HEAT LOSS SENSITIVITY ANALYSIS OF DIFFERENT LINEAR FRESNEL COLLECTOR RECEIVER GEOMETRIES

HEAT LOSS SENSITIVITY ANALYSIS OF DIFFERENT LINEAR FRESNEL COLLECTOR RECEIVER GEOMETRIES Master Thesis Presentation Tareq Yahia Zahw University of Kassel Cairo University Supervised by: Dr. Adel Khalil 18 June 2014

AGENDA Introduction Motivation Thermal Resistance Model Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 2

AGENDA Introduction Motivation Thermal Resistance Model Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 3

Introduction http://www.soltigua.com/prodotti/ftm/working-principle/ Potential for lower manufacturing and installation costs Less land area required for a given amount of produced electricity Lower leakage losses because of the fixed receiver 4

AGENDA Introduction Motivation Thermal Resistance Model Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 5

Motivation http://www.solarmillennium.de/archives/technology/solar_thermal_power_plants/locations/power_plants_located_in_the_earth_s_sun_belt_,lang1,101,192.html 6

Motivation Presence of the secondary receiver Absorbed radiation at the secondary receiver Thermal analysis: Efficiency = Useful Power Output Available Power http://www.buch-der-synergie.de/c_neu_html/c_04_31_sonne_hochtemperatur_parabol.htm Useful Output = Available Power Heat Loss Heat Loss Q = U ΔT +U ΔT + X = U T +U T + X 7

AGENDA Introduction Motivation Thermal Resistance Model Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 8

Thermal Resistance Model 9

Thermal Resistance Model 10

Thermal Resistance Model Glass envelope configuration Glass plate configuration 11

Thermal Resistance Model Non-evacuated glass envelope Evacuated glass envelope Glass plate 12

AGENDA Introduction Motivation Thermal Resistance Model Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 13

Methodology & Results Individual parameter study Global parameter study Parameter categories Variance-based method Sensitivity indices Response surface methodology R value (coefficient of determination) Equation of coded factors Geometry Material Ambient Process 16

Sensitivity Analysis Methodology Individual parameter study Global parameter study Parameter categories Variance-based method Sensitivity indices Response surface methodology R value (coefficient of determination) Equation of coded factors Why variance? Model-independent sensitivity measure. http://popsych.org/2013/07/ Appreciation of interaction effects among input factors. 17

Sensitivity Analysis Methodology Individual parameter study Global parameter study Parameter categories Variance-based method Sensitivity indices Response surface methodology R value (coefficient of determination) Equation of coded factors Main Index (S i ) The contribution of each input parameter to the output Total Index (S Ti ) Sum of both single and interaction effects 18

Ambient Parameters 100 90 80 70 60 50 40 30 20 10 0 Non-evacuated glass envelope Wind velocity Incidence angle DNI Wind direction Ambient temperature Main index Total index 21

Ambient Parameters 22

Ambient Parameters 100 90 80 70 60 50 40 30 20 10 0 Evacuated glass envelope Wind velocity Incidence angle DNI Wind direction Ambient temperature Main index Total index 23

Ambient Parameters 24

Ambient Parameters 100 90 80 70 60 50 40 30 20 10 0 Wind velocity Incidence angle Glass plate DNI Wind direction Ambient temperature Main index Total index 25

Heat Losses (W/m) Ambient Parameters 200 180 160 140 120 100 80 60 40 20 0 0 26 100 200 300 q_solabs (W/m) 400

Methodology & Results Thermal Resistance Model Sensitivity analysis Individual parameter study Global parameter study Variance-based method Sensitivity indices Parameter categories Response surface methodology R-squared value (coefficient of determination) Equation of coded factors 27

Methodology Individual parameter study Global parameter study Parameter categories Variance-based method Sensitivity indices Response surface methodology R 2 value (coefficient of determination) Equation of coded factors 28

Methodology Individual parameter study Global parameter study Parameter categories Variance-based method Sensitivity indices Response surface methodology R value (coefficient of determination) Equation of coded factors 29

Response Surface 2 Q loss = A o + A 1 v w + A 2 v w T abs T ambient + A 3 T abs T ambient + A 4 T abs Non-evacuated glass envelope 30

Response Surface 2 Q loss = A o + A 1 v w + A 2 v w T abs T ambient + A 3 T abs T ambient + A 4 T abs Evacuated glass envelope 31

Response Surface 2 Q loss = A o + A 1 v w + A 2 DNI + A 3 T abs T ambient + A 4 T abs Glass plate 32

AGENDA Introduction Motivation Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 33

Conclusion Glass envelope correlation: Q = A + v (A + A T T ) + A T T + A T R = 99.72% Glass plate correlation: Q = A + A v + A DNI + A T T + A T R = 99.65% Model validation Aperture area of the main mirrors Heat Fluid Temperature Reflectance of the secondary receiver 34

AGENDA Introduction Motivation Methodology & Results Conclusion Future Work http://www.seia.org/policy/solar-technology/concentrating-solar-power 35

Future Work Validating the model with varying the geometry and material parameters Examining the LFC performance versus the proposed model Further studies for the dynamic evaluation of the heat loss 36

Thanks! Tareq Yahia Zahw 37