ESDU

Validated Design and Analysis Tools for

Gas-Gas Ejectors

Francesca Iudicello

Head of Fluid Mechanics Group, ESDU - IHS

Francesca.Iudicello@ihs.com

ESDUWhere research meets design

Administrator사각형

Who is IHS?• In business since 1959, IHS is a leading global source of critical

information and insight for customers in a broad range of industries.

• Its customer product and service solutions span four areas of

business information: Energy, Product Lifecycle, Security and

Environment.

IHS helps governments, multi-national and smaller companies and

technical professionals in more than 180 countries.

There are 3,800 IHS employees in 22 countries.

From design engineering to maintenance and disposition

From explorationto consumption

Products and

Solutions spanning

four areas of

critical information

From risk assessment to supporting military operations

From material selection and management to hazardous waste disposal and emissions

IHS supports its customers in their innovative and successful

strategic and technical decision making

Security

Product

LifecycleEnergy

Environment

ESDU – History

• ESDU started life in 1940 as the Technical Department of the

Royal Aeronautical Society (RAeS) to capture and validate

design data and methods in aerospace engineering.

• It evolved into the Engineering Sciences Data Unit to

provide engineering design data and methods for

aeronautical engineers.

• It later expanded to include aerospace, mechanical,

structural, and process engineering information.

• ESDU was acquired by IHS in 1997.

ESDU Standard Design Methods

• The ESDU collection is a compendium of standard requirements,

techniques, methods, software & engineering data covering a

wide range of engineering disciplines.

• Each ESDU tool is the product of a comprehensive validation

process by a wide range of independent subject matter experts

drawn from industry, research organizations and academia.

• In addition to access to the ESDU analytical tools and software,

users also get access to our team of experts to give additional

help and guidance in the use and interpretation of the ESDU

tools.

Key Customers Include…

Commercial Military Space Helicopter

Regional Business Missile Engine

ESDU Engineering Disciplines

or Series

• Aerodynamics

• Aircraft Noise

• Aircraft Performance

• Composites

• Flight Dynamics

• Fluid Mechanics

• Fracture Mechanics

• Fatigue

• Heat Transfer

• Mechanisms

• Metallic Material Properties

• Structures

• Stress and Strength

• Transonic Aerodynamics

• Vibration and Acoustic Fatigue

• Wind Engineering

Companies on ESDU Technical Committees

ESDU - Fluid Mechanics Series

• 80 Data Items in 20 Volumes:

– Jet flow, mean values

– Straight pipes, bends, branches, junctions, coils, bends

– Duct fittings and equipment – flow-meters, valves, orifice plates

– Ejectors and jet pumps

– Duct expansions, duct contractions

– Rotating machinery

– Two-phase flow

– Non-Newtonian flow

– Fans and Pumps

– Noise in air-conditioning systems, fluid transients in pipes and

tunnels, pipeline vibrations

– CFD Guides

ESDU Internal Flow Panel

• Dr J.A. Eaton (Chairman) - National University of Ireland, Galway

• Dr N. Baines - Concepts NREC

• Mr D.A. Campbell - Independent, (ex Rolls-Royce)

• Prof. P.R.N. Childs - Imperial College

• Mr S. Curzons - Rolls-Royce plc

• Mr B.C. Freeman - Independent

• Dr W.R. Geddes - National Nuclear Laboratory

• Dr S. Gilham - Atkins

• Dr B. Haller - Alstom Power

• Mr G. Hassall - Dantec Dynamics Ltd

• Dr I. Jones - ANSYS Europe

• Dr A. Johnson - Schlumberger Cambridge Research

• Dr P.J.G. Long - Cambridge University

• Prof. L. Lu - Beijing University of Aeronautics and Astronautics

• Dr Y. Sinai - HeatandFlow Consultancy Ltd

• Dr K.M. Tham - Siemens Energy Inc.

• Dr J.T. Turner - University of Manchester

ESDU Design and Performance Methods for Ejectors and Jet Pumps

Typical ejector configuration

Other ejector configurations

Ejectors and Jet Pumps for Compressible Gas Flow: ESDU 92042 and A9242

• For design or performance assessment of ejectors (or jet pumps) in which the primary and secondary flows may be of the same or of different non-reacting gases.

• Three methodologies available (two design methods):

– Quick design method

– Detailed design method

– Performance prediction method

Quick Design Method

• Based on empirical data from typical air-air single nozzle ejectors

• Requires minimum input data:

– selection of entry and exit pressures, temperatures, mass flow rate and

geometry

• Calculates primary nozzle and exit dimensions.

• Restricted to:

– ejectors with constant area mixing

– Air-air ejectors

Detailed Design Method

• Based on one-dimensional flow theory

• Enables the assessment of internal losses

• Can be applied to multiple nozzle and annular nozzle designs

• In addition to the input for the quick method, it requires the loss factors in the primary and secondary nozzles, mixing duct and contraction or diffuser) and acceptable maximum design values for four parameters

• Calculates geometry and flow conditions throughout the ejector

Performance Prediction Method

• For an existing design

• Based on one-dimensional flow theory

• Calculates flow conditions throughout the ejector for a given geometry, loss factors and entry flow parameters

• Can be applied to multiple nozzle and annular nozzle designs

• Calculates conditions throughout the ejector

ESDU program A9242

• Main Form Input Data:

– Title, units system, method

– Gas properties

– Ejector geometry

– Flow conditions

– About the program

– Files

General Input for Design

• Inlet primary and secondary gas properties:

– specific heat capacity ratio, γ

– Gas constant, R

• Flow conditions:

– Inlet (primary and secondary) and outlet total pressures, pt

– Inlet (primary and secondary) and outlet mass flow rates, m

– Inlet (primary and secondary) temperature, T

– Upper limits for primary pressure and secondary Mach number

• Geometry

– Mixing duct:

• length to diameter ratio ((S+L)/d4), area ratio (A4/Ae), maximum area ratio

– Contraction/diffuser:

• Exit diameter, wall angle

• Maximum area ratio A5/A4

• Loss factors for the primary nozzle

Example for Design Methods• Requirements:

– discharge a total mass flow of air at pt= 150 kN/m2 absolute to a duct of

d5=0.38 m diameter.

• Inlet primary temperature: – 60°C (333.15 K)

• Inlet secondary temperatures: – 15°C (288.15 K)

• Primary air supply of 5 kg/s at 700 kN/m2 absolute

• Convergent-divergent primary nozzle

• There are no restrictions on the size of the ejector.

Quick Design Input/Output

• Input variables:

– absolute total pressure, pt

– mass flow rate, m

• Input combinations:

Either (i) enter 2 of 3 pressures and 2 of 3 mass flow rates,

or (ii) enter 2 of 3 pressures and 1 of 3 mass flow rates,

or (iii) enter 1 of 3 pressures and 2 of 3 mass flow rates.

• Output:

– Secondary entry pressure

– Primary nozzle geometry: exit and throat areas

– Mixing duct area

– Diffuser exit area, A5

– Diffuser length, Ld

– Diffuser length/diameter ratio, Ld /D4

Detailed Design Input/Output • Additional input:

– gas properties

– primary nozzle discharge coefficient

– mixing duct loss factor

– diffuser pressure recovery

– secondary inlet efficiency

– mixing duct area ratio and limit

– primary nozzle total pressure limit

– secondary inlet Mach number limit

– exit duct area ratio

• Additional output, Mach numbers at:

– primary nozzle exit,

– secondary stream at exit plane,

– mixing duct exit plane,

– contraction/diffuser exit plane

Performance Prediction Input

• gas properties

• primary nozzle discharge coefficient

• mixing duct loss factor

• diffuser pressure recovery

• secondary inlet efficiency

• mixing duct area ratio

• primary nozzle throat diameter

• primary nozzle exit diameter

• mixing duct exit diameter

• contraction/diffuser exit diameter

• mixing duct length to diameter ratio

• contraction or diffuser length to diameter ratio

• primary and secondary entry total pressure

• primary and secondary entry total temperature

Performance Prediction Output

• Primary nozzle exit area to throat area ratio, throat area, exit area

• Mixing duct cross-sectional area

• Contraction or diffuser exit area

• Primary nozzle throat to mixing duct area ratio

• Mixing duct area to primary nozzle exit ratio

• Diffuser area ratio

• Mixing duct length

• Diffuser (or contraction) length/diameter ratio

• Diffuser length

• Primary nozzle exit Mach number

• Exit pressure

• Primary, secondary and discharge mass flow rates

• Primary to exit, secondary to exit, primary to secondary pressure ratios

• Secondary to primary mass flow ratio

• Mach numbers at secondary nozzle exit, mixing duct exit and diffuser exit