latif_mohamed-use of magnus effect rotors as wind turbines for solar chimney power plants

7/27/2019 Latif_Mohamed-Use of Magnus Effect Rotors as Wind Turbines for Solar Chimney Power Plants

1/34

Use of Magnus Effect Rotors asUse of Magnus Effect Rotors as

Wind Turbines for SolarWind Turbines for SolarChimney Power PlantsChimney Power Plants

Presented by:Presented by:

Mohammed Abdul Hamid Abdul LatifMohammed Abdul Hamid Abdul Latif

Advisor:Advisor:

Prof. Mohamed Amr Serag ElProf. Mohamed Amr Serag El--DinDin


2/34

OutlineOutline

IntroductionIntroduction

ObjectivesObjectives

MethodologyMethodology

ResultsResults ConclusionsConclusions

RecommendationsRecommendations AcknowledgmentsAcknowledgments


3/34

IntroductionIntroductionSolar ChimneysSolar Chimneys

Figure 1: Solar Chimney Power Plant Principle of Operation

Parameters:Parameters:

CollectorCollector

Area (Power Input)Area (Power Input) AbsorberAbsorber

Specific Heat CapacitySpecific Heat Capacity(Storage)(Storage)

TowerTower Length (Acceleration)Length (Acceleration)

Diameter (OutputDiameter (OutputVelocity)Velocity)

TurbineTurbine

Operating ConditionsOperating Conditions(Power Output)(Power Output)

Efficiency (PowerEfficiency (PowerOutput)Output)


4/34

IntroductionIntroductionSolar ChimneysSolar Chimneys

Research to Reduce Costs:Research to Reduce Costs:

Improvements in Construction:Improvements in Construction:

Solar Chimneys on Mountains.Solar Chimneys on Mountains.

Floating Solar Chimney.Floating Solar Chimney.

Cheaper TurbinesCheaper Turbines

Improvements in Performance:Improvements in Performance:

Turbine LayoutTurbine Layout

Turbine ConfigurationsTurbine Configurations


5/34

IntroductionIntroductionMagnus EffectMagnus Effect

Proposal:Proposal:

Use Magnus Effect Rotors as Turbine.Use Magnus Effect Rotors as Turbine.

Magnus Effect:Magnus Effect:

Figure 5: Effect of Increasing Cylinder rotational speed on lift force


6/34

IntroductionIntroductionMagnus EffectMagnus Effect

Applications:Applications:

Flettner ShipsFlettner Ships

Magnus GeneratorMagnus Generator

Figure 7: Turbine Utilizing

Magnus Effect

Figure 6: Flettner Ship using Magnus

rotors for thrust


7/34


Figure 8: Top View of Proposed System Figure 9: Solid model of Proposed System


8/34


Magnus Effect Rotors Vs. Airfoils:Magnus Effect Rotors Vs. Airfoils:

Manufacturing costs reductionManufacturing costs reduction

Maintenance costs reductionMaintenance costs reduction

Ease of ControlEase of Control Power ConsumptionPower Consumption


9/34

ObjectivesObjectives Investigate possibility of proposed system.Investigate possibility of proposed system.

Study input variables:Study input variables: Cylinder and disc diametersCylinder and disc diameters

Cylinder and disc rotational speedsCylinder and disc rotational speeds

Number of cylindersNumber of cylinders

Free stream velocityFree stream velocity

Identify most dominant variable and its effect on theIdentify most dominant variable and its effect on the

performance.performance.

Study performance through variables:Study performance through variables: Lift and drag forces generatedLift and drag forces generated

Pressure drop across the turbinePressure drop across the turbine

Power output.Power output.


10/34


Experimental:Experimental:

Inaccurate results due to scalingInaccurate results due to scaling

TediousTedious

ExpensiveExpensive Numerical model using Fluent:Numerical model using Fluent:

NavierNavier--Stokes EquationsStokes Equations

Finite Difference MethodFinite Difference Method


11/34


NonNon--Dimensional Analysis:Dimensional Analysis:

SimilaritySimilarity

Reduction of VariablesReduction of Variables

Input:Input:VariablesVariables CoefficientsCoefficients

Cylinder Radius (r)Cylinder Radius (r)

Disc Radius (R)Disc Radius (R)

Cylinder Tangential Velocity (Cylinder Tangential Velocity ())Disc Tangential Velocity (Disc Tangential Velocity ())

Number of Cylinders (n)Number of Cylinders (n)

Airspeed (v)Airspeed (v)

Cylinder Tangential Velocity to AirspeedCylinder Tangential Velocity to Airspeed

Ratio (Ratio (r / v) (CAR)r / v) (CAR)

Disc Tangential Velocity to AirspeedDisc Tangential Velocity to AirspeedRatio (Ratio (R / v) (DAR)R / v) (DAR)

Number of Cylinders (n)Number of Cylinders (n)

Ratio of Cylinder to Disc radii (r / R)Ratio of Cylinder to Disc radii (r / R)

Table 1: Variables and Coeffic ients used in the System


12/34


Output:Output:

Lift CoefficientLift Coefficient

Drag CoefficientDrag Coefficient

Pressure Drop CoefficientPressure Drop Coefficient

EfficiencyEfficiency

Input Variable Variations:Input Variable Variations:

Number of Cylinders (n):Number of Cylinders (n): 180180

120120

9090


13/34

MethodologyMethodology Cylinder to Disc RadiiCylinder to Disc Radii

(r / R)(r / R) 0.0040.004

0.0020.002

0.0010.001 CAR:CAR:

1.311.31

2.622.62 3.933.93

5.245.24

6.556.55

DAR:

0 0.0655

0.131

0.262

0.393

0.524

0.655


14/34



15/34


Fluent Parameters:Fluent Parameters:

Rotating Frame EquationsRotating Frame Equations

Viscosity: kViscosity: k--Turbulence Model:Turbulence Model: RobustRobust

EconomicEconomic

AccurateAccurate

Renormalization Group (RNG):Renormalization Group (RNG):

Accuracy in Swirling and Strained FlowsAccuracy in Swirling and Strained Flows Updated Values according to Analytical EquationsUpdated Values according to Analytical Equations


16/34

MethodologyMethodologyWall Treatments: Enhanced Near Wall:Wall Treatments: Enhanced Near Wall:

Accurate with flows experiencing:Accurate with flows experiencing: High Reynolds NumberHigh Reynolds Number

SwirlSwirl

Severe Pressure GradientsSevere Pressure Gradients

Solver: Segregated ImplicitSolver: Segregated Implicit Discretization Scheme: QUICKDiscretization Scheme: QUICK

High Accuracy with quadrilateral meshesHigh Accuracy with quadrilateral meshes

Pressure Discretization: PREssure STaggeringPressure Discretization: PREssure STaggeringOption (PRESTO!):Option (PRESTO!): High swirling and high speed rotating flowsHigh swirling and high speed rotating flows


17/34

MethodologyMethodology Gradient Evaluation: (Node Based Derivatives):Gradient Evaluation: (Node Based Derivatives):

Triangular or Tetrahedral Meshes Accuracy.Triangular or Tetrahedral Meshes Accuracy. PressurePressureVelocity Coupling: SemiVelocity Coupling: Semi--Implicit MethodImplicit Method

For Pressure Linked EquationsFor Pressure Linked EquationsConsistentConsistent

(SIMPLEC):(SIMPLEC): Complicated flows due to UnderComplicated flows due to Under--Relaxation.Relaxation.

Reliable with minimum computational effort.Reliable with minimum computational effort.

Termination Accuracy = 1 X 10Termination Accuracy = 1 X 10--66


18/34

MethodologyMethodology Mesh Accuracy:Mesh Accuracy:

y+ < 5y+ < 5

10 cells in viscosity10 cells in viscosity--affected nearaffected near--wall region (Rewall region (ReYY


19/34

ResultsResults Fluent Output:Fluent Output:

Relative and absolute velocity vectors and the streamlinesRelative and absolute velocity vectors and the streamlinesdepicting the flow.depicting the flow.

Static pressure distribution over the rotating cylinder.Static pressure distribution over the rotating cylinder.

Force component parallel to the free stream (radial to disc).Force component parallel to the free stream (radial to disc). Force component perpendicular to the free streamForce component perpendicular to the free stream

(tangential to disc).(tangential to disc).

Pressure difference at locations before and after the turbine.Pressure difference at locations before and after the turbine.

Shear forces acting on the cylinder due to its rotation.Shear forces acting on the cylinder due to its rotation.


20/34

ResultsResults


21/34

ResultsResults


22/34

ResultsResults


23/34

ResultsResults


24/34

ResultsResults


25/34

ResultsResults


26/34

ResultsResults


27/34

ResultsResults


28/34

ResultsResults


29/34

ResultsResults


30/34

ResultsResults


31/34

ConclusionsConclusions Max. Efficiency = 86 %:Max. Efficiency = 86 %:

DAR = 1DAR = 1 CAR = 2CAR = 2

Number of Cylinders:Number of Cylinders: No Effect on Force.No Effect on Force.

Increases Power Output.Increases Power Output.

Minimum Gap.Minimum Gap.


32/34

ConclusionsConclusions Disc and Cylinder Radii:Disc and Cylinder Radii:

Cylinder Radius increased Force.Cylinder Radius increased Force.Tangential Velocity components.Tangential Velocity components.

System Efficiency depends strongly onSystem Efficiency depends strongly onParameters.Parameters.


33/34

RecommendationsRecommendations1.1. Advanced Optimization Schemes.Advanced Optimization Schemes.

2.2. Include Height:Include Height:


34/34

RecommendationsRecommendations3.3. Staggered Cylinder Arrangement.Staggered Cylinder Arrangement.

4.4. Analyze proposed Turbine coupled with SolarAnalyze proposed Turbine coupled with SolarChimney.Chimney.

5.5. Experimental Validation.Experimental Validation.

latif_mohamed-use of magnus effect rotors as wind turbines for solar chimney power plants

Documents