JP2006213168A - Vertical taking-off and landing aircraft, and engine controller for vertical taking-off and landing aircraft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for realizing weight reduction and improvement in fuel consumption. <P>SOLUTION: The vertical taking-off and landing aircraft is provided with two gas turbine engines, two bleed air flow passages in which compressed air discharged from each gas turbine engine is circulated, two check valves provided to each bleed air flow passage, an aggregate air flow passage in which the compressed air circulated in the two bleed air flow passages is circulated by aggregating the compressed air at the downstream side of each check valve, a thrust generating means for generating thrust by utilizing the compressed air circulated in the aggregate air flow passage, a flow rate control means for controlling an amount of the compressed air utilized for generating the thrust by the thrust generating means, and a thrust control means for controlling the thrust generated by the thrust generating means by controlling the flow rate control means. The engine controller controls one of the two engines of the vertical taking-off and landing aircraft. When the other engine fails to operate properly, output of 130% of the maximum rated output is set as the maximum output. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vertical take-off and landing aircraft equipped with two gas turbine engines and an engine control device thereof.

  Patent Document 1 proposes a technique in which, when an engine failure is detected in a two-free turbine engine helicopter, the engine operation impossibility limit of the remaining engine is increased according to the output of the failed engine.

  In the helicopter that obtains thrust with two engines, in consideration of safety at the time of engine failure, even if one engine fails, the other one can continue to fly, and the engine output Is selected so that even one unit will not interfere with the operation of the aircraft.

Therefore, in a state where the engine does not fail, the required output of the aircraft is supplied by two engines, so that the output per engine is inevitably operated in a low output state.
JP-T 8-502805 JP 58-214499 A

  Gas turbine engines have the characteristic that fuel efficiency deteriorates when operated in a low output state. In general, the higher the cycle temperature represented by the turbine inlet temperature, the higher the thermal efficiency and the higher the output of the gas turbine engine. Therefore, the engine has a rated rotational speed and the cycle temperature is the allowable maximum temperature. At such a rated output point, the output and fuel consumption are good.

  Therefore, when the gas turbine engine is operated in a low output state, the cycle temperature is lowered, and the fuel efficiency is deteriorated. Therefore, as a vertical take-off and landing aircraft equipped with two gas turbine engines, it is necessary to improve the fuel efficiency in the low engine output state when the two engines are operated.

  In addition, the weight of the engine increases with increasing output. Therefore, as the engine with a large surplus output is installed, the weight of the fuselage increases and the required engine output increases accordingly, so that the fuel consumption is further deteriorated.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a technique capable of reducing weight and improving fuel consumption.

In order to achieve the above object, in a vertical take-off and landing aircraft according to the present invention, two gas turbine engines, two bleed air passages through which compressed air discharged from each gas turbine engine circulates, Two check valves provided in the air flow path, a collective air flow path for collecting and flowing the compressed air that has flowed through the two extraction flow paths downstream, and flowing through the collective air flow path A thrust generating means for generating thrust using the compressed air, a flow rate control means for controlling the amount of compressed air used for thrust generation by the thrust generating means, and controlling each gas turbine engine Two engine control means, and thrust control means for controlling the flow rate control means to control the thrust generated by the thrust generation means.

  In the vertical take-off and landing aircraft configured as described above, the thrust generating means generates thrust using compressed air that is discharged from the gas turbine engine and flows through the extraction flow passage and the collection air passage. The control means controls the flow rate control means to control the thrust generated by the thrust generation means. In the vertical take-off and landing aircraft, two engines are mounted on the assumption that the engine will fail, and the compressed air from both engines is used evenly. A check valve is provided in each bleed passage to prevent the compressed air from the two engines from interfering with each other.

  As described above, since the thrust generating means generates thrust using the compressed air discharged from the gas turbine engine, the gas turbine engine and the thrust generating means are connected only by an air flow path such as an extraction flow path. Can do. Therefore, the arrangement of the thrust generation means can be freely set as compared with the case where the gas turbine engine and the thrust generation means are mechanically connected. In addition, since the number, size, etc. of the thrust generating means can be freely set according to the size of the flying object, this also increases the degree of freedom in arranging the thrust generating means. As a result, the vertical take-off and landing aircraft can be made compact and lightweight, and fuel consumption can be improved.

  In the above configuration, it is preferable that the apparatus further includes a pressure fluctuation suppressing unit that suppresses a pressure fluctuation of the compressed air that has flowed into the collective air flow path from the two extraction flow paths. As a result, the amount of compressed air that reaches the thrust generating means from the aggregated air flow path can be controlled with high accuracy, so that the thrust can be controlled with high accuracy.

  In the engine control apparatus according to the present invention, two gas turbine engines, two extraction passages through which compressed air discharged from each gas turbine engine flows, and each extraction passage are provided. Utilizing two check valves, a collective air flow for collecting and flowing compressed air that has flowed through the two extraction flow channels downstream of the check valve, and a compressed air that has flowed through the collective air flow path A thrust generating means for generating thrust, a flow rate control means for controlling the amount of compressed air used for thrust generation by the thrust generating means, and a thrust generating means for controlling the flow rate control means. An engine control device for controlling one of the two engines of the vertical take-off and landing aircraft, the thrust control means for controlling the generated thrust, and when the other engine fails, the maximum Characterized by a 130% of the output of the rated output and maximum output.

  In the vertical take-off and landing aircraft, assuming that the engine will break down, two engines will be installed. However, in such a vertical take-off and landing aircraft, the output is originally generated to meet the required output of the aircraft. Therefore, when the two engines are normal and the two engines supply the output required by the aircraft, each engine will inevitably have to perform partial load operation. .

  Originally, the engine output of a relatively large vertical take-off and landing aircraft such as a helicopter is selected so that even one engine can continue to fly to some extent. Therefore, when the vertical take-off and landing aircraft flies with one engine, the maximum rated output is the highest output required for that engine.

  And when both engines are normal and the output required by the fuselage is supplied by two engines, the maximum output per engine is 50% of the maximum rated output, and the fuel efficiency in that case is 100% output. It becomes worse than time.

  On the other hand, as described above, if the vertical take-off and landing aircraft can be made compact and landing is possible even in a relatively small space, and it can be landed at an early stage even in an emergency where one engine breaks down, There is no need to allow much extra engine output.

  Therefore, the engine control device according to the present invention is applied to control the engine mounted on the vertical take-off and landing aircraft, and in the event of an emergency where the other engine fails, the output of 130% of the maximum rated output is the maximum output. And As a result, the maximum output per engine can be 65% of the maximum rated output when both engines are normal and the output required by the aircraft is supplied by two engines. Driving can be performed at a close location, and fuel consumption can be improved.

  As a result, if the output required by the fuselage is the same, the engine can be downsized, making it possible to make the vertical take-off and landing aircraft more compact and lighter, thereby further improving fuel efficiency. be able to.

  As described above, according to the present invention, it is possible to reduce the weight and improve the fuel consumption.

  The best mode for carrying out the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the best mode are not intended to limit the scope of the present invention only to those unless otherwise specified. Absent.

  FIG. 1 is a view showing an appearance of a vertical take-off and landing aircraft 1 according to the best mode of the present invention. As shown in this figure, the vertical take-off and landing aircraft 1 is provided with two thrust generators (thrust generating means) 2 before and after the fuselage, and a driving source 3 and one passenger seat 4 are provided between them. ing.

  FIG. 2 shows an outline of the configuration of the drive source 3, which includes two gas turbine engines (hereinafter sometimes simply referred to as “engines”) 10. The engine 10 includes a compressor 11, a combustor 12, and a turbine 13. Then, the air (intake air) drawn into the compressor 11 is compressed by the compressor 11, and mixed with the fuel supplied by a fuel injection device (not shown) and burned in the combustor 12, and the combustion gas is compressed by the compressor 11. And the turbine 13 directly connected to the rotary shaft 14 is driven and then discharged to the outside of the engine.

  Further, the extraction flow path 15 is connected to the compressor 11, and a part of the compressed air generated in the compressor 11 is discharged to the extraction flow path 15. Each extraction flow path 15 of each engine 10 is connected to a collective air flow path 17, and compressed air extracted from each compressor 11 is collected in the collective air flow path 17. A check valve 16 is provided in the middle of each extraction flow path 15 to allow the compressed air to flow from the compressor 11 toward the collective air flow path 17, but from the collective air flow path 17 to the compressor. 11 is not allowed to circulate. This prevents compressed air from the two engines from interfering with each other.

The collective air flow path 17 is connected to four thrust air flow paths 18. Each of the four thrust air flow paths 18 is driven based on a command from an ECU, which will be described later, and an air flow rate control valve (flow control) that can change the flow area in the thrust air flow path 18. Means) 19 is provided. Each of the four thrust air passages 18 is connected to the thrust generator 2.

  FIG. 3 shows an outline of the configuration of the thrust generator 2, and the thrust generator 2 mainly includes a turbine 21, a speed reducer 22, and a fan 23. The turbine 21 is rotationally driven by the energy generated when the compressed air flowing in from the thrust air flow path 18 expands, and is decelerated by the speed reducer 22 to rotate the fan 23. Then, the fan 23 rotates at a high speed and generates an air flow downward in the fuselage, thereby generating thrust almost vertically upward with respect to the fuselage. The vertical take-off and landing aircraft 1 can take off / land in the vertical direction by the thrust generated by the thrust generator 2.

  Compressed air necessary for the thrust of the fuselage is taken out once after passing through the check valve 16 in order to prevent interference between the two engines. The compressed air from each engine is collected in the collecting air flow path 17 and then guided to the air flow control valve 19. The air flow control valve 19 is for controlling the thrust of the fuselage, and the compressed air adjusted by the air flow control valve 19 is guided to the thrust generator 2 so that the pilot intends to generate the thrust. It has become.

  Moreover, after taking off, the thrust for advancing to the front, back, left and right can be obtained by inclining the airframe and utilizing the component force of the thrust generated by the thrust generator 2. The tilt angle of the airframe at this time is controlled by the air flow control valve 19 by controlling the amount of compressed air guided to the thrust generator 2 in front of and behind the airframe in conjunction with the control stick, and the rotational speed of the fan 23 is controlled. Can be adjusted.

  An accumulator 20 serving as a pressure fluctuation suppressing means is provided to suppress pressure fluctuations in the extraction flow path 15 and the collective air flow path 17 by operating the air flow rate control valve 19.

  Since the thrust generator 2 generates thrust by using the compressed air discharged from the engine 10 as described above, the engine 10 and the thrust generator 2 are connected only by an air flow path such as an extraction flow path. can do. Therefore, the arrangement of the thrust generator 2 can be freely set as compared with the case where the engine and the thrust generator 2 are mechanically connected. In addition, since the number, size, etc. of the thrust generators 2 can be freely set according to the size of the flying object, this also increases the degree of freedom of arrangement of the thrust generators 2. . And thereby, it can be set as the vertical take-off and landing aircraft which implement | achieved compactness and weight reduction as shown in FIG.

  The reason why the two engines 10 are used is that safety is taken into consideration. That is, even if one of the two engines 10 breaks down, the remaining one engine 10 can meet the required output of the aircraft to improve safety.

  The vertical take-off and landing aircraft 1 configured as described above includes a first electronic control unit (ECU) 30 as an engine control device that is attached to each engine 10 and controls the engine 10, and thrust. A second electronic control unit (ECU) 31 that controls the air flow control valve 19 for adjustment is installed. These ECUs 30 and 31 are arithmetic logic operation circuits including a CPU, a ROM, a RAM, a backup RAM, and the like.

  Various sensors such as a rotation angle sensor 32 that detects the rotation speed of the rotating shaft 14 of the engine 10 are connected to the ECU 30 via electric wiring, and output signals of the various sensors described above are input to the ECU 30. Yes. The rotation angle sensor 32 is, for example, disposed near the rotation shaft 14 and generates a pulse signal at every predetermined rotation angle (for example, every 60 degrees), and the ECU 30 is based on the pulse signal input at regular intervals. Then, the rotational speed (engine speed) N of the rotary shaft 14 is calculated.

  Further, the ECU 30 calculates the amount of fuel to be injected into the combustor 12 based on a preset schedule based on an input signal from the rotation angle sensor 32 and the like, and a command value for the calculated fuel amount. Is output to a fuel supply actuator (not shown), and the fuel injection device is controlled based on the command value.

  In the vertical take-off and landing aircraft 1 according to the present embodiment, when both the two engines 10 operate normally, the required output of the aircraft is met with equal output from both engines. Then, even if the engine output changes, the ECU 30 basically operates the fuel injection device so as to keep the engine speed constant at the rated speed (N = 100%), and supplies appropriate fuel to the engine. It has become. That is, when the engine speed is lower than the rated speed, the ECU 30 increases the fuel injection amount. Conversely, when the engine speed is higher than the rated speed, the ECU 30 decreases the fuel injection amount and reduces the engine speed. It operates to achieve the rated speed.

  FIG. 4 shows general characteristics of the compressor. As shown in the figure, the characteristics of the compressor can be expressed as characteristics indicated by a solid line for each engine speed N. This is because, when the compressor rotation speed N is constant, the pressure P3 at the outlet of the compressor decreases when the air flow rate Ga extracted from the compressor is large, and the pressure P3 at the outlet of the compressor increases when the air flow rate Ga extracted from the compressor decreases. It shows that it has such characteristics.

  In the vertical take-off and landing aircraft 1 according to the present embodiment, when the two engines 10 operate normally, the rated rotational speed (N = 100) shown in FIG. %) Is controlled to output along the curve.

  In FIG. 4, θ is the atmospheric temperature / standard atmospheric temperature, and δ is a value indicating atmospheric pressure (P0) / standard atmospheric pressure. Further, FIG. 4 shows a surge region, which is a region indicating where surging occurs for each air flow rate Ga taken out from the compressor, and the allowable temperature limit of the turbine inlet temperature (T4). For example, N = 80% indicates that the rotation speed is 80% of the rated rotation speed (N = 100%).

  Each ECU 30 has an engine abnormality detector (not shown) that detects whether the engine 10 has failed and cannot generate a desired output based on output signals from various sensors. When the engine abnormality detector detects that the engine 10 has failed and cannot generate a desired output, an emergency (hereinafter referred to as “EMG”) signal that is an abnormality signal is output to the other ECU 30. It has become. On the other hand, when it is detected that the engine 10 has not failed, the EMG signal is not output to the other ECU 30.

  Each ECU 30 has an abnormal signal input device (not shown) for inputting the EMG signal from the ECU 30 provided in the other engine 10 output as described above, and the abnormal signal input device. When the EMG signal is input, the ECU 30 switches the EMG flag from OFF to ON. That is, when the EMG flag is OFF, the other engine 10 is normal, and when the EMG flag is ON, the other engine 10 is not normal.

  Note that whether or not the engine 10 has failed depends on whether the engine speed N does not exceed the predetermined speed even though a predetermined amount of fuel is supplied to the combustor 12, and the rotational speed of the rotary shaft 14. It can be determined by detecting that the outlet pressure of the compressor 11 is lower than the predetermined pressure even though the predetermined rotational speed is reached.

  In the vertical take-off and landing aircraft 1 according to the present embodiment, as described above, when the two engines 10 are mounted and both the engines are operating normally, the required output is obtained with equal output from both engines. To respond.

  On the other hand, when one of the two engines 10 breaks down and a desired engine output cannot be generated, it is necessary to meet the required output of the aircraft with only the normal engine 10. In the vertical take-off and landing aircraft 1 according to the present embodiment, an emergency output operation that is not used in normal operation is enabled as such an emergency operation method. That is, when one of the engines fails, the rotational speed of the normal engine 10 is increased by about 5%, and the inlet temperature (T4) of the turbine 13 is increased by about 5% with respect to the allowable temperature limit (T4 = 100%). Try to raise. That is, the engine speed is kept constant at N = 105%, and the inlet temperature (T4) of the turbine 13 is made 105% at the maximum. By doing so, the output per engine is increased by about 30% at maximum with respect to the maximum rated output that can be used continuously without any use restriction.

  In a relatively large vertical take-off and landing aircraft such as a helicopter, it is impossible to land anywhere in the event of an emergency where one of the two engines has failed. It is required to continue the flight to some extent. For this reason, the engine output is currently designed with some margin. In contrast, a small vertical take-off and landing aircraft (up to 4 passengers) such as the vertical take-off and landing aircraft 1 according to the present embodiment can land even in a relatively small space, and one engine seems to have failed. Even in an emergency, it is possible to land early, so that it is not necessary to allow a sufficient margin in engine output.

  In view of such matters, the engine 10 according to the present embodiment is applied only to a small vertical take-off and landing aircraft as shown in FIG. 1, and the maximum rated output that can be used continuously without use limitation is 100%. In such a case, an emergency output in which one of the two engines has failed can be output to 130% for a limited time (about 2.5 minutes).

  In this way, in the event of an emergency where one unit fails, by using an output of 130% (1.3 times) of the maximum rated output, it is not necessary to mount an engine with a relatively large surplus output. The engine can be reduced in size and weight. As a result, the airframe can be reduced in size and weight, and fuel efficiency can be improved for the following reasons.

  FIG. 5 shows the rate of change in fuel consumption with respect to engine output (the larger the number, the worse the fuel consumption). Originally, the engine output of a relatively large aircraft such as a helicopter is selected so that even one engine can continue to fly to some extent. Therefore, the output (maximum rated output) point of the engine 100% is the maximum output required for the engine when the aircraft flies with one engine.

  When the output required by the fuselage is to be supplied by two engines, the maximum output per engine is 50% of the maximum rated output, and the fuel efficiency in this case is significantly higher than at 100% output. It will get worse.

In the vertical take-off and landing aircraft 1 according to the present embodiment, in the event of an emergency where one unit fails, the emergency output of the engine is used so that the output necessary for the aircraft to fly is output at a maximum output point of 130%. Therefore, when both units are normal and the required output of the aircraft is supplied by the two units, the maximum output per engine may be 65% of the maximum rated output. As a result, even when both units are normal and fly with two equal outputs, the engine can be operated near the maximum rated output point. As a result, it is possible to reduce the influence of the deterioration of the fuel consumption of the vehicle and to greatly improve the fuel consumption of the entire aircraft.

  In the vertical take-off and landing aircraft 1 configured as described above, each ECU 30 controls the amount of fuel supplied to the combustor 12 as follows.

  As an outline, when the EMG flag is OFF, an appropriate fuel is supplied to the engine via the fuel injection device so that the engine speed is constant at the rated speed (N = 100%). That is, in such a case, the maximum rated output is set as the upper limit (with the turbine inlet temperature T4 as the upper limit of the allowable temperature limit (T4 = 100%)), and the target engine speed is set as the rated speed according to the required output from the aircraft. The engine output is changed while keeping the number. However, in practice, 50% of the maximum rated output is the upper limit (the turbine inlet temperature T4 varies depending on the engine specifications, and the upper limit is 50 to 80% of the allowable temperature limit).

  On the other hand, when the EMG flag is ON, the engine speed is set to 130% of the maximum rated output as the upper limit (the turbine inlet temperature T4 is set to 105% of the allowable temperature limit as the upper limit) according to the required output from the aircraft. The amount of fuel supplied to the engine is controlled so that the number is constant at 105%.

  Specifically, it is executed according to the fuel injection amount control routine shown in the flowchart of FIG. This control routine is to be executed by each ECU 30 as an interrupt process every time a fixed time elapses.

  First, in step (hereinafter, sometimes simply referred to as “S”) 101, the EMG flag is read. Thereafter, the process proceeds to S102, and the engine operating conditions such as the engine speed N, the atmospheric temperature T0, the atmospheric pressure P0, the compressor outlet temperature T3, the compressor outlet pressure P3, and the turbine inlet temperature T4 are grasped based on the output signals of various sensors. It detects the engine state quantity for

  Thereafter, the process proceeds to S103, and it is determined whether or not the EMG flag is ON. If a positive determination is made, the process proceeds to S104, where the maximum engine speed (Nmax) is set to 105% and the maximum turbine inlet temperature (T4max) is set to 105%. On the other hand, if a negative determination is made, the process proceeds to S105, where the maximum engine speed (Nmax) is set to 100% and the maximum turbine inlet temperature (T4max) is set to 100%.

  Thereafter, the process proceeds to S106, where the deviation between the actual engine speed (actual speed) and the target speed is calculated, and in S107, the fuel injection amount Gf is calculated based on the speed difference calculated in S106. That is, when the actual rotation speed N is the same as the target rotation speed, the previous fuel injection amount value is calculated as the current fuel injection amount Gf. On the other hand, when the actual rotational speed is different from the target rotational speed and the actual rotational speed is lower than the target rotational speed, the fuel injection amount is corrected to be increased from the previous time, and conversely, the actual rotational speed is higher than the target rotational speed. In this case, the fuel injection amount is corrected so as to decrease from the previous time. The amount of correction is calculated by substituting the rotational speed deviation into a predetermined map.

  Thereafter, the process proceeds to S108, and the fuel injection amount Gf calculated in S107 is set as the amount to be injected next time.

FIG. 7 shows the operation of the engine 10 in which the fuel injection amount is controlled in this way in time series. The horizontal axis of this figure has shown elapsed time. Until time t1, two engines 10 are operating normally, and after time t1, one of the two engines 10 is broken.

  And, in this way, by setting the maximum engine output in an emergency where one unit has failed to an output of 130% (1.3 times) the maximum rated output, an engine with a large surplus output can be installed. As a result, the engine can be reduced in size and weight. As a result, the airframe can be reduced in size and weight, and fuel consumption can be improved.

  In addition, the maximum use output when both units are operating normally can be 65% of the maximum rated output, and the engine can be operated near the maximum rated output point. Therefore, it is possible to reduce the influence of the deterioration of the fuel consumption in the low load state, which is a concern in the gas turbine engine, so that the fuel consumption can be greatly improved.

It is a figure which shows schematic structure of the vertical take-off and landing aircraft which concerns on an Example. It is a figure which shows schematic structures, such as a gas turbine engine. It is a figure which shows schematic structure of a thrust generator. It is a figure which shows the action | operation of the gas turbine engine which concerns on an Example on a compressor map. It is a figure which shows the relationship between the output of a gas turbine engine, and a fuel change rate. It is a flowchart which shows the fuel injection amount control routine which concerns on an Example. It is a figure which shows the action | operation of the vertical take-off and landing aircraft which concerns on an Example in time series.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vertical take-off and landing machine 2 Thrust generator 3 Drive source 4 Passenger seat 10 Gas turbine engine 11 Compressor 12 Combustor 13 Turbine 14 Rotating shaft 15 Extraction flow path 16 Check valve 17 Collecting air flow path 18 Thrust air flow path 19 Air flow rate Control valve 20 Accumulator 30 First ECU
31 2ECU
32 Rotation angle sensor

Claims (3)

Two gas turbine engines;
Two extraction passages through which compressed air discharged from each gas turbine engine flows;
Two check valves provided in each extraction passage;
An aggregate air flow path for allowing the compressed air that has flowed through the two extraction flow paths to gather and flow downstream of the check valve;
Thrust generating means for generating thrust using compressed air that has circulated through the collective air flow path;
Flow rate control means for controlling the amount of compressed air used for thrust generation by the thrust generation means;
Two engine control means for controlling each gas turbine engine;
Thrust control means for controlling the flow rate control means to control the thrust generated by the thrust generation means;
A vertical take-off and landing aircraft characterized by comprising:   The vertical take-off and landing aircraft according to claim 1, further comprising pressure fluctuation suppressing means for suppressing pressure fluctuation of compressed air that has flowed into the collective air flow path from the two extraction flow paths. Two gas turbine engines;
Two extraction passages through which compressed air discharged from each gas turbine engine flows;
Two check valves provided in each extraction passage;
An aggregate air flow path for allowing the compressed air that has flowed through the two extraction flow paths to gather and flow downstream of the check valve;
Thrust generating means for generating thrust using compressed air that has circulated through the collective air flow path;
Flow rate control means for controlling the amount of compressed air used for thrust generation by the thrust generation means;
Thrust control means for controlling the flow rate control means to control the thrust generated by the thrust generation means;
An engine control device for controlling one of two engines of a vertical take-off and landing aircraft comprising:
An engine control apparatus for a vertical take-off and landing aircraft, characterized in that if the other engine fails, the output is 130% of the maximum rated output.

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