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Andersson, H., Cehlin, M. & Moshfegh, B. (2024). An Investigation Concerning Optimal Design of Confluent Jets Ventilation with Variable Air Volume. The International Journal of Ventilation
Open this publication in new window or tab >>An Investigation Concerning Optimal Design of Confluent Jets Ventilation with Variable Air Volume
2024 (English)In: The International Journal of Ventilation, ISSN 1473-3315, E-ISSN 2044-4044Article in journal (Refereed) Epub ahead of print
Abstract [en]

This  parametric study aims to predict the  performance of confluent jets ventilation (CJV) with variable air  volume (VAV) from four  CJV  design parameters. A  combination of  computational fluid dynamics (CFD), and response surface method (RSM) has  been used to  predict the  energy efficiency, thermal comfort and  IAQ  for  the  four  expected vital  design variables, i.e.,  heat load (XH),  number of  nozzles (XN),  airflow rate  (XQ) and  supply temperature (XTS).  The  RSM was  used to  generate a  quad-ratic  equation for  the  response variables exhaust temperature (TE),  sup-ply  temperature (TP),  PMV, DR, eT and  ACE. The  RSM  shows that  the  TE, TP and PMV were independent of the number of nozzles. The proposed equations were used to  generate setpoints optimized for  thermal com-fort  (PMV) for  summer, spring and  winter cases with different CLO  fac-tors  and  different TS under a  scenario where the  heat load varied between 10-30W/m2.  TE was  used as  setpoint to  regulate the  airflow rate  to  keep the  PMV values close to  zero. The  results show that  by adapting the TS to the CLO factor both thermal comfort and the energy efficiency can  be  improved. Further energy reduction can  be  gained by downregulating the airflow rate to keep the TP at a fixed setpoint when the  heat load is  decreased. This  means that  a  CJV  can  effectively be combined with VAV  to  improve environmental performance with good thermal comfort (-0.5<PMV <0.5,  DR <20%), above average IAQ (ACE = 106%) and  with a  higher heat removal efficiency (eT = 110%) than conventional mixing ventilation

Place, publisher, year, edition, pages
Taylor & Francis, 2024
Keywords
Parametric study; numerical investigations; confluent jet ventilation; ventilation efficiency; indoor air quality; energy efficiency
National Category
Energy Engineering
Research subject
Sustainable Urban Development
Identifiers
urn:nbn:se:hig:diva-43500 (URN)10.1080/14733315.2023.2300231 (DOI)001145948800001 ()2-s2.0-85184734259 (Scopus ID)
Funder
Knowledge Foundation, 20120273
Available from: 2023-12-28 Created: 2023-12-28 Last updated: 2024-02-19Bibliographically approved
Romanov, P., Jahedi, A., Bäckström, A., Moshfegh, B., Kuběna, I. & Calmunger, M. (2024). Differential Microstructure and Properties of Boron Steel Plates Obtained by Water Impinging Jet Quenching Technique. Steel Research International, 95(1), Article ID 2300406.
Open this publication in new window or tab >>Differential Microstructure and Properties of Boron Steel Plates Obtained by Water Impinging Jet Quenching Technique
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2024 (English)In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 95, no 1, article id 2300406Article in journal (Refereed) Published
Abstract [en]

Soil-working tools in agriculture are made of boron-containing steels with high wear resistance and hardenability. Nevertheless, these tools are subject to high impacts, abrasive wear, and fatigue and are therefore prone to failure. To combine varying levels of properties within one component in as-quenched condition can be beneficial for such products. To obtain this property variation, a component must undergo a complex and controllable cooling. Therefore, the aim of this work is to obtain a microstructure gradient along two 15 mm-thick steel plates in a newly developed test rig by water jet impingement technique to confirm its controllability and flexibility. Furthermore, a quenching simulation model is created for hardness prediction using phase transformation data from a machine learning tool. Microstructure variation is observed using light optical microscopy and the electron backscatter diffraction technique. Mechanical properties are studied through tensile tests and hardness measurements and are also compared with simulation results. The 0.27 mass% C steel sample is obtained in almost fully martensitic state transitioning to a softer ferritic/bainitic condition, while the 0.38 mass% C steel sample results predominantly into a fully hardened martensitic state and slightly shows ferritic and bainitic features along the sample. The quenching simulation model shows promising hardness prediction for both steels.

Place, publisher, year, edition, pages
Wiley, 2024
Keywords
boron steel; critical cooling rate; differential quenching; hardenability; martensite
National Category
Civil Engineering
Identifiers
urn:nbn:se:hig:diva-43159 (URN)10.1002/srin.202300406 (DOI)001082647000001 ()2-s2.0-85174217303 (Scopus ID)
Funder
Vinnova, 2017-02281Swedish Agency for Economic and Regional Growth, 20201438
Available from: 2023-10-23 Created: 2023-10-23 Last updated: 2024-01-24Bibliographically approved
Milic, V., Kåge, L., Andersson, M., Enkel, J. & Moshfegh, B. (2023). AI-Assisted Characterization of Cooling Patterns in a Water-Cooled ICT Room. In: 2023 29th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC): . Paper presented at THERMINIC, 27-29 September 2023, Budapest, Hungary. IEEE
Open this publication in new window or tab >>AI-Assisted Characterization of Cooling Patterns in a Water-Cooled ICT Room
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2023 (English)In: 2023 29th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC), IEEE , 2023Conference paper, Published paper (Refereed)
Abstract [en]

The findings of this study demonstrate the potentialities in using the K-means algorithm for grouping data points related to cooling variables of LCP units. Additionally, the results show that it is suitable to divide the data points into four clusters. The identified clusters differ with regards to variables, among other, such as LCP return air temperature and temperature difference between chilled water supply and return. This is beneficial in identifying undesired operational statuses of LCPs, e.g., low temperature difference between chilled water supply and return, which is an indicator of a poor cooling performance. Clusters 1 is characterized by a combination of low LCP return air temperature and low average cooling power, which can be attributed to nonoperational periods during large parts of the analyzed time period. Cluster 2 has moderate LCP return air temperature, relatively low chilled water flow rate, and high △Tchilled water. In contrast, Cluster 3 demonstrates high chilled water flow rate and LCP return air temperatures, with relatively low △Tchilled water. Finally, Cluster 4 is featured by high LCP return air temperature, rather high △Tchilled water, and chilled water flow rate. It should be highlighted that in the context of energy efficiency, it is preferable to have a high △Tchilled water, and a low chilled water flow rate, meaning that Cluster 4 is preferred compared to Cluster 3.

With regards to the use of K-means as method in this research, it enhances data visualization and aids in deeper understanding of complex patterns within a dataset. Consequently, K-means can be used as a tool for data-driven analysis of cooling patterns in ICT rooms. Within the context of this research project, the use of K-means has been key for communication of results to facility management consultants and employees at Ericsson AB. Hence, undesired cooling patterns that deviate from the desired ones can be effectively communicated. Moreover, it is important to address the selection of four clusters, instead of three clusters, which were also considered suitable as previously mentioned. The motivation for this is to obtain a more detailed and comprehensive representation of the cooling characteristics in the dataset. As a result, this allows for a more granular depiction of the cooling patterns in the investigated dataset.

Place, publisher, year, edition, pages
IEEE, 2023
Keywords
ICT Center, AI, Cooling patterns, Water-cooling, K-means clustering
National Category
Energy Engineering
Identifiers
urn:nbn:se:hig:diva-43350 (URN)10.1109/therminic60375.2023.10325892 (DOI)001108606800034 ()2-s2.0-85179623999 (Scopus ID)979-8-3503-1862-3 (ISBN)
Conference
THERMINIC, 27-29 September 2023, Budapest, Hungary
Available from: 2023-11-30 Created: 2023-11-30 Last updated: 2024-01-04Bibliographically approved
Gebeyaw, G. W., Romanov, P., Jahedi, M., Calmunger, M. & Moshfegh, B. (2023). Effect of spatial-temporal behavior of a newly developed cooling system on carbon and stainless steel bar properties. Gävle: Gävle University Press
Open this publication in new window or tab >>Effect of spatial-temporal behavior of a newly developed cooling system on carbon and stainless steel bar properties
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2023 (English)Report (Other academic)
Abstract [en]

This report summaries the work within the project ”Effect of spatial-temporal behavior of a newly developed cooling system on carbon and stainless-steel bar properties”. The project was conducted from 2020-01-01 to 2022-12-31 and was co-produced by SSAB, Outokumpu and University of Gävle (UoG). The Knowledge Foundation, SSAB, Outokumpu and UoG financed the project.

For the Swedish steel companies SSAB and Outokumpu producing special steels, it is very important to be able to control the cooling process in order to produce steel bars with excellent properties. Both steel companies also want to be able to control the cooling process so that the excellent steel properties become even over the bars’ spatial configuration.

The aim of the present project is to reveal the spatial-temporal behavior of a newly developed cooling technology in order to produce steel bars with excellent properties and to control the phase transformation to achieve optimal performance of the steel bars.

By using the special test rig at the UoG, detail temperature measurement mapping, invers solution and direct numerical simulation, the present project has identified and quantified several important aspects related to the quenching process, operating conditions, and temperature field development within the investigated products. The result from the proposed cooling process provides an outstanding cooling rate that is very crucial to obtain the required steel phase and thus the correct properties of the bar with different sizes. Results from this study have also shown that the cost per kg product can be reduced by tunning the process parameters such as soaking time and bar temperature before starting the cooling process.

In addition, both experimental and numerical results of the material investigation show that the cooling technology has resulted in the desired phase transformation and subsequently the desired steel phases and material properties. The results show that the cooling technology and the control of the cooling parameters can be used to optimize the material properties of the bar materials.

These good results and conclusions have been obtained via the deep collaboration between the SSAB, Outokumpu and UoG. The co-production, starting in the steering group planning the work along with the combination of research conducted at UoG and at the companies, have led to a successful project with great knowledge transfer in all direction during the duration of the project.

Place, publisher, year, edition, pages
Gävle: Gävle University Press, 2023. p. 19
Series
Working paper, ISSN 1403-8757 ; 63
Keywords
Thermal management, Advanced cooling, Material characterization, Material modelling
National Category
Materials Engineering
Identifiers
urn:nbn:se:hig:diva-40922 (URN)
Projects
Effect of spatial-temporal behavior of a newly developed cooling system on carbon and stainless steel bar properties
Funder
Knowledge Foundation
Note

Funding: The Knowledge Foundation, SSAB, Outokumpu and University of Gävle

Available from: 2023-02-23 Created: 2023-02-23 Last updated: 2023-02-23Bibliographically approved
Milic, V., Choonya, G., Larsson, U. & Moshfegh, B. (2023). Energieffektiv klimatstyrning i växthus. Gävle: Gävle University Press
Open this publication in new window or tab >>Energieffektiv klimatstyrning i växthus
2023 (Swedish)Report (Refereed)
Abstract [sv]

Den globala efterfrågan på mat förväntas öka avsevärt i framtiden, driven av faktorer såsom befolkningsökning och industriell utveckling. Dessutom har vikten av en robust livsmedelsförsörjning nationellt fått ökad uppmärksamhet med tanke på globala klimatförändringar och politiska konflikter. Matproduktion i klimatstyrda växthus erbjuder lovande möjligheter för att möta den ökande efterfrågan på prisvärda och hållbara livsmedel. Trots de fördelar som är förknippade med matproduktion i växthus, står vi inför ett antal utmaningar som behöver hanteras, särskilt i ett land med kallt klimat som Sverige. Detta inkluderar låga utomhustemperaturer, begränsad solinstrålning, samt höga energikostnader för att upprätthålla ett gynnsamt odlingsklimat. 

I föreliggande studie undersöker vi potential med Wall Confluent Jet (WCJ) för att skapa och upprätthålla en gynnsam inomhusmiljö för grödodling i ett växthusklimat. Fördelarna med WCJ inkluderar bland annat användandet av lågtemperarad industriell spillvärme, utebliven risk för kondens, samt tillförsel av önskvärda nivåer av luftfuktighet och CO2.  Dessutom syftar arbetet till att studera den teknoekonomiska prestandan hos WCJ i jämförelse med konventionell uppvärmning via fjärrvärme. Arbetet är uppdelat i två delar: (1) fältexperiment med mätningar av luft- och yttemperaturer för att studera prestandan i WCJ, och (2) teknoekonomisk analys som inkluderar olika klimatzoner, fjärrvärmepriser, samt olika priser på lågtempererad industriell spillvärme. Ett växthus, med ett integrerar testrum, som är beläget i Hofors används som fallstudie. 

Resultaten visar att WCJ-tekniken levererar en jämn och relativt konstant termisk miljö, samt att WCJ klistras vid både tak- och bakväggens ytor och därmed värmer upp dessa ytor. Vidare, den genomsnittliga energianvändningen för uppvärmning minskar från 381 kWh/m2∙år utan WCJ-teknik till 167 kWh/m2∙år med WCJ (56% minskning). WCJ-tekniken möjliggör också en genomsnittlig minskning av energikostnaderna från 441 kSEK/år till 43 kSEK (>90%).  Detta är kopplat till signifikant lägre energianvändning med WCJ, och betydligt lägre priser för lågtempererad industriell spillvärme jämfört med lokala fjärrvärmepriser för de analyserade klimatzonerna. 

Abstract [en]

The global demand for food is expected to increase significantly in the future, driven by factors such as population growth and industrial development. Additionally, the importance of a robust national food supply has gained increased attention in light of global climate change and political conflicts. Environmentally controlled greenhouse food production offers promising opportunities to meet the growing demand for affordable and sustainable food. However, there are several challenges that need to be addressed, particularly in countries with cold climates like Sweden. These challenges include low outdoor temperatures, limited solar radiation, and high energy costs to maintain desirable greenhouse indoor conditions.

In this study, we explore the potential of the Wall Confluent Jet (WCJ) technology to create and maintain a favorable indoor environment for crop cultivation in a greenhouse setting. The advantages of WCJ include the utilization of low-temperature industrial waste heat, no risk for condensation, and the supply of desired levels of humidity and CO2. Furthermore, the study aims to assess the techno-economic performance of WCJ compared to conventional district heating for heating of greenhouses. The study is divided into two parts: (1) field experiments with measurements of air and surface temperatures to study the performance of the WCJ, and (2) techno-economic analysis considering different climate zones, district heating prices, and variations in prices of low-temperature industrial waste heat. A greenhouse with an integrated lab room located in Hofors is used as a case study.

The results demonstrate that the WCJ technology provides a consistent and relatively stable thermal environment, with WCJ adhering to both the ceiling and back wall surfaces, thereby heating these surfaces. Furthermore, the average energy use for heating decreases from 381 kWh/m2∙year without WCJ technology to 167 kWh/m2∙year with WCJ (a 56% decrease). The WCJ technology also enables an average decrease in energy costs from 441 kSEK/year to 43 kSEK/year (>90%). This is attributed to significantly lower energy use with WCJ and considerably lower prices for low-temperature industrial waste heat compared to local district heating prices in the studied climate zones. 

Place, publisher, year, edition, pages
Gävle: Gävle University Press, 2023. p. 19
Series
Working paper, ISSN 1403-8757 ; 65
Keywords
greenhouse, food production, energy-efficient climate control, WCJ, techno-economic analysis, växthus, matproduktion, energieffektiv klimatstyrning, WCJ, teknoekonomisk analys
National Category
Energy Systems
Identifiers
urn:nbn:se:hig:diva-42924 (URN)
Funder
Swedish Board of Agriculture, 2018-3799
Available from: 2023-08-30 Created: 2023-08-30 Last updated: 2023-08-30Bibliographically approved
Choonya, G., Larsson, U. & Moshfegh, B. (2023). Experimental investigations of flow and thermal behavior of wall confluent jets as a heating device for large-space enclosures. Building and Environment, 236, Article ID 110282.
Open this publication in new window or tab >>Experimental investigations of flow and thermal behavior of wall confluent jets as a heating device for large-space enclosures
2023 (English)In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 236, article id 110282Article in journal (Refereed) Published
Abstract [en]

The study aimed to explore the effects of inlet air temperature, outdoor air temperature, inlet bulk velocity, and the number of nozzles on wall confluent jets (WCJ) propagating along an external cold wall in a large space enclosure such as a greenhouse. A combination of experimental study and Response surface methodology has been used to predict the flow and thermal behavior of the WCJ for the studied cases. Box-Behnken design was used to determine the case matrix for four of the above-mentioned vital variables for non-isothermal cases. The experimental study employed constant current anemometers to measure the velocity and temperature of the WCJ. Results showed that the WCJ attached to the wall under both isothermal and non-isothermal conditions. This flow behavior suggests that the WCJ can be used to heat the external facades of large-space enclosures. All the stated variables were critical to the decay factor and decay rate of maximum velocity, albeit at varying levels. The velocity decayed faster with an increase in the inlet bulk velocity and outdoor air temperature. It also decayed faster as the number of nozzles and inlet air temperature decreased. The external wall surface temperature and the wall-heating effect increased as the momentum of the jet increased. The surface temperature on the external wall was most influenced by the inlet air temperature and least by the number of nozzles. Correlations of the second-order polynomial for the Response surface models that estimate the rate of velocity decay and temperature on the external wall were obtained.

Place, publisher, year, edition, pages
Elsevier, 2023
Keywords
Experimental study; Parametric study; Wall confluent jets; Core zone of the wall confluent jets; Response surface methodology; Large-space enclosure heating
National Category
Energy Systems
Research subject
Sustainable Urban Development
Identifiers
urn:nbn:se:hig:diva-41587 (URN)10.1016/j.buildenv.2023.110282 (DOI)000982766300001 ()2-s2.0-85152428328 (Scopus ID)
Funder
European Regional Development Fund (ERDF)
Available from: 2023-04-13 Created: 2023-04-13 Last updated: 2023-06-01Bibliographically approved
Choonya, G., Larsson, U. & Moshfegh, B. (2023). Heating of Cold Wall with Confluent Jets in Large Space Enclosures: Application in Greenhouse Premises. In: Proceedings of the 5th International Conference on Building Energy and Environment COBEE 2022: . Paper presented at 5th International Conference on Building Energy and Environment, COBEE 2022, Montreal, Canada, 25-29 July 2022 (pp. 1925-1933). Springer
Open this publication in new window or tab >>Heating of Cold Wall with Confluent Jets in Large Space Enclosures: Application in Greenhouse Premises
2023 (English)In: Proceedings of the 5th International Conference on Building Energy and Environment COBEE 2022, Springer , 2023, p. 1925-1933Conference paper, Published paper (Refereed)
Abstract [en]

A parametrical investigation has been carried out to explore the velocity and temperature behaviour of wall confluent jets (WCJ) when used to heat and ventilate a test room, which mimics a greenhouse. This study assessed how the outdoor air temperature and supply air temperature affect the velocity and temperature profiles of the WCJ. The study also evaluated how WCJ can be used to eliminate film-wise condensation on greenhouse enclosure surfaces. Constant current anemometers (CCA) and T-type thermocouples were used to measure air velocity and temperature of the WCJ, air and surface temperature in the cooling chamber and test room. This study found that the supply air temperature affects the magnitude of the WCJ’s temperature in each region but the pattern (shape) of the dimensionless temperature is unaffected. The study also showed that both magnitude and pattern of the dimensionless temperature profiles are unaffected by the outdoor air temperature in all regions of the WCJ. The dimensionless velocity profiles under isothermal and non-isothermal were similar, but the magnitude of the profiles increased as the supply air temperature increased in the merging and impinging regions of the WCJ. WCJ formed a boundary layer of warm fluid on the nearby wall; thus, can be used to reduce condensation on the inner surfaces of the greenhouse enclosure.

Place, publisher, year, edition, pages
Springer, 2023
Series
Environmental Science and Engineering, ISSN 1863-5520
Keywords
Constant current anemometers; Experimental study; Greenhouse heating and ventilation system; Parametric study; Wall confluent jets
National Category
Civil Engineering
Identifiers
urn:nbn:se:hig:diva-43112 (URN)10.1007/978-981-19-9822-5_202 (DOI)2-s2.0-85172729357 (Scopus ID)9789811998218 (ISBN)
Conference
5th International Conference on Building Energy and Environment, COBEE 2022, Montreal, Canada, 25-29 July 2022
Available from: 2023-10-09 Created: 2023-10-09 Last updated: 2023-10-09Bibliographically approved
Romanov, P., Jahedi, M., Petersson, A., Moshfegh, B. & Calmunger, M. (2023). Quenching of Carbon Steel Plates with Water Impinging Jets: Differential Properties and Fractography. In: Procedia Structural Integrity: . Paper presented at 10th International Conference on Materials Structure and Micromechanics of Fracture, Brno, Czech Republic, 10-12 September 2022 (pp. 154-159). Elsevier, 43
Open this publication in new window or tab >>Quenching of Carbon Steel Plates with Water Impinging Jets: Differential Properties and Fractography
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2023 (English)In: Procedia Structural Integrity, Elsevier , 2023, Vol. 43, p. 154-159Conference paper, Published paper (Refereed)
Abstract [en]

The demand for steel components with tailored properties is constantly growing. To obtain a specific variation of microstructuresand mechanical properties along the component it must undergo a controllable cooling. One way to control the cooling rates alongthe component is by using different simultaneous water jet impingements on a hot austenitized surface. This can be done by anewly developed test rig for water Impinging Jet Quenching Technique (IJQT). This work discusses the effect of IJQT onmechanical properties and fracture behavior of 15 mm steel plates containing 0.27 and 0.38 mass-% carbon. The samples werecooled in a specifically designed setup of the technique to obtain simultaneous water and air cooling resulting in diversemicrostructures. The mechanical property gradients of both steels were analyzed through hardness measurements and tensile tests.The fracture surfaces and the near fracture regions were observed using scanning electron microscope and light optical microscoperespectively.The results from tensile tests showed that the larger part of the sample with higher carbon content was fully hardened, howeversmoothly transitioning to a more ductile region. The sample with lower carbon content combined various degrees of hardening andtransitioned from higher to lower ultimate tensile strength values. Fracture behavior of higher carbon steel was predominantlybrittle transitioning to a ductile, while the lower carbon steel had a small region showing brittle fracture transitioning to a largerregion of predominant ductile fracture behavior.

Place, publisher, year, edition, pages
Elsevier, 2023
Series
Procedia Structural Integrity, E-ISSN 2452-3216 ; 43
Keywords
Martensite, Brittle fracture, Ductile fracture, Impinging Jet Quenching, Boron steel
National Category
Energy Engineering
Identifiers
urn:nbn:se:hig:diva-41702 (URN)10.1016/j.prostr.2022.12.251 (DOI)2-s2.0-85159817415 (Scopus ID)
Conference
10th International Conference on Materials Structure and Micromechanics of Fracture, Brno, Czech Republic, 10-12 September 2022
Funder
Vinnova, 2017-02281Swedish Agency for Economic and Regional Growth, 20201438
Available from: 2023-04-29 Created: 2023-04-29 Last updated: 2023-06-07Bibliographically approved
Andersson, H., Cehlin, M. & Moshfegh, B. (2022). A numerical and experimental investigation of a confluent jets ventilation supply device in a conference room. Energies, 15(5), Article ID 1630.
Open this publication in new window or tab >>A numerical and experimental investigation of a confluent jets ventilation supply device in a conference room
2022 (English)In: Energies, E-ISSN 1996-1073, Vol. 15, no 5, article id 1630Article in journal (Refereed) Published
Abstract [en]

In this study, confluent jets ventilation (CJV) supply devices with three different nozzle arrays (1 × 19, 2 × 19, 3 × 19) were investigated both numerically and experimentally at two different airflow and supply air temperature set-ups. The performance of the CJV supply devices was investigated concerning thermal comfort, indoor air quality (IAQ), and heat removal effectiveness in a conference room environment. A comparison between the experimental and numerical results showed that the v2−f model had the best agreement out of the investigated turbulence models. The numerical results showed that the size of the array had a great impact both on near-field development and on the conditions in the occupied zone. A larger array with multiple rows and a lower momentum conserved the inlet temperature and the mean age of the air better than a single-row array with a higher momentum. A larger array with multiple rows had a higher IAQ and a greater heat removal effectiveness in the occupied zone because the larger array conserved the mean age of air better and the buoyancy driven flow was slightly better at removing the heat. Because of the lower inlet velocities, they also had lower velocities at ankle level, which decreased the risk of draft and thermal discomfort.

Place, publisher, year, edition, pages
MDPI, 2022
Keywords
experimental investigations; numerical investigations; confluent jet ventilation; ventilation efficiency; indoor air quality
National Category
Energy Systems
Research subject
Sustainable Urban Development
Identifiers
urn:nbn:se:hig:diva-38004 (URN)10.3390/en15051630 (DOI)000773636000001 ()2-s2.0-85125196328 (Scopus ID)
Funder
Knowledge Foundation, 20120273
Available from: 2022-02-22 Created: 2022-02-22 Last updated: 2023-08-28Bibliographically approved
Eriksson, M., Akander, J. & Moshfegh, B. (2022). Investigating energy use in a city district in nordic climate using energy signature. Energies, 15(5), Article ID 1907.
Open this publication in new window or tab >>Investigating energy use in a city district in nordic climate using energy signature
2022 (English)In: Energies, E-ISSN 1996-1073, Vol. 15, no 5, article id 1907Article in journal (Refereed) Published
Abstract [en]

This paper focuses on multi-family buildings in a Swedish city district, erected between 1965 and 1973, which are now in need of renovation. For the two types of multi-family buildings in the district, tower buildings and low-rise buildings, dynamic energy use is predicted by using an energy signature method. The energy signature is then used to calculate the primary energy use number of the building stock, according to calculations methods dictated by Swedish building regulations. These regulations are also used to assess which multi-family buildings are in need of renovation, based on the buildings’ primary energy use. For buildings that need energy renovations, it is simulated so that the energy use of each multi-family building complies with these same building regulations. The proposed methodology for simulating energy renovation also determines new energy signature parameters, related to building heat loss coefficient, balance temperature and domestic hot water usage. The effects of simulated renovation are displayed in a duration diagram, revealing how a large-scale renovation affects the district’s heat load in different annual periods, which affects the local district heating system. Sensitivity analysis is also performed before and after simulated energy renovation. 

Place, publisher, year, edition, pages
MDPI, 2022
Keywords
Energy signature method; district heating, district energy use; multi-family buildings; building stock; energy renovation
National Category
Energy Systems
Research subject
Sustainable Urban Development
Identifiers
urn:nbn:se:hig:diva-37582 (URN)10.3390/en15051907 (DOI)000768471700001 ()2-s2.0-85128952183 (Scopus ID)
Available from: 2022-01-06 Created: 2022-01-06 Last updated: 2023-08-28Bibliographically approved
Projects
Benefits for the environment, natural resources and economy with a new advanced technology for cooling metals [2017-02281_Vinnova]; University of Gävle
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-3472-4210

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