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<export-example>
  <doc>
    <id>5543</id>
    <completedYear/>
    <publishedYear>2023</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>1</pageFirst>
    <pageLast>12</pageLast>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume>278</volume>
    <type>article</type>
    <publisherName>Elsevier</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>2022-11-03</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Improvements for building-performance simulations by a comparative finite-element method analysis</title>
    <abstract language="eng">This paper presents a method to improve building-performance simulations (BPS) by the comparison and analysis of different approaches based on finite-element method (FEM) models. The lumped parameter method (LPM) is used in several BPS programs and tools. It has the advantage of fast computing times and comparably good accuracy for thermal and energy loads. With the help of detailed FEM simulations, it is possible to further improve the degree of detail and accuracy while maintaining the high simulation speed.&#13;
&#13;
In this work, we compare time-dependent results for local temperatures in a generic reference room within a given periode of time. In a second step, the differences between the models with respect to various physical effects are analyzed and used to introduce additional equations into the LPM model in order to improve its accuracy. Thus, we discuss potentials for improvement for BPS and demonstrate a method of a practical implementation.&#13;
&#13;
The results show minor differences of less than 0.1 K for radiation and heat transfer, so their level of detail in BPS is appropriate. In these terms, no improvements were pursued within the work. However, the FEM simulation is capable of calculating the internal convective heat transfer and thermal bridges more accurately due to the use of computational fluid dynamics (CFD) and the geometrically precise representation of the FEM model. Here, deviations of up to 1 K in room temperature (convective heat transfer) and up to 0.5 K in wall temperatures (thermal bridges) were pointed out.&#13;
&#13;
By improving the LPM with equations obtained from the FEM, these deviations can be reduced to less than 0.2 K, which is a considerable improvement in accuracy.</abstract>
    <parentTitle language="eng">Energy and Buildings</parentTitle>
    <identifier type="doi">10.1016/j.enbuild.2022.112563</identifier>
    <note>Corresponding author: Dragos Paul Schoplocher</note>
    <enrichment key="BegutachtungStatus">peer-reviewed</enrichment>
    <enrichment key="Kostentraeger">EddA (ZIM)</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <enrichment key="CorrespondingAuthor">Dragos Paul Schoplocher</enrichment>
    <licence>Creative Commons - CC BY - Namensnennung 4.0 International</licence>
    <author>Paul Dragos Schloplocher</author>
    <author>Stefan Ettengruber</author>
    <author>Oliver Steffens</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Lumped parameter model</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Finite-element method</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Building performance simulation</value>
    </subject>
    <collection role="ddc" number="620">Ingenieurwissenschaften und zugeordnete Tätigkeiten</collection>
    <collection role="institutes" number="FakANK">Fakultät Angewandte Natur- und Kulturwissenschaften</collection>
    <collection role="othforschungsschwerpunkt" number="16313">Gebäude und Infrastruktur</collection>
    <collection role="oaweg" number="">Hybrid Open Access - OA-Veröffentlichung in einer Subskriptionszeitschrift/-medium</collection>
    <collection role="oaweg" number="">Corresponding author der OTH Regensburg</collection>
    <collection role="institutes" number="">Labor Bauphysik</collection>
  </doc>
  <doc>
    <id>6296</id>
    <completedYear/>
    <publishedYear>2023</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue>1</issue>
    <volume>1</volume>
    <type>article</type>
    <publisherName>ELSP, International Open Science Platform</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Dynamic simulation of isothermal and non-isothermal reduction and oxidation reactions of iron oxide for a hydrogen storage process</title>
    <abstract language="eng">This work aims first to develop a dynamic lumped model for the isothermal reactions of hydrogen/steam with a single iron oxide/iron pellet inside a tubular reactor and to validate the model results against the experimental reaction kinetic data with the help of our STA device. To describe the temporal change in mass, and consequently, the temporal heat of reaction, the shrinking core model, based on the geometrical contracting sphere, is applied. It turned out that, the simulation model can reproduce the experimental, temporal concentration and temperature-dependent conversion rates with a maximum deviation of 4.6% during the oxidation reactions and 3.1% during the reduction reactions. In addition, a measured isothermal storage process comprising one reduction and one oxidation phase with a holding phase in between on a single reacting pellet could be reproduced with a maximum absolute deviation in the conversion rate of 1.5%. Moreover, a lumped, non-isothermal simulation model for a pelletized tubular redox-reactor including 2kg of iron oxide pellets has been established, in which the heat of reaction, heat transfer to the ambient and heat transfer between the solid and gas phases are considered. The temporal courses of the outlet gas concentration as well as the temperatures of the gas stream and the solid material at a constant input gas flow rate and a constant reacting gas inlet concentration but different input gas temperatures are estimated. Because of the endothermic nature of the reduction reaction, the inlet reacting gas temperature shall be kept high to prevent the severe temperature drop in the solid phase and, consequently, the significant reduction of the reaction rate. Contrary to that, the oxidation process requires lower input gas temperatures to avoid the excessive overheating of the reaction mass and, consequently, the sintering of the reacting pellets. Finally, five of the previous reactors have been connected in series to explore the influence of the changing inlet gas temperatures and concentrations on the dynamic performance of each storage mass.</abstract>
    <parentTitle language="eng">Renewable and Sustainable Energy</parentTitle>
    <identifier type="doi">10.55092/rse20230004</identifier>
    <note>Corresponding author: Belal Dawoud</note>
    <enrichment key="CorrespondingAuthor">Belal Dawoud</enrichment>
    <enrichment key="BegutachtungStatus">peer-reviewed</enrichment>
    <licence>Creative Commons - CC BY - Namensnennung 4.0 International</licence>
    <author>Bernd Gamisch</author>
    <author>Stefan Ettengruber</author>
    <author>Matthias Gaderer</author>
    <author>Belal Dawoud</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>hydrogen storage</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>iron/iron oxide</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>redox reactions</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>lumped model</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>isothermal reactions</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>non-isothermal reactions</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>kinetics of reactions</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Aspen Custom Modeler</value>
    </subject>
    <collection role="institutes" number="FAKMB">Fakultät Maschinenbau</collection>
    <collection role="oaweg" number="">Gold Open Access- Erstveröffentlichung in einem/als Open-Access-Medium</collection>
    <collection role="othforschungsschwerpunkt" number="16312">Energie und Mobilität</collection>
    <collection role="institutes" number="">Labor Sorptionsprozesse</collection>
  </doc>
</export-example>
