stationary flow fan exhaust apparatus includes: exhaust apparatus casing 1, radome fairing 2 and punching press export section 3, exhaust apparatus is the overall structure who comprises exhaust apparatus casing 1, radome fairing 2, punching press export section 3, and inside is provided with penetrates seam 5, and exhaust apparatus and air cycle machine's fan 4 is fixed through mechanical system.

A first air flow channel is arranged inside the exhaust device shell 1, the bottom of the exhaust device shell 1 is provided with a stamping inlet, and the outlet end of the exhaust device shell 1 is provided with a stamping outlet; for ambient ram air to enter from the inlet, which is discharged from the inlet to the ram outlet section 3 by the suction effect of the fan 4. The cowling 2 is arranged in a first air flow channel, and a second air flow channel is arranged inside the cowling 2, in which second air flow channel the fan 4 of the air cycle machine is fixedly mounted by mechanical means.

The punching outlet section 3 is arranged in the first air flow channel and is positioned at the downstream of the fairing 2, an injection gap 5 is arranged between the inlet end of the punching outlet section 3 and the outlet end of the fairing 2, the outlet end of the punching outlet section 3 is fixedly arranged at the punching outlet of the exhaust device shell 1, and a third air flow channel is arranged inside the punching outlet section 3.

In the preferred embodiment of the present application, the outlet end of the fairing 2 is convergent, the inlet end of the ram-outlet section 3 is convergent, the outlet end is divergent, and the inlet end of the ram-outlet section 3 has a larger profile area than the outlet end of the fairing 2.

In the preferred embodiment of the present application, the air cycle machine includes a fan 4, a turbine, and a compressor, which are coaxially disposed.

In operation of the air circulation refrigeration system ram air flows through the radiator block and enters the exhaust through the ram inlet of the exhaust housing 1. In a ground state, the realization of the refrigeration capacity of the air conditioner is mainly realized by sucking ambient air through a fan 4 of the air cycle machine, all the air enters the fairing 2 through the fan end of the air cycle machine and is further continuously discharged through the punching outlet section 3, and the quality of the punching air at the cold edge of the radiator is improved; in the air state, because of the ram action of the outside air, the fan 4 of the air cycle machine does not play a role in sucking the ambient air any more, and as the flying speed is increased, the total ram air flow entering the air duct is larger than the circulation capacity of the fan end, and the speed of the fan needs to be increased. When the ram air flow entering the scheduling device is larger than the maximum flow of a given fan at the working rotating speed, redundant fluid should be discharged through structural design, and effective matching of the fan and a pipeline system is guaranteed, so that the problem of turbine overspeed is solved.

According to the two-way injection anti-surge and flow-stabilizing fan exhaust device, the injection gap 5 is additionally arranged between the inlet end of the stamping outlet section 3 of the fan exhaust device and the outlet end of the fairing 2, when the flow is overlarge, the pressure rise of the fan 4 of the air circulating machine is low, the outlet flow speed is higher than the inlet flow speed, the dynamic pressure inside the injection gap 5 is lower than that outside the injection gap, and therefore an air bypass can flow into the injection gap 5 and then is exhausted from the stamping outlet section 3 of the fan exhaust device, stamping air bypasses the fan, and the phenomenon that overlarge stamping air flow enters the fan end to cause the overspeed of the bleed fan is avoided; when the flow is too small, the pressure rise of the fan 4 is high, the outlet flow speed is lower than the inlet flow speed, and the dynamic pressure inside the injection slit 5 is higher than that outside the injection slit 5, so that an air bypass can flow out of the exhaust device through the injection slit 5 and flows back to the inlet of the fan 4 of the air cycle machine along with the pressure gradient, and the phenomenon that the too small ram air flow enters the bleed air fan at the fan end to cause surging is avoided; therefore, the bidirectional injection anti-surge and flow-stabilizing fan exhaust device can avoid the adverse effects caused by the overspeed and surge of the fan and ensure the safe and stable operation of the system.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a two-way injection prevents breathing heavily stationary flow fan exhaust apparatus which characterized in that includes:

the exhaust device is an integral structure consisting of an exhaust device shell (1), a fairing (2) and a punching outlet section (3), an injection seam (5) is arranged in the exhaust device, and a fan (4) of the air circulator is fixedly arranged in the fairing (2) in a mechanical mode;

a first air flow channel is arranged in the exhaust device shell (1), a stamping inlet is formed in the bottom of the exhaust device shell (1), a stamping outlet is formed in the outlet end of the exhaust device shell (1) for external stamping air to enter from the inlet, and the stamping air is discharged from the inlet to the stamping outlet section (3) through the suction effect of the fan (4);

the fairing (2) is arranged in the first airflow channel, a second airflow channel is arranged inside the fairing (2), and a fan (4) of the air cycle machine is fixedly arranged in the second airflow channel in a mechanical mode;

the stamping outlet section (3) is arranged in the first air flow channel and located at the downstream of the fairing (2), the injection gap (5) is arranged between the inlet end of the stamping outlet section (3) and the outlet end of the fairing (2), the outlet end of the stamping outlet section (3) is fixedly installed at a stamping outlet of the exhaust device shell (1), and a third air flow channel is arranged inside the stamping outlet section (3).

2. The exhaust device of the bidirectional ejection anti-surge flow-stabilizing fan as claimed in claim 1, wherein the outlet end of the cowling (2) is convergent.

3. The exhaust device of the bidirectional injection anti-surge flow-stabilizing fan as claimed in claim 2, wherein the inlet end of the ram outlet section (3) is convergent, the outlet end is divergent, and the profile area of the inlet end of the ram outlet section (3) is larger than that of the outlet end of the fairing (2).

4. The exhaust device of the bidirectional injection anti-surge and flow-stabilizing fan as claimed in claim 1, wherein the air circulator is connected with a fan (4), a turbine and a compressor which are coaxially arranged.