Resumé

Byggesektoren er ansvarlig for ca. 40 % af verdenens totale primærenergiforbrug og hoveddelen af denne energi bliver brugt til at fastholde tilfredsstillende indeklimaforhold med opvarmning, afkøling og ventilation.

De traditionelle energikilder er derudover uigenkaldeligt ved at formindskes og prisen på energi og brændstof stiger gradvist. Oven i det har udledning af gasser i atmosfæren forårsaget langtidsvarige og skadelige forandringer i det globale klima. Som en reaktion på dette er lande startet med at indføre nye, mere krævende lovgivninger og standarder til fremtidig konstruktion og renovering af bygninger. For eksempel forudsætter de nye energirammer i Danmark en reduktion af primærenergiforbruget ved bygninger på forholdsvis 25 % i 2010, 50 % i 2015 og 75 % i 2020 sammenlignet med tal fra 2006. Byggesektoren må, som en konsekvens heraf, udstyres med de nye teknologier, der muliggør overholdelse af de nye krav vedrørende de nye energirammer.

Konceptet, der præsenteres og udvikles i denne afhandling, fokuserer på energioptimering og potentiallet med det nye produkt, der kan udnytte lagring af høj termisk energi (TES) og termiskstyrede bygningssystemer (TABS). Afhandlingen undersøger potentialet ved at inkorporere mikroindkapslet faseskiftmateriale (PCM) i et betondækelement med hulkerne, for at øge kapaciteten for dynamisk varmelagring i den interne klimaskærm i fleretagesbygninger. Undersøgelsen udforsker ydermere afkølingskapaciteten og præstationsevnen for betondæk med PCM og integreret TABS, og fremhæver begrænsninger og udfordringer ved den nye teknologi.

Det fremlagte værk bruger adskillige metoder til at undersøge den dynamiske ydelsesevne for det nyudviklede produkt. Som følge deraf udvikles forsøgsopstillingerne og metodelæren først, for at bestemme de termiske egenskaber for det nye materiale, så som PCM-beton-kombinationen, og derefter for at undersøge ydelsesevnen for de udviklede dæk i en 1:1 skala.

Forskningen er planlagt som en iterativ proces, hvor den første numeriske undersøgelse af dækket med PCM udføres ved brug af de teoretiskbestemte termiske egenskaber for PCM-betonmaterialet. Årsagen til denne iterative forskning er manglen på forsøgsbestemte termiske egenskaber for dette relativt nye materiale. I det andet trin af denne forskning bestemmes de termiske egenskaber for PCM-betonen gennem forsøg og efterfølgende opdateres de første numeriske modeller med de målte termiske egenskaber for det nye kompositmateriale. Til sidst valideres resultaterne fra den numeriske analyse med fuldskalaforsøg, der udføres i et specialudviklet og modificeret hot box apparat. Fuldskalaforsøgene udføres også for de specialudviklede profileret dæk med reliefer, hvorpå varmeudvekslingsoverfladen forøges i forhold til standard flade dæk. De profilerere dæk undersøges med henblik på mængden af varme, der kan lagres i løbet af en typisk dag-nat cyklus i en kontorbygning med specialdesignede spelteindblæsning.

For og fremmest observeredes det, at antagelserne for de teoretiske termiske egenskaber skilte sig ud fra de forsøgsbestemte termiske egenskaber for PCM-beton. Resultaterne opnået fra de første (teoretiske) og opdaterede (forsøg) numeriske modeller reflekterer som følge deraf en væsentlig uoverensstemmelse i den dynamiske varmelagring og afkølingskapacitet for de udviklede dæk. Den forsøgsbestemte termiske ledningsevne og specifikke varmekapacitet for PCM-beton er væsentlig lavere end dem fra de teoretiske beregninger, hvilket i begge tilfælde resulterer i dårligere varmelagring og afkølingseffektpræstationer end oprindeligt forventet.

Resultaterne fra fuldskalaundersøgelsen af dynamisk varmelagring i dækkene indikerede, at der ikke er nogen betydelig forskel mellem dækkene med udvidet varmeudvekslingsoverflade og ét med en ordinær flad overflade. Derudover blev der ikke observeret nogen betydelig forbedring for dækkene med PCM i forhold til deres referencedæk med almindelig mørtelstøbning. Derimod blev en forbedring i varmelagringen observeret for alle dækstøbninger med specialdesignede tegl på bunden med hensyn til standard betondækelementer. Disse resultater var derimod uventede, da materialeegenskaberne for mørtelen, der blev brugt til at støbe tegl med, blev fastsat til at være ringere end dem for betonmaterialet, der blev brugt til at støbe standarddækkene.
OriginalsprogEngelsk
Udgivelses stedAalborg
ForlagDepartment of Civil Engineering, Aalborg University
Antal sider156
StatusUdgivet - 2012
NavnDCE Thesis
Nummer41
ISSN1901-7294

Fingerprint

Phase change materials
Concretes
Heat storage
Thermodynamic properties
Cooling
Tile
Mortar
Ventilation
Specific heat
Numerical models
Office buildings
Thermal energy
Gas emissions
Energy storage
Numerical analysis
Thermal conductivity
Numerical methods
Materials properties
Experiments
Heat transfer

Emneord

  • Phase Change Material
  • Thermal Analysis
  • Concrete Composite
  • Specific Heat Capacity
  • Thermal Mass Activation
  • Dynamic Heat Storage
  • Latent Heat
  • Heat Transfer Enhancement

Citer dette

Pomianowski, M. Z. (2012). Energy Optimized Configuration of Concrete Element with PCM. Aalborg: Department of Civil Engineering, Aalborg University. DCE Thesis, Nr. 41
Pomianowski, Michal Zbigniew. / Energy Optimized Configuration of Concrete Element with PCM. Aalborg : Department of Civil Engineering, Aalborg University, 2012. 156 s. (DCE Thesis; Nr. 41).
@phdthesis{58c0bb11636648b196768e1c925e286c,
title = "Energy Optimized Configuration of Concrete Element with PCM",
abstract = "The building sector accounts for approximately 40{\%} of the world’s total use of primary energy, and the majority of this energy is used to maintain satisfactory indoor climate conditions by heating, cooling and ventilation.Further on, traditional energy sources are irretrievably decreasing and the price of energy and fuel is gradually increasing. On top of that, the gas emissions to the atmosphere cause long-term and hazardous changes to the global climate. As a response to that, countries started to enforce new, more demanding legislations and standards for the newly constructed and renovated buildings. For example, in Denmark the new energy frames assume a reduction of primary energy use for buildings of respectively 25{\%} in 2010, 50{\%} in 2015 and 75{\%} in 2020 compared to year 2006 figures. As a consequence, the building sector has to be equipped with the new technologies that would enable fulfillment of the new requirements regarding the new energy frames.The concept presented and developed in the thesis focuses on the energy optimization and potential of the new product that could utilize the high thermal energy storage (TES) and thermally activated building system (TABS). The work investigates the potential of combining the microencapsulated phase change material (PCM) in the hollow core concrete deck element in order to increase the dynamic heat storage capacity of the internal envelope of the multi-storey buildings. Moreover, the study investigates the cooling capacity and performance of the concrete deck with PCM and integrated TABS and highlights limitations and challenges of the new technology.The presented work utilizes numerical methods to study the dynamic performance of the new product developed. Consequently, the experimental set-ups and methodologies are developed firstly to determine the thermal properties of the new material, such as combined PCM concrete, and secondly to investigate the performance of the developed decks in 1:1 scale.The research is scheduled in an iterative manner, where the initial numerical study of the deck with PCM is performed with use of the theoretically determined thermal properties of the PCM concrete material. The reason for the iterative research is due to the lack of experimentally determined thermal properties of this relatively new material. In the second step of the research, the thermal properties of the PCM concrete are determined by experimental manner and afterwards, the initial numerical models are updated with the measured thermal properties of the new composite material. Finally, the results from numerical analysis are validated by the full-scale experiments performed in a specially developed and modified hot box apparatus. The full-scale experiments are also conducted for the specially constructed perforated decks in which heat exchange surface increases compared to the standard flat decks. The decks with perforations are examined with regards to the amount of heat that could be stored during the typical day-night cycle of an office building with specially designed ventilation inlet slot diffuser.Firstly, it was observed that the assumptions regarding the theoretical thermal properties stand out from the experimentally determined thermal properties of the PCM concrete. Consequently, the results obtained from the initial (theoretical) and updated (experimental) numerical models reflect significant discrepancy of the dynamic heat storage and cooling capacity of the developed decks. The experimentally determined thermal conductivity and specific heat capacity of PCM concrete are significantly lower than ones from the theoretical calculations, what in both cases result in poorer heat storage and cooling power performances than initially expected.Results from the full-scale investigation of dynamic heat storage capacity of decks indicated that there is no substantial difference between decks with extended heat transfer surface and one with an ordinary flat surface. Moreover, no significant improvement was observed for decks with PCM with regards to their reference deck cast with ordinary mortar. On the other hand, an improvement in the heat storage was observed for all deck casts with specially designed tiles on the bottom with regards to standard concrete deck element. These results, however, were unexpected since the material properties of mortar used to cast tiles were determined to be worse than those of concrete material used to cast standard decks.",
keywords = "Phase Change Material, Thermal Analysis, Concrete Composite, Specific Heat Capacity, Thermal Mass Activation, Dynamic Heat Storage, Latent Heat, Heat Transfer Enhancement, Phase Change Material, Thermal Analysis, Concrete Composite, Specific Heat Capacity, Thermal Mass Activation, Dynamic Heat Storage, Latent Heat, Heat Transfer Enhancement",
author = "Pomianowski, {Michal Zbigniew}",
year = "2012",
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publisher = "Department of Civil Engineering, Aalborg University",
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Pomianowski, MZ 2012, Energy Optimized Configuration of Concrete Element with PCM. DCE Thesis, nr. 41, Department of Civil Engineering, Aalborg University, Aalborg.

Energy Optimized Configuration of Concrete Element with PCM. / Pomianowski, Michal Zbigniew.

Aalborg : Department of Civil Engineering, Aalborg University, 2012. 156 s. (DCE Thesis; Nr. 41).

Publikation: Bog/antologi/afhandling/rapportPh.d.-afhandlingForskning

TY - BOOK

T1 - Energy Optimized Configuration of Concrete Element with PCM

AU - Pomianowski, Michal Zbigniew

PY - 2012

Y1 - 2012

N2 - The building sector accounts for approximately 40% of the world’s total use of primary energy, and the majority of this energy is used to maintain satisfactory indoor climate conditions by heating, cooling and ventilation.Further on, traditional energy sources are irretrievably decreasing and the price of energy and fuel is gradually increasing. On top of that, the gas emissions to the atmosphere cause long-term and hazardous changes to the global climate. As a response to that, countries started to enforce new, more demanding legislations and standards for the newly constructed and renovated buildings. For example, in Denmark the new energy frames assume a reduction of primary energy use for buildings of respectively 25% in 2010, 50% in 2015 and 75% in 2020 compared to year 2006 figures. As a consequence, the building sector has to be equipped with the new technologies that would enable fulfillment of the new requirements regarding the new energy frames.The concept presented and developed in the thesis focuses on the energy optimization and potential of the new product that could utilize the high thermal energy storage (TES) and thermally activated building system (TABS). The work investigates the potential of combining the microencapsulated phase change material (PCM) in the hollow core concrete deck element in order to increase the dynamic heat storage capacity of the internal envelope of the multi-storey buildings. Moreover, the study investigates the cooling capacity and performance of the concrete deck with PCM and integrated TABS and highlights limitations and challenges of the new technology.The presented work utilizes numerical methods to study the dynamic performance of the new product developed. Consequently, the experimental set-ups and methodologies are developed firstly to determine the thermal properties of the new material, such as combined PCM concrete, and secondly to investigate the performance of the developed decks in 1:1 scale.The research is scheduled in an iterative manner, where the initial numerical study of the deck with PCM is performed with use of the theoretically determined thermal properties of the PCM concrete material. The reason for the iterative research is due to the lack of experimentally determined thermal properties of this relatively new material. In the second step of the research, the thermal properties of the PCM concrete are determined by experimental manner and afterwards, the initial numerical models are updated with the measured thermal properties of the new composite material. Finally, the results from numerical analysis are validated by the full-scale experiments performed in a specially developed and modified hot box apparatus. The full-scale experiments are also conducted for the specially constructed perforated decks in which heat exchange surface increases compared to the standard flat decks. The decks with perforations are examined with regards to the amount of heat that could be stored during the typical day-night cycle of an office building with specially designed ventilation inlet slot diffuser.Firstly, it was observed that the assumptions regarding the theoretical thermal properties stand out from the experimentally determined thermal properties of the PCM concrete. Consequently, the results obtained from the initial (theoretical) and updated (experimental) numerical models reflect significant discrepancy of the dynamic heat storage and cooling capacity of the developed decks. The experimentally determined thermal conductivity and specific heat capacity of PCM concrete are significantly lower than ones from the theoretical calculations, what in both cases result in poorer heat storage and cooling power performances than initially expected.Results from the full-scale investigation of dynamic heat storage capacity of decks indicated that there is no substantial difference between decks with extended heat transfer surface and one with an ordinary flat surface. Moreover, no significant improvement was observed for decks with PCM with regards to their reference deck cast with ordinary mortar. On the other hand, an improvement in the heat storage was observed for all deck casts with specially designed tiles on the bottom with regards to standard concrete deck element. These results, however, were unexpected since the material properties of mortar used to cast tiles were determined to be worse than those of concrete material used to cast standard decks.

AB - The building sector accounts for approximately 40% of the world’s total use of primary energy, and the majority of this energy is used to maintain satisfactory indoor climate conditions by heating, cooling and ventilation.Further on, traditional energy sources are irretrievably decreasing and the price of energy and fuel is gradually increasing. On top of that, the gas emissions to the atmosphere cause long-term and hazardous changes to the global climate. As a response to that, countries started to enforce new, more demanding legislations and standards for the newly constructed and renovated buildings. For example, in Denmark the new energy frames assume a reduction of primary energy use for buildings of respectively 25% in 2010, 50% in 2015 and 75% in 2020 compared to year 2006 figures. As a consequence, the building sector has to be equipped with the new technologies that would enable fulfillment of the new requirements regarding the new energy frames.The concept presented and developed in the thesis focuses on the energy optimization and potential of the new product that could utilize the high thermal energy storage (TES) and thermally activated building system (TABS). The work investigates the potential of combining the microencapsulated phase change material (PCM) in the hollow core concrete deck element in order to increase the dynamic heat storage capacity of the internal envelope of the multi-storey buildings. Moreover, the study investigates the cooling capacity and performance of the concrete deck with PCM and integrated TABS and highlights limitations and challenges of the new technology.The presented work utilizes numerical methods to study the dynamic performance of the new product developed. Consequently, the experimental set-ups and methodologies are developed firstly to determine the thermal properties of the new material, such as combined PCM concrete, and secondly to investigate the performance of the developed decks in 1:1 scale.The research is scheduled in an iterative manner, where the initial numerical study of the deck with PCM is performed with use of the theoretically determined thermal properties of the PCM concrete material. The reason for the iterative research is due to the lack of experimentally determined thermal properties of this relatively new material. In the second step of the research, the thermal properties of the PCM concrete are determined by experimental manner and afterwards, the initial numerical models are updated with the measured thermal properties of the new composite material. Finally, the results from numerical analysis are validated by the full-scale experiments performed in a specially developed and modified hot box apparatus. The full-scale experiments are also conducted for the specially constructed perforated decks in which heat exchange surface increases compared to the standard flat decks. The decks with perforations are examined with regards to the amount of heat that could be stored during the typical day-night cycle of an office building with specially designed ventilation inlet slot diffuser.Firstly, it was observed that the assumptions regarding the theoretical thermal properties stand out from the experimentally determined thermal properties of the PCM concrete. Consequently, the results obtained from the initial (theoretical) and updated (experimental) numerical models reflect significant discrepancy of the dynamic heat storage and cooling capacity of the developed decks. The experimentally determined thermal conductivity and specific heat capacity of PCM concrete are significantly lower than ones from the theoretical calculations, what in both cases result in poorer heat storage and cooling power performances than initially expected.Results from the full-scale investigation of dynamic heat storage capacity of decks indicated that there is no substantial difference between decks with extended heat transfer surface and one with an ordinary flat surface. Moreover, no significant improvement was observed for decks with PCM with regards to their reference deck cast with ordinary mortar. On the other hand, an improvement in the heat storage was observed for all deck casts with specially designed tiles on the bottom with regards to standard concrete deck element. These results, however, were unexpected since the material properties of mortar used to cast tiles were determined to be worse than those of concrete material used to cast standard decks.

KW - Phase Change Material

KW - Thermal Analysis

KW - Concrete Composite

KW - Specific Heat Capacity

KW - Thermal Mass Activation

KW - Dynamic Heat Storage

KW - Latent Heat

KW - Heat Transfer Enhancement

KW - Phase Change Material

KW - Thermal Analysis

KW - Concrete Composite

KW - Specific Heat Capacity

KW - Thermal Mass Activation

KW - Dynamic Heat Storage

KW - Latent Heat

KW - Heat Transfer Enhancement

M3 - Ph.D. thesis

BT - Energy Optimized Configuration of Concrete Element with PCM

PB - Department of Civil Engineering, Aalborg University

CY - Aalborg

ER -

Pomianowski MZ. Energy Optimized Configuration of Concrete Element with PCM. Aalborg: Department of Civil Engineering, Aalborg University, 2012. 156 s. (DCE Thesis; Nr. 41).