Simulation and Validation on Vapor Core in the Impeller Center of Vapor Core Pump

Bin WangNanjing University of Aeronautics and Astronautics, ChinaSeptember 10, 2014

2nd International Conference and Exhibition on Mechanical & Aerospace Engineering September 08-10, 2014 Philadelphia, USA

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Contents

Overview of vapor core pump1

Numerical model

Governing equations and flow model

Numerical results of the vapor core

Experimental verification

Conclusions and prospects

2

3

4

5

6

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Overview of vapor core pump

Nozzle controller of a turbofan engine

VCP

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Vapor core pump

Dismantled components of VCP

Overview of vapor core pump

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Overview of vapor core pump

sevro piston throttle valve runing impeller

VCP Schematic

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Vapor core photo

blade

vapor core region

interface layer

liquid fuel

Flow media in impeller

Overview of vapor core pump

How it occurs?How could it be simulated and analized?

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Numerical model

Geometric Model of Vapor Core Pump Structure of the Impeller

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Numerical model

Opening of the inlet throttle valve

2 mm 5 mm 8 mm

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Numerical model

Grid model for numerical calculation

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Governing equations and flow model

(1) Equation for vapor-liquid mixing flow

(2) momentum conservation

(3) TF Equation for vapor volume fraction distribution

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Governing equations and flow model

i k eff k b M ki j j

kk ku G G Y S

t x x x

2

1 3 2

i effi j j

k b

ut x x x

C G C G C R Sk k

RNG k-ε

1 23 if

3v vv l v

e vm B l

P PR P P

R

1 23 if

3v vv l v

c vm B l

P PR P P

R

1/30(3 / (4π (1 )))B v vR n

Schnerr-Sauer

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Numerical results of the vapor core

Vapor volume fraction distribution at different outlet pressure

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Numerical results of the vapor core

Performance comparison of the pump at different outlet pressure

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Numerical results of the vapor core

Vapor volume fraction distribution at different throttle opening

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Numerical results of the vapor core

Performance comparison of the pump at different throttle opening

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Experimental verification

Schematic diagram of the test system

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Experimental verification

Characteristic comparison of vapor core pump

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Conclusions and prospects

(1) The numerical simulation has a high credibility verified by the VCP prototype test. Errors of general performances between experiment and numerical simulation are less than 10% basically.

(2) Fuel vaporization has a significant influence on pump efficiency when the vapor region expands to the blade zone.

Conclusions:

Prospects:

Influence of the vapor core on the pump dynamic performance should be investigated to utilize the operating condition more effectively.Direct imaging technology should be employed for exact comparison of vapor core configuration.

Thank you for your attention