CN103017852A - Method for measuring quantity of liquid propellant in storage tank - Google Patents

Abstract

The invention provides a method for measuring a quantity of a liquid propellant in a storage tank, which comprises the following steps of: step S1, measuring initial pressures and temperatures of the storage tank and a gas cylinder and forecasting an initial gas volume V0 and a quantity m10 of the residual liquid propellant in the storage tank by utilizing a propellant quantity static measurement method; step S2, establishing a heat and mass transfer mathematical model used in the pressurizing process of a storage tank open system and carrying out simulation calculation by utilizing the measured initial conditions so as to obtain a relation that a gas phase temperature and a gas phase pressure are changed with time and the propellant quantity in the storage tank; step S3, injecting pressurizing gas into the storage tank by the gas cylinder, enabling holding time to be consistent with simulation calculation time and keeping a pipeline having excellent sealing performance; step S4, measuring a gas pressure and a gas temperature of the gas part in the storage tank at a preset moment and comparing the gas pressure and the gas temperature with a simulation result; and step S5, fitting actual propellant flow according to the simulation result and an experimental result and calculating the quantity of the residual propellant in the storage tank at any moment by a formula under the condition of the known initial propellant quantity.

Description

Tank liquid propellant measuring method

Technical field

The present invention relates to Tank of Spacecraft and advance the dosage measurement field, in particular to a kind of tank liquid propellant measuring method.

Background technology

Advance dosage information all to be of great importance in space flight and aviation and low temperature field, life-span that how much is directly connected to spacecraft of spacecraft liquid propellant amount and to the arrangement of spacecraft task, therefore in the space flight mission period, as far as possible accurately estimate and advance dosage in the tank.For example, in the survey of deep space task, when aircraft was in the unpowered earth free flight stage and leaves Earth's orbit, engine will restart once, even repeatedly.Therefore, must guarantee has enough propellants before carrying out detection mission, the orbit maneuver ability of aircraft is estimated accurately, thereby made a kind of high precision, liquid propellant measuring method stable, that be used under the microgravity condition reliably become key.

At the rail loading technique, need to measure exactly the liquid propellant amount for the space liquid propellant of present rise equally, thereby determine on opportunity of rail filling and need the propelling dosage of filling; Advance dosage in the rail testing result, directly impact provides the selection of spacecraft of filling-up service and the reaction time of emission coefficient.Particularly for " multi-to-multi " scene in rail filling task, be that a plurality of Servicing spacecrafts are implemented in the rail filling to a plurality of passive space vehicles, the accurate testing result of propelling dosage can be used as the input quantity in rail filling path optimization, provides reliable reference for optimizing in rail filling path.

It is to advance dosage measurement mainly for static sealing on the satellite that tradition advances Dosimetry, and measuring accuracy is not high yet, the method that is successfully applied at present on the satellite comprises bookkeeping method and gas law method, the former is subject to the cumulative errors impact, measuring accuracy reduces gradually, and the latter is not had an applicability under the tank leak case.The use of these methods also has many restrictive conditions: the one, the tank type there is requirement, and can only be used for the barrier film tank such as the radioactivity survey method; The 2nd, the propellant type has requirement, can not be applied to cryogenic propellant such as calorimetry; The 3rd, need to apply extra disturbance to the tank system, need to increase propulsion system such as hydrodynamic method the tank system is applied certain acceleration, obtain regular liquid level and measure; The 4th, measuring method is subject to the modeling accuracy impact, the fluid dynamics behavior all has more different with ground under microgravity condition, the tank system is applied certain heat can have the thermal stratification phenomenon, the light path that optical method applies the light walking has very large uncertainty, in addition, need also that the measurement mechanism quality is light, volume is little, many-sided restrictive condition such as low in energy consumption, good reproducibility, these restrictive conditions often cause measuring difficulty and even can not survey.And for the tank open system that has fluid to flow out, also not having at present preferably, method realizes it is advanced dosage Real-time Measuring amount.Repeatedly light a fire for the rocket engine of the work of restarting for needs, real-time estimate advances dosage to guarantee that the fuel supply with abundance is the reliable guarantee of its normal operation in the tank.

Summary of the invention

The present invention aims to provide the tank liquid propellant measuring method that advances dosage in a kind of high-precision real-time measurement tank, have external pressurization gas to enter tank to solve in the prior art, when having again simultaneously propellant to flow out in the tank residual propellant amount can't kinetic measurement problem.

The invention provides a kind of tank liquid propellant measuring method, may further comprise the steps: step S1: the original pressure by the gas part in the tank pressure transducer measurement tank, utilize gas part initial temperature and tank wall initial temperature in the tank temperature sensor measurement tank; By original pressure and initial temperature in storage pressure sensor and the gas cylinder temperature sensor measurement gas cylinder; Utilize and advance the dosage static measurement method to estimate initial gas volume V ₀Advance dosage m with remaining liq in the tank _L0Step S2: set up the heat and mass mathematical model of tank open system pressurization, utilize to survey measured starting condition and carry out simulation calculation, obtain gas phase temperature, gaseous pressure and advance the variation relation of dosage in time with in the tank; Step S3: inject pressurization gas by gas cylinder to tank, hold time and the analogue simulation time consistency, and keep pipeline to have good sealing property; Step S4: measure gaseous tension and the gas temperature of the gas part in the default constantly tank, and compare with simulation result; Step S5: according to simulation result and experimental result, match is actual propellant flow rate out, in the situation of known initial propulsion dosage, passes through formula

Calculate the residual propellant amount in any moment tank.

Further, in step S2, mathematical model comprises: wherein, subscript g represents gas phase, and subscript l is liquid phase; The gas phase continuity equation:

The liquid phase continuity equation:

M wherein _G1Be pressurization gas quality in the gas phase, m _G2Be propellant vapor quality in the gas phase, m _lBe liquid propellant quality, m _L0Be the original liquid quality of utilizing static propellant amount to measure; Pressurization gas mass flow equation: work as P/P _H＞0.528 o'clock, pressurization gas was subcritical flowing, and has:

Work as P/P _H≤ 0.528 o'clock, pressurization gas was overcritical flowing, and has:

Wherein, α is coefficient of flow, and P is gas phase stagnation pressure in the tank, P _HBe pressurization gas dividing potential drop in the tank, T _HBe pressurization gas temperature, A _MinBe the restricting element area, k is adiabatic exponent, and R is the standard molar specific heat, M ₁Be the pressurization gas molal weight; Liquid oxygen surface volatilization mass transfer equation:

Wherein, K _mBe mass transfer coefficient, A is that mass transfer surfaces is long-pending, P _SatBe liquid oxygen saturated vapour pressure, P ₂Be propellant partial vapour pressure in the gas-phase space, M ₂Be propellant steam molal weight, T _SatBe the propellant saturation temperature; Energy conservation equation: Δ Q=Δ E+ ∑ h _InΔ m _In, in the formula, Δ Q is gas-phase space to liquid propellant surface and vessel surface heat transfer capacity, Δ E is the change of internal energy of gas-phase space, Δ m _InFor flowing into the gaseous mass of gas-phase space, h _InFor flowing into the enthalpy of gas-phase space; The heat transfer equation of container wall and gas-phase space comprises: the tank wall amount of stored heat of gas-phase space is: Δ Q _w=M _W1C _w(T _{W, τ+Δ τ}-T _{W, τ})+M _W2C _w(T _{W, τ+Δ τ}-T ₀); The heat exchange amount of gas and tank wall is: Δ Q _f=α ₁F ₁(T-T _{W, τ+Δ τ})+α ₂F ₂(T-T ₀); Wherein, C _wBe tank wall specific heat, M _W1The quality of the tank wall that constantly contacts with gas-phase space for τ, M _W2Be τ+Δ τ tank quality corresponding to tank area that come out because the outflow of liquid propellant and liquid oxygen volatilize constantly, T _{W, τ+Δ τ}Be τ+Δ τ moment tank wall surface temperature, T ₀Be the propellant body temperature, T is the gas-phase space temperature, F ₁Be τ tank surface area constantly, F ₂Be the tank surface area that τ+Δ τ comes out owing to outflow and the volatilization of liquid propellant constantly, Δ Q is arranged _f=Δ Q _w

Further, in step S1, advancing the dosage static measurement method is the gas inject method; By inject the external high pressure gas of default quality to tank, change by tank temperature and pressure after measuring injection, calculate the volume of liquid propellant.

Further, in step S1, advancing the dosage static measurement method is the volume advocate approach; By making tank change preset vol, utilize aerothermodynami equation and initial final state temperature, pressure measurement data and volume excitation amplitude to calculate gas volume, calculate liquid propellant volume and quality in the tank by tank cumulative volume and fluid density again.

Further, in step S1, advancing the dosage static measurement method is the optical attenuator method; By at the tank top to the known light of tank internal emission, measure light ray energy density by the receiver that is installed in tank inside, and with the light ray energy density ratio of known light, by light ray energy density change amount and liquid the relationship between quantities, calculate liquid propellant volume or quality in the tank.

According to tank liquid propellant measuring method of the present invention, the gas cylinder that utilizes spacecraft to carry, after measuring starting condition and injecting gaseous tension and temperature behind certain gas in the tank by gas cylinder, simulation calculation, thereby simulate actual propellant flow rate, and then can measure exactly the residual propellant amount in any moment tank.Measuring method precision of the present invention is high, and need not extra device, can satisfy Tank of Spacecraft externally pressurization gas enter tank, when having again simultaneously propellant to flow out in the tank time, the requirement of the measurement residual propellant amount of real-time high-precision.

Description of drawings

The accompanying drawing that consists of the application's a part is used to provide a further understanding of the present invention, and illustrative examples of the present invention and explanation thereof are used for explaining the present invention, do not consist of improper restriction of the present invention.In the accompanying drawings:

Fig. 1 is the principle schematic according to tank liquid propellant measuring method of the present invention; And

Fig. 2 is the simulation result synoptic diagram according to tank liquid propellant measuring method of the present invention.

Embodiment

Describe below with reference to the accompanying drawings and in conjunction with the embodiments the present invention in detail.

As shown in Figure 1, tank liquid propellant measuring method provided by the invention, may further comprise the steps: step S1: by the original pressure of the gas part 3 in the tank pressure transducer 5 measurement tanks 1, gas part 3 initial temperatures and the tank 1 wall initial temperature of utilizing tank temperature sensor 6 to measure in the tanks 1; Measure gas cylinder 4 interior original pressure and initial temperatures by storage pressure sensor 5 ' and gas cylinder temperature sensor 6 '; Utilize and advance the dosage static measurement method to estimate initial gas volume V ₀Advance dosage m with remaining liq in the tank _L0Step S2: set up the heat and mass mathematical model of tank open system pressurization, utilize to survey measured starting condition and carry out simulation calculation, obtain gas phase temperature, gaseous pressure and advance the variation relation of dosage in time with in the tank; Step S3: inject pressurization gas by gas cylinder 4 to tank 1, hold time and the analogue simulation time consistency, and keep pipeline to have good sealing property; Step S4: measure gaseous tension and the gas temperature of the gas part 3 in the default constantly tank 1, and compare with simulation result; Step S5: according to simulation result and experimental result, match is actual propellant flow rate out, in the situation of known initial propulsion dosage, passes through formula Calculate the residual propellant amount in any moment tank 1.The gas cylinder that the present invention utilizes spacecraft to carry, after measuring starting condition and injecting gaseous tension and temperature behind certain gas in the tank by gas cylinder, simulation calculation, thus simulate actual propellant flow rate, and then can measure exactly the residual propellant amount in any moment tank.Measuring method precision of the present invention is high, and need not extra device, can satisfy Tank of Spacecraft externally pressurization gas enter tank, when having again simultaneously propellant to flow out in the tank time, the requirement of the measurement residual propellant amount of real-time high-precision.

Particularly, as shown in Figure 1, at first utilize pressure transducer 5 to measure the original pressure of tank 1 interior gas part 3, utilize temperature sensor 6 measurement gas parts, 3 initial temperatures and tank 1 wall initial temperature, and utilize propelling dosage high precision static measurement method to estimate initial gas volume V ₀With residual propellant amount m in the tank _L0Equally, utilize another set of pressure transducer 5 ' and temperature sensor 6 ' to measure gas cylinder 4 interior original pressure and initial temperatures;

Then set up the heat and mass mathematical model of tank open system pressurization, utilize to survey measured starting condition and carry out simulation calculation, obtain gas phase temperature, gaseous pressure and advance the variation relation of dosage in time with in the tank.

Usually, mathematical model comprises heat transfer equation between continuity equation, energy conservation equation, gas phase and the tank wall of gas phase and liquid phase, the heat and mass equation between gas-liquid, actual gas physical property equation etc.; Simultaneously, as shown in Figure 2, set pre-supercharging 9, stop supercharging 10 and keep time of supercharging 11, the time reference during as experiment measuring.Subscript g, l represent respectively gas phase and liquid phase, and 1,2 represents respectively pressurization gas and the propellant steam of gas phase, and deriving, it is as follows to set up process.

1) continuity equation is:

M wherein _G1Be pressurization gas quality in the gas phase, m _G2Be propellant vapor quality in the gas phase, m _lBe liquid propellant quality, m _L0Be the original liquid quality of utilizing static propellant amount to measure.

2) pressurization gas mass flow equation: work as P/P _H＞0.528 o'clock, pressurization gas was subcritical flowing, and has:

$\frac{{\mathrm{<figure-callout\; id="1"\; label="dm\; g"\; filenames="HDA00002675452800011.png"\; state="\{\{state\}\}">dm</figure-callout>}}_g}{\mathrm{d\&tau;}}=\mathrm{\&alpha;}{P}_H{A}_{\min }{\left\{\frac{2k}{k-1}\frac{{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HDA00002675452800011.png"\; state="\{\{state\}\}">M</figure-callout>}}_1}{{\mathrm{RT}}_H}\right[{\left(\frac{P}{P_H}\right)}^{\frac{2}{k}}-{\left(\frac{P}{P_H}\right)}^{\frac{k+1}{k}}\left]\right\}}^{0.5}---\left(3\right)$

Work as P/P _H≤ 0.528 o'clock, pressurization gas was overcritical flowing, and has:

$\frac{{\mathrm{<figure-callout\; id="1"\; label="dm\; g"\; filenames="HDA00002675452800011.png"\; state="\{\{state\}\}">dm</figure-callout>}}_g}{\mathrm{d\&tau;}}={\left(\frac{2}{k+1}\right)}^{\frac{1}{k-1}}\mathrm{\&alpha;}{P}_H{A}_{\min }{\left(\frac{2k}{k-1}\frac{{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HDA00002675452800011.png"\; state="\{\{state\}\}">M</figure-callout>}}_1}{{\mathrm{RT}}_H}\right)}^{0.5}---\left(4\right)$

In the formula, α is coefficient of flow, and P is gas phase stagnation pressure in the tank, P _HBe pressurization gas dividing potential drop in the tank, T _HBe pressurization gas temperature, A _MinBe the restricting element area, k is adiabatic exponent, and R is the standard molar specific heat, M ₁Be the pressurization gas molal weight.

3) liquid oxygen surface volatilization mass transfer equation is:

$\frac{{\mathrm{<figure-callout\; id="2"\; label="dm"\; filenames="HDA00002675452800011.png"\; state="\{\{state\}\}">dm</figure-callout>}}_2}{\mathrm{d\&tau;}}=\frac{K_{m}A(P_{\mathrm{sat}}-P_2){\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA00002675452800011.png"\; state="\{\{state\}\}">M</figure-callout>}}_2}{{\mathrm{RH}}_{\mathrm{sat}}}---\left(5\right)$

In the formula, K _mBe mass transfer coefficient, A is that mass transfer surfaces is long-pending, P _SatBe liquid oxygen saturated vapour pressure, P ₂Be propellant partial vapour pressure in the gas-phase space, M ₂Be propellant steam molal weight, T _SatBe the propellant saturation temperature.

In following formula, mass transfer coefficient K _mCalculate and get by following formula:

K _m=0.0292u ^0.78X ^-0.11Sc ^-0.67 （6）

Wherein: u is liquid propellant airflow on surface flow velocity; X is liquid propellant surface mass transfer characteristic yardstick; Sc is the Schmidt number,

Wherein υ is kinematic viscosity coefficient, and D is coefficient of diffusion.

If liquid propellant is liquid oxygen, then the saturation temperature on the liquid oxygen surface saturation pressure corresponding with it is:

lgP _sat=9.13427-374.5/T _sat （7）

There is intrinsic relational expression in the saturation temperature of the liquid propellant saturation pressure corresponding with it.

4) energy conservation equation is

ΔQ=ΔE+∑h _in·Δm _in （8）

In the formula, Δ Q is that gas-phase space is to liquid propellant surface and vessel surface heat transfer capacity; Δ E is the change of internal energy of gas-phase space; Δ m _InFor flowing into the gaseous mass of gas-phase space; h _InFor flowing into the enthalpy of gas-phase space.

5) heat transfer of container wall and gas-phase space:

The tank wall amount of stored heat of gas-phase space is: Δ Q _w=M _W1C _w(T _{W, τ+Δ τ}-T _{W, τ})+M _W2C _w(T _{W, τ+Δ τ}-T ₀) (9)

The heat exchange amount of gas and tank wall is: Δ Q _f=α ₁F ₁(T-T _{W, τ+Δ τ})+α ₂F ₂(T-T ₀) (10)

More than in two formulas, C _wBe tank wall specific heat, M _W1The quality of the tank wall that constantly contacts with gas-phase space for τ; M _W2Be τ+Δ τ tank quality corresponding to tank area that come out because the outflow of liquid propellant and liquid oxygen volatilize constantly; T _{W, τ+Δ τ}Be τ+Δ τ moment tank wall surface temperature, T ₀Be the propellant body temperature, T is the gas-phase space temperature, F ₁Be τ tank surface area constantly, F ₂Be the tank surface area that τ+Δ τ comes out owing to outflow and the volatilization of liquid propellant constantly, Δ Q is obviously arranged _f=Δ Q _w

6) the physical property equation of actual gas

P ₁V=Z ₁m _g1RTM _g1,P ₂V=Z ₂m _g2RTM _g2 （11）

In the formula: Z ₁, Z ₂It is respectively the compressibility factor of pressurization gas and propellant steam; R is universal gas constant; T is gas-phase space temperature in the tank; M _G1, M _G2It is respectively the molal weight of pressurization gas and propellant steam.

Formula (1) to (11) is put in order abbreviation, obtain gas phase temperature, gaseous pressure and advance the variation relation of dosage in time with in the tank.

Then, as shown in Figure 2, pressurization comprises pre-supercharging 9, stop supercharging 10 and keep supercharging 11 three phases, pre-pressurization stages 9 begins after the primary data that measures tank 1 and gas cylinder 4, there is not propellant to flow out by gas cylinder to tank injecting gas and tank below during pre-supercharging, by the time after gas-phase space pressure arrives predetermined pressure in the tank, gas cylinder stops to the tank aerating, enter and stop pressurization stages 10, leave standstill a period of time (the general time is shorter), keeping the existing external pressurization gas of pressurization stages 11 tanks to enter also has propellant to flow out with constant rate, and different propellants flows out speed will produce different gaseous pressure growth curves.Pass through gas cylinder 4 during experiment to tank 1 interior injection pressurization gas, hold time and the analogue simulation time consistency; Keep pipeline to have good sealing property; And measure the pressure and temperature of presetting the gas part 3 in the moment tank 1, and compare with simulation result.

According to simulation result and experimental result, simulate actual propellant flow rate, in the situation of known initial propulsion dosage, pass through formula

Can predict the surplus in any moment tank.

The present invention advances the used method of dosage static measurement can be one of following technology to tank:

1, gas inject method: the gas that is injected certain mass by external high pressure gas by the connection valve pipeline to tank, in tank, produce the arousal effect that pressure increases, tank temperature variation with temperature sensor measurement excitation generation, measure the gas pressure change that excitation produces with pressure transducer, obtain the volume of liquid propellant.This method can take full advantage of the gas cylinder of spacecraft self.

2, volume advocate approach: the volume telescopic variation that the tank system is applied certain form according to the volume exciting bank, consider the approximate incompressibility of liquid, the volume change that applies is carried by gas fully, utilize aerothermodynami equation and initial final state temperature, pressure measurement data and volume excitation amplitude to calculate gas volume, calculate liquid propellant volume and quality in the case by tank cumulative volume and fluid density again.

3, optical attenuator method: launch known light at the tank top in tank, light is passed through the many times reflection of tank wall simultaneously by liquid absorption, and the last energy density of light in any position of tank wall is consistent.By being installed in the receiver of tank wall, can measure light ray energy density, luminous energy density known during with emission relatively can obtain its change amount, and the change of light ray energy density is relevant with amount of liquid, therefore can calculate liquid propellant volume or quality in the tank.

As can be seen from the above description, the above embodiments of the present invention have realized following technique effect:

According to tank liquid propellant measuring method of the present invention, the gas cylinder that utilizes spacecraft to carry, after measuring starting condition and injecting gaseous tension and temperature behind certain gas in the tank by gas cylinder, simulation calculation, thereby simulate actual propellant flow rate, and then can measure exactly the residual propellant amount in any moment tank.Measuring method precision of the present invention is high, and need not extra device, can satisfy Tank of Spacecraft externally pressurization gas enter tank, when having again simultaneously propellant to flow out in the tank time, the requirement of the measurement residual propellant amount of real-time high-precision.

The above is the preferred embodiments of the present invention only, is not limited to the present invention, and for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (5)

1. a tank liquid propellant measuring method is characterized in that, may further comprise the steps:

Step S1: measure the partly original pressure of (3) of the interior gas of tank (1) by tank pressure transducer (5), utilize tank temperature sensor (6) to measure described tank (1) interior gas part (3) initial temperature and described tank (1) wall initial temperature; Measure the interior original pressure of gas cylinder (4) and initial temperature by storage pressure sensor (5 ') and gas cylinder temperature sensor (6 '); Utilize and advance the dosage static measurement method to estimate initial gas volume v ₀Advance dosage m with remaining liq in the tank _L0

Step S2: set up the heat and mass mathematical model of tank open system pressurization, utilize to survey measured starting condition and carry out simulation calculation, obtain gas phase temperature, gaseous pressure and advance the variation relation of dosage in time with in the tank;

Step S3: inject pressurization gas by described gas cylinder (4) to described tank (1), hold time and the analogue simulation time consistency, and keep pipeline to have good sealing property;

Step S4: measure gaseous tension and the gas temperature of the gas part (3) in the default constantly tank (1), and compare with simulation result;

Step S5: according to simulation result and experimental result, match is actual propellant flow rate out, in the situation of known initial propulsion dosage, passes through formula Calculate the residual propellant amount in the described tank of any moment (1).

2. tank liquid propellant measuring method according to claim 1 is characterized in that, in described step S2, described mathematical model comprises: wherein, subscript g represents gas phase, and subscript l is liquid phase;

The gas phase continuity equation: $\frac{{\mathrm{dm}}_g}{\mathrm{d\&tau;}}=\frac{{\mathrm{dm}}_{g1}}{\mathrm{d\&tau;}}+\frac{{\mathrm{dm}}_{g2}}{\mathrm{d\&tau;}};$

The liquid phase continuity equation: $\frac{{\mathrm{dm}}_1}{\mathrm{d\&tau;}}=\frac{m_{10}-m_1}{\mathrm{d\&tau;}};$

M wherein _G1Be pressurization gas quality in the gas phase, m _G2Be propellant vapor quality in the gas phase, m _lBe liquid propellant quality, m _L0Be the original liquid quality of utilizing static propellant amount to measure;

The pressurization gas mass flow equation:

Work as P/P _H＞0.528 o'clock, pressurization gas was subcritical flowing, and has:

$\frac{{\mathrm{dm}}_{g1}}{\mathrm{d\&tau;}}=\mathrm{\&alpha;}{P}_H{A}_{\min }{\left\{\frac{2k}{k-1}\frac{M_1}{{\mathrm{RT}}_H}\right[{\left(\frac{P}{P_H}\right)}^{\frac{2}{k}}-{\left(\frac{P}{P_H}\right)}^{\frac{k+1}{k}}\left]\right\}}^{0.5};$

Work as P/P _H≤ 0.528 o'clock, pressurization gas was overcritical flowing, and has:

Wherein, α is coefficient of flow, and P is gas phase stagnation pressure in the tank, P _HBe pressurization gas dividing potential drop in the tank, T _HBe pressurization gas temperature, A _MinBe the restricting element area, k is adiabatic exponent, and R is the standard molar specific heat, M ₁Be the pressurization gas molal weight;

Liquid oxygen surface volatilization mass transfer equation:

Wherein, K _mBe mass transfer coefficient, A is that mass transfer surfaces is long-pending, P _SatBe liquid oxygen saturated vapour pressure, P ₂Be propellant partial vapour pressure in the gas-phase space, M ₂Be propellant steam molal weight, T _SatBe the propellant saturation temperature;

Energy conservation equation: Δ Q=Δ E+ ∑ h _InΔ m _In, in the formula, Δ Q is gas-phase space to liquid propellant surface and vessel surface heat transfer capacity, Δ E is the change of internal energy of gas-phase space, Δ m _InFor flowing into the gaseous mass of gas-phase space, h _InFor flowing into the enthalpy of gas-phase space;

The heat transfer equation of container wall and gas-phase space comprises:

The tank wall amount of stored heat of gas-phase space is: Δ Q _w=M _W1C _w(T _{W, τ+Δ τ}-T _{W, τ})+M _W2C _w(T _{W, τ+Δ τ}-T ₀);

The heat exchange amount of gas and tank wall is: Δ Q _f=α ₁F ₁(T-T _{W, τ+Δ τ})+α ₂F ₂(T-T ₀);

Wherein, C _wBe tank wall specific heat, M _W1The quality of the tank wall that constantly contacts with gas-phase space for τ, M _W2Be τ+Δ τ tank quality corresponding to tank area that come out because the outflow of liquid propellant and liquid oxygen volatilize constantly, T _{W, τ+Δ τ}Be τ+Δ τ moment tank wall surface temperature, T ₀Be the propellant body temperature, T is the gas-phase space temperature, F ₁Be τ tank surface area constantly, F ₂Be the tank surface area that τ+Δ τ comes out owing to outflow and the volatilization of liquid propellant constantly, Δ Q is arranged _f=Δ Q _w

3. tank liquid propellant measuring method according to claim 1 is characterized in that, in described step S1, described propelling dosage static measurement method is the gas inject method;

By inject the external high pressure gas of default quality to described tank (1), change by tank temperature and pressure after measuring injection, calculate the volume of liquid propellant.

4. tank liquid propellant measuring method according to claim 1 is characterized in that, in described step S1, described propelling dosage static measurement method is the volume advocate approach;

By making described tank (1) change preset vol, utilize aerothermodynami equation and initial final state temperature, pressure measurement data and volume excitation amplitude to calculate gas volume, calculate the interior liquid propellant volume of described tank (1) and quality by tank cumulative volume and fluid density again.

5. tank liquid propellant measuring method according to claim 1 is characterized in that, in described step S1, described propelling dosage static measurement method is the optical attenuator method;

By at described tank (1) top to the known light of described tank (1) internal emission, measure light ray energy density by being installed in the inner receiver of described tank (1), and with the light ray energy density ratio of known light, by light ray energy density change amount and liquid the relationship between quantities, calculate the interior liquid propellant volume of described tank (1) or quality.

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