TUT3 Harms Computational Fluids and Renewables

8/13/2019 TUT3 Harms Computational Fluids and Renewables

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Applications of Computational

Fluid Dynamics (CFD) Researchin the Renewable Energy Field

Prayer helps to let both halvesof your brain talk to each other..

Department of Mechanical and MegatronicEngineering http://mecheng.sun.ac.za

University of Stellenbosch

DAAD Meeting 10thApril 2013Pretoria

Engineering Research in Renewable Energy

Thomas Harms


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Outline:(20 min.)

Introduction

Renewable Energy

Atmospheric flows

Two-phase flow

2ndgeneration biofuel

Fluid-structureinteraction

Conclusion

Shams 1 - 100 MW Parabolic Trough Plant commissioned 2013

United Arab Emirates (Masdar, Total, Abengoa Solar)

http://www.greencarcongress.com/2013/03/shams-20130317.html 27 March 2013


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50 km x 50 km ~

100 000 MWe potential~ 3 x current needs

www.eskom.co.za

Electrical Power Generation
http://www.eskom.co.za/http://www.eskom.co.za/


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SA needs to add ~1.5 GW power generation capacity annually(current demand, ageing fleet, 6 % growth target, social peace)

Some (Renewable) Energy Theses (2012):

We need sustainably (not cheaply) priced power in ample and stable

supply to optimise an investment climate for economic development

=> We need to open up all the energy streams we can also by mobilizing

independent power producers!

South Africa needs renewable power now to address peak load issues,

Germany needs renewable power now to address base load issues.

Natural and synthetic gas (Sasol) may well have to play a role here.

Renewable energy is about our resource, CO2, boosting tourism, employment,

boosting science (SKA) but mostly about the success of the country now.

Renewable Energy

Vision of a Solar Chimney Field in NamibiaGreen Tower Development (Pty.) Ltd. - MD Wolf-Walter Stinnes

Amazing [amma-zing]: It is all happening in South African now!


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Stellenbosch University Solar Power Thermodynamic (SUNSPOT)

CycleProfessor Detlev Krger 2008

Renewable Energy


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What is CFD?

Flow field simulations,

derived from the assembly

of inter-dependent solutions of

equations of natural laws,by application to e.g. millions

(computers are essential)

of subdivision (e.g. finite volumes)

of the space examined.

Applications of CFD

Eugne Joubert, MScEng, 2010

Control Volume Types

Sewis van Zyl,

PhD(Eng), 2012


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Atmospheric Flow Modeling

Jrg Schlaich, The Solar Chimney,

(Das Aufwindkraftwerk), Edition Axel Menges,

Stuttgart 1995,German version 1994.


8/35Solar chimney plant, Manzanares, Spain (1981-1989)[solar to electric efficiency ~ 2 %]



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500 km3

computational

domain

Rhydar Harris MScEng(2004)


Research Objective:

Establish a model for sub-meteorological

scale conditions (no cross winds) to help

to detect possible problem conditions

for plant operation


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500 km3

computational

domain


CFD (CFX 4-4): axi-symmetric model



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AtmosphericPhysics Troposphere

Buoyant plumes,

thermals Water vapor

Compressibility

Thermal profiles

Low viscosity

Large scales

Coriolis forces

11 km

transient, unstable,

unpredictable puffs condensation, thermal

variable density

vary throughout the

day highly turbulent, very

large to small scales

vertical rotationalwind



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Streamlines at collector inlet




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Desert Ecological Research and Training Centre Gobabeb

(Google

Imagery, 2011Teuns Cloete - BEng)




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Cobus PieterseMScEng 2013

Verification of Monin Obukhov

atmospheric theory with CFDand experimental data.

Maintenance of a stable atmospheric

boundary layer velocity profile



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Location

of Masts

Kanas

Oranjemund

MTC - Kashweka

MTC - Sheunye

Telecom Namibia - Kashweka

NamPower

GTRC - Sheunye

Gobabeb

Vaalgras

Klein Aub

Omatjette

Terrace Bay


Bernard Siepker (UNST) Ongoing PhD(Eng) Projects

Investigates the Namibian Wind Resource.

Bernard Siepker (UNST)Ongoing PhD(Eng) Studies

Gobabeb30 m


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Johan StanderMScEng 2010

(Wannoncott, 2007)

CFD Study to locate wind turbines

in the vicinity of the South African

research base SANAE IV in

Antarctica


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Outline:(20 min.)

Introduction

Renewable Energy

Atmospheric flows


Fluid-structure

interaction Two-phase flow

Conclusion






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Study of Airborne Sand Particle

Impingement on Photo Voltaic Panelsat Gobabeb

At the time 25 kW largest PV system in

Namibia (battery storage diesel hybrid)

Julian CloeteBEng - 2005

Photo: Joh Henschel - 2005Harms 2005



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Sandstorm approaching Gobabeb




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UCSB

Department

of

Geology,

2005


Wind tunnel experiment


Sh 1 100 MW P b li T h Pl t i i d 2013


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Outline:(20 min.)

Introduction

Renewable Energy

Atmospheric flows

Two-phase flow


Fluid-structureinteraction

Conclusion






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Two-phase Flow

Evacuated Tube

Receiver (with

selective coating)Synthetic oil heat transfer

fluid - does not boil 400 C

Alternative direct solar steam

(DISS) generation plant -

one commercial plant to date

Boiling process has not been

successfully modelled.

Johan HeynsCSIR - PhD(Eng) 2013

improved liquid- compressible

gas interface capturing.

Fine Wilms Postdoc 2013/14/16 will investigate boiling heat transfer


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Globalspec 2012

Stefan FootBEng - 2012

Two-phase Flow


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Image falling dropletJohan Heyns - CSIR, PhD(Eng) 2013

[in collaboration with Prof Arnaud MalanUCT]

Two-phase Flow

// / /


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http://www.rechargenews.com/solar/article1293523.ece 7-Apr-2013

Solarlite GmBHnear

Rostock, Germany

http://www.solarlite.de

7-Apr-2013

First Commercial Direct Solar Steam

Plant in Thailand, 5 MW, 350 C, 30 bar

Two-phase Flow

M d lli C ll l t Eth l C i
http://www.solarlite.de/http://www.solarlite.de/


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Image by Ben Mills,available on Wikipedia

http://myhydros.org/

Modelling Cellulose to Ethanol Conversion

The closed biofuel cyclehttp://www.greentechnolog.com/ Dr. J.M. van Zy lPhD(Eng ) 2012

[ in co l labo rat ion with Prof Lee Lynd (DC)

Prof Em ile van Zyl (US)]

2ndGeneration Biofuel


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Modelling Cellulose to Ethanol Conversion

Dr. J.M. van Zy lPhD(Eng ) 2012

[ in co l labo rat ion with Prof Lee Lynd (DC)Prof Em ile van Zyl (US)]

2ndGeneration Biofuel


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Fluid-structure

interaction

Heliostat PhD(Eng) Project

Thomas Roos CSIR - Ongoing

Cantilever beam penetratinginto wind tunnel PhD(Eng)

Eugne Joubert Ongoing

In collaboration with Prof

Gerhard Venter - US

OpenFOAM (CFD)

Code Aster (FEM)

Professional open

source codes

freely available on

the internet

Adhikar Hariram - MEng(Research)Ongoing In collaboration with Paul Gauch


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US Engineering Faculty New Computational Resource:

We havea cluster

but

Central receiver solar power plant Barstow California 10 MWe


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Central receiver solar power plant, Barstow, California, 10 MWe[solar to electric efficiency ~ 15 %]

Eskom plant (start construction 2014):

210 m tower, 6000 heliostats ~ 100 MWe

Neil Coetzee (1996) BEngDesign of solar power plant for SA

Dr Remar (Mech.Eng, SU) & Mike Prarie (Sandia Laboratories, USA)


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Conclusion

A renewable energy industry will help to address the short to

medium term electricity supply shortfall of Southern Africa

and, like other Mega Projects (SKA, more nuclear power plants)

create ample cutting edge high tech employment opportunities

f t h l i t i d i ti t Y d d!

Gemasolar, Seville,

Spain 20 MWe

15 h molten salt thermal storage

28 1425 MW R47 billion

19 1043 MW R28 billion

xx 1165 MW

~3725 MW by 2016++ 3200 MW by 2020

xx 1000 MW/annum

Enjoy!

TUT3 Harms Computational Fluids and Renewables

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