Hydrogen fuel aero-engine architecture analysis method based on analysis

Abstract

The invention discloses a hydrogen fuel aero-engine architecture analysis method based on analysis, which comprises the following steps: establishing a component thermodynamic model of an aero-engine, taking hydrogen fuel as a power source, and calculating through the model to obtain total temperature and total pressure parameters and thrust and oil consumption rate parameters of each component section of the hydrogen fuel aero-engine; on the basis of an energy balance equation of a stable flow system, flow models of all parts of the hydrogen fuel aero-engine are constructed, and flow calculation of the parts of the hydrogen fuel aero-engine is achieved through coupling of the flow models of the parts and a thermodynamic model; establishing three evaluation indexes of loss rate, efficiency and loss coefficient, identifying a hydrogen fuel aero-engine component flow calculation result based on the evaluation indexes, and determining a weak link of system energy utilization; based on the analysis result, topological structure change and comprehensive thermal management research are carried out on the hydrogen fuel aero-engine system by adding heat exchanger components, and the overall performance of the hydrogen fuel aero-engine system is improved.

Description

Technical Field

[0001] The present invention relates to aeroengine thermal management technology, more specifically, a Analytical methods for hydrogen fueled aero engine architecture analysis. Background Art

[0002] In the era of global climate change, carbon emissions have become the biggest non-traditional security issue facing human development. As the world's energy structure accelerates its evolution towards low-carbon and carbon-free, the aviation industry faces challenges brought about by profound changes in the global energy system. The use of hydrogen fuel is the mainstream development trend in the aviation field to cope with climate change and achieve carbon emission reduction. Hydrogen fuel has great potential to become the main energy option for the aviation industry to achieve carbon reduction goals in the future. Aviation engine hydrogen combustion technology has shown significant potential advantages in the aviation field, and its technical feasibility has been proven. The manufacturing, storage, transportation, and use of hydrogen fuel also have an existing industrial foundation.

[0003] Aircraft using hydrogen-fueled aviation engines require 35% of the amount of fuel of traditional aircraft to complete the same flight mission, and can significantly reduce the maximum take-off weight of the aircraft. At the same time, hydrogen fuel also has the characteristics of clean combustion. Compared with traditional aircraft, the impact of using hydrogen fuel on the climate can be reduced by 50% to 75%. The use of hydrogen fuel in the aviation industry can not only achieve zero carbon dioxide emissions, but also effectively reduce the emissions of pollutants such as carbon monoxide and sulfides. In addition, hydrogen has a wide combustion range and low ignition energy, so the flight operating envelope of hydrogen-fueled aviation engines is wider and the air starting envelope is higher, and it can be started in plateau environments with thin air. In addition to the above advantages, hydrogen fuel also has good low-temperature characteristics and high specific heat capacity characteristics. Relying on its superior cooling and heat exchange capabilities, it can effectively cool the hot end components of the engine.

[0004] However, for aircraft engines using hydrogen fuel, the huge changes in the fuel properties will have a certain impact on their cycle characteristics, which will in turn cause changes in the degree and pattern of energy loss in each component. Summary of the invention

[0005] The purpose of the present invention is to provide a The hydrogen fuel aircraft engine architecture analysis method analyzed can accurately identify the weak links in the energy utilization of hydrogen fuel aircraft engine systems, analyze and improve them, and make full use of the system The energy contained in the links with large losses can be maximized to maximize its surplus value, improve the performance of hydrogen fuel aircraft engines, and achieve thermal management of hydrogen fuel aircraft engine systems.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A kind of The hydrogen fuel aircraft engine architecture analysis method includes the following steps:

[0008] Step 1, establish a thermodynamic model of aircraft engine components, use hydrogen fuel as the power source, and calculate the total temperature T, total pressure parameter P, mass flow W and thrust F, and fuel consumption rate SFC parameters of each cross section of the hydrogen fuel aircraft engine components through the model;

[0009] Step 2, based on Computational model and energy balance equation of stable flow system, construction of various components of hydrogen fuel aircraft engine Flow model, through components Coupling flow model and thermodynamic model to realize hydrogen fuel aviation engine components Stream computing;

[0010] Step 3, Set up Loss rate, efficiency, Three loss factors Evaluation indicators, based on Evaluation indicators for hydrogen fuel aircraft engine components Identify the weak links in system energy utilization based on the flow calculation results;

[0011] Step 4, based on The analysis results show that by adding heat exchanger components, the topological structure change and comprehensive thermal management research of the hydrogen fuel aircraft engine system can be carried out to improve the performance of the hydrogen fuel aircraft engine system.

[0012] Furthermore, in step 1, the aircraft engine component-level modeling method is used to calculate the cross-sectional total temperature T, cross-sectional total pressure P, mass flow W, fuel consumption rate SFC, and thrust F parameters. The specific process includes the following steps:

[0013] Step 2.1: According to the physical characteristics of each component of the aircraft engine, the thermodynamic models of the inlet, low-pressure compressor, high-pressure compressor, combustion chamber, high-pressure turbine, low-pressure turbine, inner nozzle and outer nozzle are established in sequence. When the total temperature T of the working fluid at the inlet section of the component is determined in , total pressure P in , and mass flow rate W in When the total temperature T of the working fluid at its outlet section is obtained through the thermodynamic model of the component out , total pressure P out , and mass flow rate W out ;

[0014] Step 2.2: After connecting the component models in series, the airflow parameters of each component cross section are calculated according to the aero-engine gas flow path. This calculation process complies with the constraints of the steady-state joint working equation of the aero-engine.

[0015] Step 2.3: Use the least squares method to solve the common working equation that contains the entire aircraft engine steady-state model, and bring the mass flow rate W, speed N, and pressure ratio π design parameters that satisfy the common working equation into the aircraft engine steady-state model to obtain the component cross-sectional parameters and thrust F, fuel consumption rate SFC parameters that meet the current operating conditions of the aircraft engine.

[0016] In step 2, based on Computational model and energy balance model of stable flow system, construction of various components of hydrogen fuel aircraft engine Flow model, through components Coupling flow model and thermodynamic model to realize hydrogen fuel aviation engine components Stream computing.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) The present invention combines the aircraft engine component model with The energy capacity is used as the evaluation index to measure the availability of the energy. Flow analysis can accurately identify the root causes of energy dissipation and inefficient energy utilization in the system.

[0019] (2) A framework analysis method is proposed for hydrogen fuel aircraft engine systems, mainly based on the components of hydrogen fuel aircraft engines According to the analysis results, a thermal management architecture for hydrogen fuel aircraft engines was established by adding components such as heat exchangers to improve the system performance of hydrogen fuel aircraft engines. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a topological structure diagram of the hydrogen fuel aviation engine in the present invention;

[0021] Figure 2 It is a flow chart of the performance calculation of the aircraft engine in the present invention;

[0022] Figure 3 It is a schematic diagram of the gas flow path of the aero-engine in the present invention;

[0023] Figure 4 The hydrogen fuel aircraft engine system in the specific embodiment of the present invention Flow situation diagram;

[0024] Figure 5The components of the hydrogen fuel aircraft engine in the specific embodiment of the present invention are Loss rate diagram;

[0025] Figure 6 It is a schematic diagram of the topological architecture of an improved hydrogen fuel aircraft engine in a specific embodiment of the present invention;

[0026] Figure 7 1 is a performance comparison diagram of a hydrogen fuel aircraft engine before and after the improved topology architecture in a specific embodiment of the present invention, wherein (a) is a comparison of the fuel consumption rate between the original architecture and the improved architecture, (b) is a comparison of the thrust between the original architecture and the improved architecture, and (c) is a comparison of the thrust between the original architecture and the improved architecture. Calculate the comparison. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] A kind of The hydrogen fuel aircraft engine architecture analysis method includes the following steps:

[0029] Step 1, such as Figure 1 Shown is the topological architecture diagram of the hydrogen fuel aviation engine system.

[0030] According to the physical characteristics of each component of the aero-engine, an aero-engine performance calculation model is established. With the steady-state joint working equation as a constraint, the total temperature T, total pressure P, mass flow W, thrust F, and fuel consumption SFC parameters of each cross-section of the hydrogen fuel aero-engine component are obtained through iterative calculation. The calculation process is as follows: Figure 2 shown.

[0031] 1) The thermodynamic models of the inlet, low-pressure compressor, high-pressure compressor, combustion chamber, high-pressure turbine, low-pressure turbine, inner nozzle and outer nozzle are established in sequence. When the total temperature T of the working fluid at the inlet section is determined, in , total pressure P in , and mass flow rate W in When the thermodynamic model of the component is used, the total temperature T of the working fluid at its outlet section can be obtained. out , total pressure P out , and mass flow rate W out The gas flow path after the components are connected in series is as follows Figure 3 shown.

[0032] 2): After connecting the component models in series, the airflow parameters of each component cross section are calculated according to the aero-engine gas flow path. The calculation process must comply with the constraints of the steady-state joint working equation of the aero-engine.

[0033] 3): Use the least squares method to solve the common working equation containing the entire aircraft engine steady-state model, and obtain the high-pressure compressor pressure ratio π that satisfies the common working equation H 、Low pressure compressor pressure ratio π L , mass flow W, high pressure rotor speed N H , low pressure rotor speed N L And other design parameters.

[0034] 4): Bringing the obtained design parameters into the model can calculate the engine operating parameters that meet the current working conditions, thereby calculating the thrust F and fuel consumption rate SFC of the aircraft engine. The calculation expressions of thrust F and fuel consumption rate SFC are:

[0035] F=W(V-V0)+A(Ps-Ps0) (1)

[0036] In the formula, V0, P s0 is the aircraft flight speed and the external atmospheric static pressure; W is the nozzle outlet cross-sectional mass flow rate; V is the nozzle exhaust velocity; A, A 15 is the nozzle outlet cross-sectional area; P s Static pressure at nozzle exit section.

[0037]

[0038] Where, F is the total thrust of the aircraft engine; W f is the fuel mass flow rate.

[0039] Step 2, based on Computational model and energy balance equation of stable flow system, construction of various components of hydrogen fuel aircraft engine Flow model, through components Coupling flow model and thermodynamic model to realize hydrogen fuel aviation engine components Stream computing.

[0040] 1): Determine the baseline environmental model, including the baseline environmental temperature, baseline environmental pressure, and environmental gas molar component parameters.

[0041] 2): Build The value calculation model is based on the potential energy difference and kinetic energy difference of the aircraft engine. Since the change value of the potential energy difference and kinetic energy difference inside the aircraft engine is small, the total E mainly includes physical E PH and Chemistry E CH Two items.

[0042] Among them, physics E PH The calculation expression is:

[0043] E PH =W[h-h0-T0(s-s0)] (3)

[0044] Where W is the mass flow rate; h and s are the specific enthalpy and specific entropy of the system working fluid in a certain state; h0, s0 and T0 are the specific enthalpy, specific entropy and temperature of the reference environment.

[0045] Chemical E CH The calculation expression is:

[0046]

[0047] In the formula, the first term on the right represents the chemical reaction produced by the chemical reaction when the system reaches a free equilibrium state. ; The second term is the chemical diffusion caused by the diffusion of chemical substances due to concentration differences .

[0048] System Total E for Chemistry and physics The calculation expression is:

[0049] E=E PH +E CH (5)

[0050] 3): Based on the energy balance principle, the energy balance equation of the stable flow system is constructed, and its expression is:

[0051]

[0052] In the formula, E i For inflow system ; E e For outflow system ; W is the mass flow rate of the working fluid flowing through the system; h1, s1 and V1 are the enthalpy, entropy and relative velocity of the incoming working fluid; h2, s2 and V2 are the enthalpy, entropy and relative velocity of the outflowing working fluid, T0 is the reference ambient temperature, and T is the temperature of the working fluid at a certain moment.

[0053] 4): Based on the above The calculation model and the energy balance equation of the stable flow system are used to establish the internal components of the aircraft engine. Stream computing model, components The stream computing model is as follows:

[0054] Intake Stream computing model:

[0055] I Inlet =E inInlet -E outInlet (7)

[0056] In the formula, I Inlet For air intake components Loss; E inInlet With E outInlet is the sum of the inlet and outlet air flows value.

[0057] Compressor Stream computing model:

[0058] I Compressor =E inCompressor -E outCompressor +L C (8)

[0059] In the formula, I Conmpressor For compressor parts Loss; E inConmpressor With E outConmpressor The total air flow at the compressor inlet and outlet Value; L C is the power consumption of the compressor components.

[0060] Combustion Chamber Stream computing model:

[0061] I Combustor =∑E inCombustor -E outCombustor (9)

[0062] In the formula, I Combustor It's the combustion chamber Loss; ∑E inCombustor is the total amount of material entering the combustion chamber Value, including air and fuel; E outCombustor is the total amount of material at the combustion chamber outlet value, its main component is gas.

[0063] turbine Stream computing model:

[0064] I Turbine =E inTurbine -E outTurbine -L T (10)

[0065] In the formula, I Turbine For turbine components Loss; E inTurbine With E outTurbine is the total of the turbine component inlet and outlet airflow Value; L T It is the shaft work output by the turbine.

[0066] Nozzle Stream computing model:

[0067] I Nozzle =E inNozzle -E outNozzle (11)

[0068] In the formula, I Nozzle For nozzle parts Loss; E inNozzle With E outNozzle is the total flow rate at the nozzle inlet and outlet , for physics With kinetic energy sum.

[0069] Components to be built The flow model is coupled to the thermodynamic model of the aircraft engine components, and steps 1 and 2 are repeated to calculate the overall thermodynamics of the hydrogen fuel aircraft engine system. Flow conditions, such as Figure 4 shown.

[0070] Step 3, in the component Based on the flow model, we set up Efficiency k , Loss rate θ k , Loss coefficient ξ k Three Evaluation index, its calculation expression is as follows:

[0071] Efficiency k :

[0072]

[0073] In the formula, the subscript k represents a component of the system; γ k For component k Efficiency; E out,k is the output of component k Value; E in,k is the input of component k value.

[0074] Loss rate θ k :

[0075]

[0076] In the formula, θ k For component k Loss rate; I k is the total number of components k Loss; ∑I k For the system loss.

[0077] Loss coefficient ξ k :

[0078]

[0079] In the formula, ξ k For component k Loss rate; E in is the total number of components k loss.

[0080] based on Evaluation indicators for hydrogen fuel aircraft engine components The calculation results of the flow are used to identify the weak links in the system energy utilization and calculate the The loss rate distribution is as follows Figure 5 shown.

[0081] Step 4: On the premise of meeting the thrust requirements, thermal management analysis and architecture changes of the hydrogen fuel aircraft engine system are established by adding heat exchanger components.

[0082] 1): Through the identification results of the energy weak links of the hydrogen fuel aircraft engine system, Conduct thermal management research on links with greater losses.

[0083] 2): Analysis The link with the largest loss is mainly determined through evaluation. Consider whether to recover waste heat based on the irreversibility of the damage.

[0084] 3):In Heat exchanger components are added to the link with small irreversible damage, thereby changing the topological architecture of hydrogen fuel aircraft engines, achieving the purpose of recycling available energy and thermal management, and ultimately realizing the improvement of hydrogen fuel aircraft engine system performance. Figure 6 Given based on Analysis results show improved hydrogen fuel aircraft engine topology architecture.

[0085] according to Figure 6 The given hydrogen fuel aircraft engine topology architecture, combined with the component model of the hydrogen fuel aircraft engine, can calculate the performance comparison of the hydrogen fuel aircraft engine before and after the improved topology structure, such as Figure 7 a. Figure 7 b. Figure 7 As shown in c.

Claims

1. A hydrogen fuel aircraft engine architecture analysis method based on exergy analysis, characterized in that: The following steps are involved: Step 1: According to the physical characteristics of each component of the aircraft engine, a thermodynamic model of the aircraft engine components is constructed. With the steady-state joint working equation as a constraint, the calculation results of the total temperature T, total pressure P, fuel consumption SFC, and thrust F of the aircraft engine section are obtained through iterative calculation; Step 2: Construct the components of hydrogen fuel aircraft engines based on the energy balance equation of the stable flow system Flow model, through components Coupling flow model and thermodynamic model to realize hydrogen fuel aviation engine components Stream computing; Step 3: Set up Loss rate, efficiency, Three loss factors Evaluation indicators, based on Evaluation indicators for hydrogen fuel aircraft engine components Identify the weak links in system energy utilization based on the flow calculation results; Step 4: Based on The analysis results show that by adding heat exchanger components, the topological structure changes and comprehensive thermal management research of hydrogen fuel aircraft engines can be carried out to improve the system performance of hydrogen fuel aircraft engines.

2. A method according to claim 1 based on The hydrogen fuel aircraft engine architecture analysis method is characterized by: In step 1, the aircraft engine component-level modeling method is used to calculate the cross-sectional total temperature T, cross-sectional total pressure P, mass flow W, fuel consumption rate SFC, and thrust F parameters. The specific process includes the following steps: Step 2.1: According to the physical characteristics of each component of the aircraft engine, the thermodynamic models of the inlet, low-pressure compressor, high-pressure compressor, combustion chamber, high-pressure turbine, low-pressure turbine, inner nozzle and outer nozzle are established in sequence. When the total temperature T of the working fluid at the inlet section of the component is determined in , total pressure P in , and mass flow rate W in When the total temperature T of the working fluid at its outlet section is obtained through the thermodynamic model of the component out , total pressure P out , and mass flow rate W out ; Step 2.2: After connecting the component models in series, the airflow parameters of each component cross section are calculated according to the aero-engine gas flow path. This calculation process complies with the constraints of the steady-state joint working equation of the aero-engine. Step 2.3: Use the least squares method to solve the common working equation containing the entire aircraft engine steady-state model, and bring the mass flow W, speed N, and pressure ratio π design parameters that satisfy the common working equation into the aircraft engine steady-state model, so as to obtain the component cross-sectional parameters and thrust F and fuel consumption SFC parameters that meet the current working conditions of the aircraft engine; The calculation expression is: F=W(V-V0)+A(Ps-Ps0) (1) In the formula, V0, P s0 is the aircraft flight speed and the external atmospheric static pressure; W is the mass flow rate of the nozzle outlet section; V is the nozzle exhaust velocity; A, A 15 is the nozzle outlet cross-sectional area; P s Static pressure of nozzle exit section; Where, F is the total thrust of the aircraft engine; W f is the fuel mass flow rate.

3. A method according to claim 1 based on The hydrogen fuel aircraft engine architecture analysis method is characterized by: In step 2, based on Computational model and energy balance model of stable flow system, construction of various components of hydrogen fuel aircraft engine Flow model, through components Coupling flow model and thermodynamic model to realize hydrogen fuel aviation engine components Stream computing.

4. A method according to claim 3 based on The hydrogen fuel aircraft engine architecture analysis method is characterized by: The details are as follows: 1): Determine the reference environment model, including reference environment temperature, reference environment pressure, and environment gas molar component parameters; 2): Build Value calculation model, total E contains physical E PH and Chemistry E CH Two items, Among them, physics E PH The calculation expression is: E PH =W[h-h0-T0(s-s0)] (3) Where W is the mass flow rate; h and s are the specific enthalpy and specific entropy of the system working fluid in a certain state; h0, s0 and T0 are the specific enthalpy, specific entropy and temperature of the reference environment. Chemical E CH The calculation expression is: In the formula, the first term on the right represents the chemical reaction produced by the chemical reaction when the system reaches a free equilibrium state. ; The second term is the chemical diffusion caused by the diffusion of chemical substances due to concentration differences , System Total E for Chemistry and physics The calculation expression is: E=E PH +E CH (5) 3): Based on the energy balance principle, the energy balance equation of the stable flow system is constructed, and its expression is: In the formula, E i For inflow system ; E e For outflow system ; W is the mass flow rate of the working fluid flowing through the system; h1, s1 and V1 are the enthalpy, entropy and relative velocity of the inflowing working fluid; h2, s2 and V2 are the enthalpy, entropy and relative velocity of the outflowing working fluid, T0 is the reference ambient temperature, and T is the temperature of the working fluid at a certain moment; 4): Based on the above The calculation model and the energy balance equation of the stable flow system are used to establish the internal components of the aircraft engine. Stream computing model, components The stream computing model is as follows: Intake Stream computing model: I Inlet =E inInlet -E outInlet (7) In the formula, I Inlet For air intake components Loss; E inInlet With E outInlet is the sum of the inlet and outlet air flows value; Compressor Stream computing model: THE Compressor =And inCompressor -AND outCompressor +L C (8) In the formula, I Conmpressor For compressor parts Loss; E inConmpressor With E outConmpressor The total air flow at the compressor inlet and outlet Value; L C is the power consumption of the compressor components; Combustion Chamber Stream computing model: I Combustor =∑E inCombustor -E outCombustor (9) In the formula, I Combustor It's the combustion chamber Loss; ∑E inCombustor is the total amount of material entering the combustion chamber Value, including air and fuel; E outCombustor is the total amount of material at the combustion chamber outlet value, its component is gas; turbine Stream computing model: THE Turbine =And inTurbine -AND outTurbine -THE T (10) In the formula, I Turbine For turbine components Loss; E inTurbine With E outTurbine is the total of the turbine component inlet and outlet airflow Value; L T It is the shaft work output by the turbine. Nozzle Stream computing model: I Nozzle =E inNozzle -E outNozzle (11) In the formula, I Nozzle For nozzle parts Loss; E inNozzle With E outNozzle is the total flow rate at the nozzle inlet and outlet , for physics With kinetic energy sum.

5. A method according to claim 1 based on The hydrogen fuel aircraft engine architecture analysis method is characterized by: In step 3, Efficiency k , Loss rate θ k , Loss coefficient ξ k Three Evaluation index, its calculation expression is as follows: Efficiency k : In the formula, the subscript k represents a component of the system; γ k For component k Efficiency; E out,k is the output of component k Value; E in,k is the input of component k value; Loss rate θ k : In the formula, θ k For component k Loss rate; I k is the total number of components k Loss; ∑I k For the system loss; Loss coefficient ξ k : In the formula, ξ k For component k Loss rate; E in is the total number of components k loss.

6. A method according to claim 1 based on The hydrogen fuel aircraft engine architecture analysis method is characterized by: In step 4, the details are as follows: 1): Through the identification results of the energy weak links of the hydrogen fuel aircraft engine system, Conduct thermal management research on links with large losses; 2): Analysis The link with the largest loss is determined through evaluation. Consider whether to recover waste heat based on the irreversibility of the damage; 3):In Heat exchanger components are added to the links with small irreversible damage, thereby changing the topological architecture of the hydrogen fuel aircraft engine, achieving the purpose of recovering available energy and thermal management, and ultimately realizing the improvement of the performance of the hydrogen fuel aircraft engine system.

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