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Practical examples for simulations in spray cleaning

Dr. Oliver TiedjeJörg Schieweck

Department Coating Systems and Painting TechnologyFraunhofer IPA, Stuttgart

parts2clean, Stuttgart, 22.10.2019

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Content

Introduction Fraunhofer IPA

Importance of cleaning for painting technology

Presentation of simulation models

Application examples

Source: Fraunhofer IPA

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Fraunhofer IPAwith an interdisciplinary organization

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Closed Process Chain in Paint Technology within IPA

Raw materials

Paint Paintingtechnology

Coating

Binders Pigments Additives Thinners,

solvents

Recipies Dispersion Rheology Colouration

Substrate pre-treatment

Application Drying, curing

Adhesion Corrosion

protection Durability Functionality

S i m u l a t i o n

R e s o u r c e E f f i c i e n c y

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Importance of cleaning for painting

Ensurance of paint adhesion

Cross cut

Water jet test

…

Avoiding of wettening defects

Paint compatibility test for crates etc

Avoiding of point defects (e.g. contamination by dirt)

Source: Daimler AG

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Pretreatment of work pieces for painting

Plastics

Wet chemical pretreatment

CO2-blasting

Flaming

Plasma

Metals

Shot Blasting

Dip and Spray methods

Quelle: Daimler AGSource: Agtos

Source: B + M

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Pretreatment of work pieces for painting

Important parameter

Intensity of cleaning action

Impact

Time

Chemistry

Temperature

Angle of effect

Distance

Shadows

Bailing parts

Quelle: Daimler AG

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Way simulation?

Visual support for communication

Presentation of possibilities and ideas

Comparison of different concepts

Application in design and planning

Increase of flexibility

Feasibility studies

Detection of defects

Fundamental understandings

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Aproaches for simulation

Physical base

Fluid dynamics

Empirical base

Ray tracing

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Fluid-simulation

Study for flow and watering

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Quelle: Fraunhofer IPA

Fluid-simulation

Study for flow and watering

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Source: Fraunhofer IPA

Fluid-simulation

Study for flamingSimulation

temperature

O2-conzentration

Velocity

Trial

Flaming

IR-camera

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Quelle: Fraunhofer IPA

Transfer to emperical model

Flaming

Quelle: ARENA2036, Foto: Christian Hass

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Measurement values as input: force of impact

Nozzle for full jet

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Measurement values as input: Cleaning effect

Scannen

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Measurement values as input: Velocity (LDA / PDA)

Measurement of droplet resp. jet velocity by laser Doppler anemometry

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Simulation Reinigung

Erfassen der Schattenbereiche

Quelle: Fraunhofer IPA

Anwendungsbeispiel DRS/DLS-UV

Experiment und Simulation

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ExperimentRed oil contamination

SimulationRed ~ high contamination

15 sec

30 sec

Cleaning effect during cleaning cycles

Quelle: Fraunhofer IPA

Application examples

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Inside tank cleaning

Source: heco

Source: Fraunhofer IPA

Application examples

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Source: Hammelmann

Inside tank cleaning

Application examples

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Inside tank cleaning – optimizing shadows

Application examples

Quelle: Hammelmann

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Cleaning simulation of motor block

Development of nozzle pathes

Application examples

Quelle: Fraunhofer IPA

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Application examples

Optimization by gradient methods

Quelle: Fraunhofer IPA

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Application examples

Source: AGTOS

Rotary shot blasting

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Application examples

Quelle:AGTOS

Rotary shot blasting

Ist-Zustand Optimierte Anordnung

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Evaluations

Quelle: IPA DRS

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Source: IPA DRS

Deg

ree

of

clea

nin

gD

egre

eo

f cl

ean

ing

Percentage of Surface of work piece

Percentage of Surface of work piece

Evaluations

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Training of defect detection (e.g. CAE-Training and Workshop Dresden, 17.-18. March 2020)

Increase of flexibility

Visual support

Fundamental understanding systematic development

Simulation software DRS / DSS

Short simulation time

Windows capable

Training only 2-3 days

Summary