A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete

Cheng R., Michal Zbigniew Pomianowski, Per Heiselberg, X. Wang, Y. Zang

Research output: Contribution to conference without publisher/journalPaper without publisher/journalResearch

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Abstract

Integration of phase change materials in building envelopes is a technology that with high potential to decrease the building energy consumption and improve indoor thermal comfort. Accurate measurement of thermal physical properties of PCM-concretes is very important for simulation and evaluation of its energy saving performance. However, there isn’t an effective way to measure thermal physical properties of PCM-concretes accurately. The shortcomings of using traditional testing methods to measure thermal physical properties of PCM-concretes were firstly analyzed. Then a new method based on the inverse problem was proposed to deal with the measurements of thermal conductivity and specific heat of PCM-concretes during the phase change process. This method transforms the determination process to an optimization problem, which regarded the difference between the measured and calculated heat flux and temperature as the objective function, and the thermal conductivity and specific heat distribution with temperature will be automatically adjusted through the Sequential Quadratic Programming (SQP) algorithm. The equivalent specific heat of 4 wt% and 6 wt% PCM concretes were determined using the proposed methods. The accuracy (the maximum error is less than 2%) is acceptable for engineering use. The influences of temperature segments and optimization algorithms were analyzed. The results showed that, SQP method is with the highest accuracy and least complexity compared with the Particle Swarm Optimization and Genetic Optimization methods. Finally, some suggestions to apply this method to other similar problems were proposed to extend its application scope.
Original languageEnglish
Publication date2012
Number of pages10
Publication statusPublished - 2012
EventThe 4th International Conference on Applied Energy - Suzhou, China
Duration: 5 Jul 20128 Jul 2012
Conference number: 4

Conference

ConferenceThe 4th International Conference on Applied Energy
Number4
CountryChina
CitySuzhou
Period05/07/201208/07/2012

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Pulse code modulation
Thermodynamic properties
Concretes
Specific heat
Physical properties
Quadratic programming
Thermal conductivity
Phase change materials
Thermal comfort
Inverse problems
Temperature
Particle swarm optimization (PSO)
Heat flux
Energy conservation
Energy utilization
Testing
Hot Temperature

Keywords

  • Phase change material
  • Thermal physical properties
  • Inverse problem

Cite this

R., C., Pomianowski, M. Z., Heiselberg, P., Wang, X., & Zang, Y. (2012). A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete. Paper presented at The 4th International Conference on Applied Energy, Suzhou, China.
R., Cheng ; Pomianowski, Michal Zbigniew ; Heiselberg, Per ; Wang, X. ; Zang, Y. / A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete. Paper presented at The 4th International Conference on Applied Energy, Suzhou, China.10 p.
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abstract = "Integration of phase change materials in building envelopes is a technology that with high potential to decrease the building energy consumption and improve indoor thermal comfort. Accurate measurement of thermal physical properties of PCM-concretes is very important for simulation and evaluation of its energy saving performance. However, there isn’t an effective way to measure thermal physical properties of PCM-concretes accurately. The shortcomings of using traditional testing methods to measure thermal physical properties of PCM-concretes were firstly analyzed. Then a new method based on the inverse problem was proposed to deal with the measurements of thermal conductivity and specific heat of PCM-concretes during the phase change process. This method transforms the determination process to an optimization problem, which regarded the difference between the measured and calculated heat flux and temperature as the objective function, and the thermal conductivity and specific heat distribution with temperature will be automatically adjusted through the Sequential Quadratic Programming (SQP) algorithm. The equivalent specific heat of 4 wt{\%} and 6 wt{\%} PCM concretes were determined using the proposed methods. The accuracy (the maximum error is less than 2{\%}) is acceptable for engineering use. The influences of temperature segments and optimization algorithms were analyzed. The results showed that, SQP method is with the highest accuracy and least complexity compared with the Particle Swarm Optimization and Genetic Optimization methods. Finally, some suggestions to apply this method to other similar problems were proposed to extend its application scope.",
keywords = "Phase change material, Thermal physical properties, Inverse problem, Phase change material, Thermal physical properties, Inverse problem",
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note = "The 4th International Conference on Applied Energy, ICAE2012 ; Conference date: 05-07-2012 Through 08-07-2012",

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R., C, Pomianowski, MZ, Heiselberg, P, Wang, X & Zang, Y 2012, 'A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete', Paper presented at The 4th International Conference on Applied Energy, Suzhou, China, 05/07/2012 - 08/07/2012.

A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete. / R., Cheng; Pomianowski, Michal Zbigniew; Heiselberg, Per; Wang, X.; Zang, Y.

2012. Paper presented at The 4th International Conference on Applied Energy, Suzhou, China.

Research output: Contribution to conference without publisher/journalPaper without publisher/journalResearch

TY - CONF

T1 - A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete

AU - R., Cheng

AU - Pomianowski, Michal Zbigniew

AU - Heiselberg, Per

AU - Wang, X.

AU - Zang, Y.

PY - 2012

Y1 - 2012

N2 - Integration of phase change materials in building envelopes is a technology that with high potential to decrease the building energy consumption and improve indoor thermal comfort. Accurate measurement of thermal physical properties of PCM-concretes is very important for simulation and evaluation of its energy saving performance. However, there isn’t an effective way to measure thermal physical properties of PCM-concretes accurately. The shortcomings of using traditional testing methods to measure thermal physical properties of PCM-concretes were firstly analyzed. Then a new method based on the inverse problem was proposed to deal with the measurements of thermal conductivity and specific heat of PCM-concretes during the phase change process. This method transforms the determination process to an optimization problem, which regarded the difference between the measured and calculated heat flux and temperature as the objective function, and the thermal conductivity and specific heat distribution with temperature will be automatically adjusted through the Sequential Quadratic Programming (SQP) algorithm. The equivalent specific heat of 4 wt% and 6 wt% PCM concretes were determined using the proposed methods. The accuracy (the maximum error is less than 2%) is acceptable for engineering use. The influences of temperature segments and optimization algorithms were analyzed. The results showed that, SQP method is with the highest accuracy and least complexity compared with the Particle Swarm Optimization and Genetic Optimization methods. Finally, some suggestions to apply this method to other similar problems were proposed to extend its application scope.

AB - Integration of phase change materials in building envelopes is a technology that with high potential to decrease the building energy consumption and improve indoor thermal comfort. Accurate measurement of thermal physical properties of PCM-concretes is very important for simulation and evaluation of its energy saving performance. However, there isn’t an effective way to measure thermal physical properties of PCM-concretes accurately. The shortcomings of using traditional testing methods to measure thermal physical properties of PCM-concretes were firstly analyzed. Then a new method based on the inverse problem was proposed to deal with the measurements of thermal conductivity and specific heat of PCM-concretes during the phase change process. This method transforms the determination process to an optimization problem, which regarded the difference between the measured and calculated heat flux and temperature as the objective function, and the thermal conductivity and specific heat distribution with temperature will be automatically adjusted through the Sequential Quadratic Programming (SQP) algorithm. The equivalent specific heat of 4 wt% and 6 wt% PCM concretes were determined using the proposed methods. The accuracy (the maximum error is less than 2%) is acceptable for engineering use. The influences of temperature segments and optimization algorithms were analyzed. The results showed that, SQP method is with the highest accuracy and least complexity compared with the Particle Swarm Optimization and Genetic Optimization methods. Finally, some suggestions to apply this method to other similar problems were proposed to extend its application scope.

KW - Phase change material

KW - Thermal physical properties

KW - Inverse problem

KW - Phase change material

KW - Thermal physical properties

KW - Inverse problem

M3 - Paper without publisher/journal

ER -

R. C, Pomianowski MZ, Heiselberg P, Wang X, Zang Y. A New Method to Determine Thermal Properties of the Mixture of PCM and Concrete. 2012. Paper presented at The 4th International Conference on Applied Energy, Suzhou, China.