A method for controlling the longitudinal center of gravity of a helicopter

Abstract

This invention belongs to the field of helicopter design technology, and particularly relates to a method for controlling the longitudinal center of gravity of a helicopter. The method includes: acquiring characteristic data of the helicopter; determining the combined fuel weight G under the pre-limit loading state. 油前 Center of gravity C 油前 The total fuel weight G under the ultimate loading condition was determined. 油后 Center of gravity C 油后 Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Minimum value; determines the fuel consumption ΔG of the receiving tank at the start of transfer. 受油 Maximum value; determine the amount of oil transferred ΔG 输油 Minimum value; determine the amount of oil transferred ΔG 输油 Maximum value; ΔG 受油 ΔG 输油 Provides fuel system design to enable automatic transfer functionality.

Description

Technical Field

[0001] This invention belongs to the field of helicopter design technology, and in particular relates to a method for controlling the longitudinal center of gravity of a helicopter. Background Technology

[0002] The center of gravity of a helicopter affects flight safety, flight quality, airframe lifespan, development cycle, and cost; therefore, its use must be limited to a certain range. Conventional methods for controlling the helicopter's center of gravity include adjusting the empty center of gravity and limiting payload, mainly through equipment layout adjustments, local weight adjustments, and restrictions on payload position and order. However, these methods have drawbacks such as high workload and difficulty, increased development cycle and cost, and numerous usage restrictions. Summary of the Invention

[0003] The technical problem solved by this invention is that by using an automatic control system with variable load during flight, the center of gravity of a helicopter can be effectively limited within its envelope.

[0004] The technical solution of this invention:

[0005] A method for controlling the longitudinal center of gravity of a helicopter, the method comprising:

[0006] Step 1: Obtain helicopter characteristic data;

[0007] Step 2: Determine the total fuel weight G under the pre-limit loading condition. 油前 Center of gravity C 油前 ;

[0008] Step 3: Determine the total fuel weight G under the ultimate loading condition. 油后 Center of gravity C 油后 ;

[0009] Step 4: Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Minimum value;

[0010] Step 5: Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Maximum value;

[0011] Step 6: Determine the transfer volume ΔG 输油 Minimum value;

[0012] Step 7: Determine the transfer volume ΔG 输油 Maximum value;

[0013] Step 8: Adjust ΔG 受油 ΔG 输油 Provides fuel system design to enable automatic transfer functionality.

[0014] Furthermore, in the first step, the characteristic data includes at least the weight center of gravity envelope limit C. 前 and posterior limit C后 Empty weight G 空 and center of gravity C 空 Unit weight G 机组 and center of gravity C 机组 Commercial load weight G 商 and center of gravity C 商 The weight G of fuel in the fuel tank 输油 Center of gravity C 输油 And fuel consumption rate V 输油耗 The weight G of the fuel in the fuel tank 受油 Center of gravity C 受油 And fuel consumption rate V 受油耗 Fuel transfer rate V 转 .

[0015] Furthermore, in the second step,

[0016] G 油前 *C 油前 ≥(G 空 +G 机组 +G 商 +G 油前 )*C 前 -(G 空 *C 空 +G 机组 *C 机组 +G 商 *C 商 ).

[0017] Furthermore, in the third step,

[0018] G 油后 *C 油后 ≤(G 空 +G 机组 +G 商 +G 油后 )*C 后 -(G 空 *C 空 +G 机组 *C 机组 +G 商 *C 商 ).

[0019] Furthermore, in the fourth step,

[0020] ΔG 受油 ≥(G 输油 *C 输油 +G 受油 *C 受油 -G 油后 *C 油后 )*V 受油耗 / (V 输油耗 *C 输油 +V受油耗

[0021] *C 受油 ).

[0022] Furthermore, in the fifth step,

[0023] ΔG 受油 ≤(G 输油 *C 输油 +G 受油 *C 受油 -G 油前 *C 油前 )*V 受油耗 / (V 输油耗 *C 输油 +V 受油耗

[0024] *C 受油 ).

[0025] Furthermore, in step six,

[0026] ΔG 输油 ≥(G 输油 *C 输油 +G 受油 *C 受油 -G 油后 *C 油后 -ΔG 受油 *C 受油 -ΔG 受油 *C 输油 *V 输

[0027] 油耗 / V 受油耗 ) / (C 输油 -C 受油 +V 输油耗 *C 输油 / V 转 +V 受油耗 *C 受油 / V 转 ).

[0028] ΔG 输油 ≤(G 输油 *C 输油 +G 受油 *C 受油 -G 油前 *C 油前 -ΔG 受油 *C 受油 -ΔG 受油 *C 输油 *V 输

[0029] 油耗 / V受油耗 ) / (C 输油 -C 受油 +V 输油耗 *C 输油 / V 转 +V 受油耗 *C 受油 / V 转 ).

[0030] Furthermore, in step eight,

[0031] The fuel transfer start conditions determined in steps four and five, and the fuel transfer amount determined in steps six and seven, are used as inputs to the fuel system design to achieve automatic transfer function.

[0032] For helicopters with fuel tanks distributed in front and behind, the transfer start conditions and transfer amount are determined based on the weight center envelope and loading data. Through automatic fuel transfer, the helicopter's center of gravity is controlled during flight, thereby ensuring that the helicopter's center of gravity does not exceed the limit throughout the entire flight profile. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating a method for controlling the longitudinal center of gravity of a helicopter.

[0034] Figure 2 This is a schematic diagram showing the relationship between the longitudinal center of gravity and the weight. Detailed Implementation

[0035] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0036] In addition to commercial payload, variable load during flight also includes fuel. For helicopters with fuel tanks distributed front and rear, the transfer initiation conditions and transfer fuel quantity are determined based on the weight center of gravity envelope and load data. Through automatic fuel transfer, the helicopter's center of gravity is controlled during flight, thereby ensuring that the helicopter's center of gravity does not exceed limits throughout the entire flight profile. Figure 1 As shown, the specific steps are as follows:

[0037] Step 1: Obtain the helicopter's characteristic data, including at least the weight, center of gravity envelope front limit of 6.2C. 前 and hind limit 6.6C 后 Empty weight 2000g 空 and center of gravity 6.6C 空 Unit weight 200G 机组 and center of gravity 2C 机组 The payload is 1000g. 商 and center of gravity 7C 商 The fuel in the fuel tank weighs 400g. 输油 Center of gravity 6C 输油 And fuel consumption rate 200V输油耗 The weight of the fuel in the fuel tank is 400g. 受油 Center of gravity 7C 受油 And fuel consumption rate 200V 受油耗 Fuel transfer rate 400V 转 wait;

[0038] Step 2: Determine the total fuel weight G under the pre-limit loading condition. 油前 Center of gravity C 油前 ;

[0039] G 油前 *C 油前 ≥(G 空 +G 机组 +G 商 +G 油前 )*C 前 -(G 空 *C 空 +G 机组 *C 机组 +G 商 *C 商 )

[0040] (2000+200+1000+400)*6.2-(2000*6.6+200*2+1000*7)=1720

[0041] Step 3: Determine the total fuel weight G under the ultimate loading condition. 油后 Center of gravity C 油后 ;

[0042] G 油后 *C 油后 ≤(G 空 +G 机组 +G 商 +G 油后 )*C 后 -(G 空 *C 空 +G 机组 *C 机组 +G 商 *C 商 )

[0043] (2000+200+1000+400)*6.6-(2000*6.6+200*2+1000*7)=3160

[0044] Step 4: Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Minimum value;

[0045] ΔG 受油 ≥(G 输油 *C 输油 +G受油 *C 受油 -G 油后 *C 油后 )*V 受油耗 / (V 输油耗 *C 输油 +V 受油耗

[0046] *C 受油 )

[0047] (400*6+400*7-400*7)*200 / (200*6+200*7)=185

[0048] Step 5: Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Maximum value;

[0049] ΔG 受油 ≤(G 输油 *C 输油 +G 受油 *C 受油 -G 油前 *C 油前 )*V 受油耗 / (V 输油耗 *C 输油 +V 受油耗

[0050] *C 受油 )

[0051] (400*6+400*7-400*6)*200 / (200*6+200*7)=215

[0052] Step 6: Determine the transfer volume ΔG 输油 Minimum value;

[0053] ΔG 输油 ≥(G 输油 *C 输油 +G 受油 *C 受油 -G 油后 *C 油后 -ΔG 受油 *C 受油 -ΔG 受油 *C 输油 *V 输

[0054] 油耗 / V 受油耗 ) / (C 输油 -C 受油 +V 输油耗 *C 输油 / V 转 +V 受油耗*C 受油 / V 转 )

[0055] (400*6+400*7-400*7-200*7-200*6*200 / 200) / (6-7+200*6 / 400+200*7 / 400)=-36

[0056] Step 7: Determine the transfer volume ΔG 输油 Maximum value;

[0057] ΔG 输油 ≤(G 输油 *C 输油 +G 受油 *C 受油 -G 油前 *C 油前 -ΔG 受油 *C 受油 -ΔG 受油 *C 输油 *V 输

[0058] 油耗 / V 受油耗 ) / (C 输油 -C 受油 +V 输油耗 *C 输油 / V 转 +V 受油耗 *C 受油 / V 转 )

[0059] (400*6+400*7-400*6-200*7-200*6*200 / 200) / (6-7+200*6 / 400+200*7 / 400)=36

[0060] Step 8: Adjust ΔG 受油 ΔG 输油 Provides fuel system design to enable automatic transfer functionality.

[0061] The fuel transfer start conditions determined in steps four and five, and the fuel transfer amounts determined in steps six and seven, are used as inputs to the fuel system design to achieve automatic transfer functionality.

[0062] like Figure 2 The diagram shows the relationship between the longitudinal center of gravity and the weight.

[0063] This invention provides a design method for controlling the center of gravity of a helicopter during flight. This design method is simple and quick, and can be rapidly adjusted and updated according to usage requirements, effectively reducing the pressure on helicopter center of gravity control. It has been successfully applied to a certain helicopter and has significant engineering application value.

Claims

1. A method for controlling the longitudinal center of gravity of a helicopter, characterized in that, The method includes: Step 1: Obtain the helicopter's characteristic data; in Step 1, the characteristic data shall include at least the leading limit C of the weight center of gravity envelope. 前 and posterior limit C 后 Empty weight G 空 and center of gravity C 空 Unit weight G 机组 and center of gravity C 机组 Commercial load weight G 商 and center of gravity C 商 The weight of fuel in the fuel tank G 输油 Center of gravity C 输油 And fuel consumption rate V 输油耗 The weight G of the fuel in the fuel tank 受油 Center of gravity C 受油 And fuel consumption rate V 受油耗 Fuel transfer rate V 转 ; Step 2: Determine the total fuel weight G under the pre-limit loading condition. 油前 Center of gravity C 油前 In the second step, G 油前 *C 油前 ≥(G 空 +G 机组 +G 商 +G 油前 )*C 前 -(G 空 *C 空 +G 机组 *C 机组 +G 商 *C 商 ); Step 3: Determine the total fuel weight G under the ultimate loading condition. 油后 Center of gravity C 油后 In the third step, G 油后 *C 油后 ≤(G 空 +G 机组 +G 商 +G 油后 )*C 后 -(G 空 *C 空 +G 机组 *C 机组 +G 商 *C 商 ); Step 4: Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Minimum value; in the fourth step, ΔG 受油 ≥(G 输油 *C 输油 +G 受油 *C 受油 -G 油后 *C 油后 )*V 受油耗 / (V 输油耗 *C 输油 +V 受油耗 *C 受油 ; Step 5: Determine the fuel consumption ΔG of the receiving tank at the start of the transfer. 受油 Maximum value; in step five, ΔG 受油 ≤(G 输油 *C 输油 +G 受油 *C 受油 -G 油前 *C 油前 )*V 受油耗 / (V 输油耗 *C 输油 +V 受油耗 *C 受油 ); Step 6: Determine the transfer volume ΔG 输油 Minimum value; in step six, ΔG 输油 ≥(G 输油 *C 输油 +G 受油 *C 受油 -G 油后 *C 油后 -ΔG 受油 *C 受油 -ΔG 受油 *C 输油 *V 输油耗 / V 受油耗 ) / (C 输油 -C 受油 +V 输油耗 *C 输油 / V 转 +V 受油耗 *C 受油 / V 转 ); ΔG 输油 ≤(G 输油 *C 输油 +G 受油 *C 受油 -G 油前 *C 油前 -ΔG 受油 *C 受油 -ΔG 受油 *C 输油 *V 输油耗 / V 受油耗 ) / (C 输油 -C 受油 +V 输油耗 *C 输油 / V 转 +V 受油耗 *C 受油 / V 转 ); Step 7: Determine the transfer volume ΔG 输油 Maximum value; Step 8: Adjust ΔG 受油 ΔG 输油 Provide fuel system design to achieve automatic transfer function; in step eight, The fuel transfer start conditions determined in steps four and five, and the fuel transfer amount determined in steps six and seven, are used as inputs to the fuel system design to achieve automatic transfer function.

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