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Publications (7 of 7) Show all publications
Cehlin, M., Karimipanah, T., Larsson, U. & Ameen, A. (2019). Comparing thermal comfort and air quality performance of two active chilled beam systems in an open-plan office. Journal of Building Engineering, 22, 56-65
Open this publication in new window or tab >>Comparing thermal comfort and air quality performance of two active chilled beam systems in an open-plan office
2019 (English)In: Journal of Building Engineering, E-ISSN 2352-7102, Vol. 22, p. 56-65Article in journal (Refereed) Published
Abstract [en]

The traditional air distribution and supply devices in ventilated rooms are not always able to effectively remove excess heat from the space. Therefore, chilled beams, especially the active systems, are used to achieve the desired cooling demand. The focus of this paper was the potential benefit of a newly designed active chilled beam (ACB) system, to improve heat removal effectiveness local thermal condition and indoor air quality in the occupants’ breathing zone. The system based on 1-way flow design (1W-ACB) was installed in an open-plan office and its performance was studied by analysing the temperatures, velocities and tracer gas concentrations in predetermined risky zones. The system was compared against a traditional 4-way flow design (4W-ACB).

The obtained results showed that heat removal effectiveness was slightly higher for the 1W-ACB system compared to the 4W-ACB system. The local thermal condition was very good close to the workstations when using 1W-ACB. The benefits of the new system were also shown in the occupied zone by analysing the mean age of air and air-change effectiveness (ACE) in the breathing level at the workstation locations. The 1W-ACB system provided air with lower mean age (fresher air), and therefore higher ACE, near the breathing zone at the workstations compared to the 4W-ACB. On the other hand, the 4W-ACB system had the advantage of providing high thermal and mean age of air uniformity throughout the room.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Active Chilled Beam, Air Change Effectiveness, Heat Removal Effectiveness
National Category
Energy Engineering
Identifiers
urn:nbn:se:hig:diva-28583 (URN)10.1016/j.jobe.2018.11.013 (DOI)000457639900006 ()2-s2.0-85057839765 (Scopus ID)
Funder
Vinnova, 2013-03772
Available from: 2018-11-22 Created: 2018-11-22 Last updated: 2019-08-09Bibliographically approved
Ameen, A., Choonya, G. & Cehlin, M. (2019). Experimental Evaluation of the Ventilation Effectiveness of Corner Stratum Ventilation in an Office Environment. Buildings, 9(7), Article ID 169.
Open this publication in new window or tab >>Experimental Evaluation of the Ventilation Effectiveness of Corner Stratum Ventilation in an Office Environment
2019 (English)In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 9, no 7, article id 169Article in journal (Refereed) Published
Abstract [en]

An experimental study was conducted in a room resembling an office in a laboratory environment. The study involved investigating the ability of corner-placed stratum ventilation in order to evaluate the ventilation’s effectiveness and local thermal comfort. At fixed positions, the air temperature, air velocity, turbulence intensity, and tracer gas decay measurements were carried out. The results show that corner-placed stratum ventilation behaves very similar to a mixing ventilation system when considering air change effectiveness. The performance of the system was better at lower supply air flow rates for heat removal effectiveness. For the heating cases, the draught rates were all very low, with the maximum measured value of 12%. However, for the cooling cases, the maximum draught rate was 20% and occurred at ankle level in the middle of the room.

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
air change effectiveness; air exchange efficiency; ventilation effectiveness; draught rate; temperature effectiveness
National Category
Energy Systems
Identifiers
urn:nbn:se:hig:diva-30433 (URN)10.3390/buildings9070169 (DOI)000478645000003 ()2-s2.0-85070072942 (Scopus ID)
Available from: 2019-07-15 Created: 2019-07-15 Last updated: 2019-08-23Bibliographically approved
Ameen, A., Cehlin, M., Larsson, U. & Karimipanah, T. (2019). Experimental Investigation of Ventilation Performance of Different Air Distribution Systems in an Office Environment: Heating Mode. Energies, 12(10), Article ID 1835.
Open this publication in new window or tab >>Experimental Investigation of Ventilation Performance of Different Air Distribution Systems in an Office Environment: Heating Mode
2019 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 10, article id 1835Article in journal (Refereed) Published
Abstract [en]

A vital requirement for all-air ventilation systems are their functionality to operate both in cooling and heating mode. This article experimentally investigates two newly designed air distribution systems, corner impinging jet (CIJV) and hybrid displacement ventilation (HDV) in comparison against a mixing type air distribution system. These three different systems are examined and compared to one another to evaluate their performance based on local thermal comfort and ventilation effectiveness when operating in heating mode. The evaluated test room is an office environment with two workstations. One of the office walls, which has three windows, faces a cold climate chamber. The results show that CIJV and HDV perform similar to a mixing ventilation in terms of ventilation effectiveness close to the workstations. As for local thermal comfort evaluation, the results show a small advantage for CIJV in the occupied zone. Comparing C2-CIJV to C2-CMV the average draught rate (DR) in the occupied zone is 0.3% for C2-CIJV and 5.3% for C2-CMV with the highest difference reaching as high as 10% at the height of 1.7 m. The results indicate that these systems can perform as well as mixing ventilation when used in offices that require moderate heating. The results also show that downdraught from the windows greatly impacts on the overall airflow and temperature pattern in the room.

Keywords
Corner impinging jet, mixing ventilation, displacement ventilation, tracer gas, air exchange effectiveness, air change effectiveness, draught rate
National Category
Energy Systems
Identifiers
urn:nbn:se:hig:diva-29582 (URN)10.3390/en12101835 (DOI)000471016700014 ()2-s2.0-85066877057 (Scopus ID)
Note

Funding agency:

- University of Gävle

Available from: 2019-05-21 Created: 2019-05-21 Last updated: 2019-08-23Bibliographically approved
Ameen, A., Cehlin, M., Larsson, U. & Karimipanah, T. (2019). Experimental investigation of ventilation performance of different air distribution systems in an office environment – cooling mode. Energies, 12(7), Article ID 1354.
Open this publication in new window or tab >>Experimental investigation of ventilation performance of different air distribution systems in an office environment – cooling mode
2019 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 7, article id 1354Article in journal (Refereed) Published
Abstract [en]

The performance of a newly designed corner impinging jet air distribution method with an equilateral triangle cross section was evaluated experimentally and compared to that of two more traditional methods (mixing and displacement ventilation). At nine evenly chosen positions with four standard vertical points, air velocity, turbulence intensity, temperature, and tracer gas decay measurements were conducted for all systems. The results show that the new method behaves as a displacement ventilation system, with high air change effectiveness and stratified flow pattern and temperature field. Both local air change effectiveness and air exchange effectiveness of the corner impinging jet showed high quality and promising results, which is a good indicator of ventilation effectiveness. The results also indicate that there is a possibility to slightly lower the airflow rates for the new air distribution system, while still meeting the requirements for thermal comfort and indoor air quality, thereby reducing fan energy usage. The draught rate was also lower for corner impinging jet compared to the other tested air distribution methods. The findings of this research show that the corner impinging jet method can be used for office ventilation.

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
Corner impinging jet, mixing ventilation, displacement ventilation, tracer gas, air exchange effectiveness, air change effectiveness, draught rate
National Category
Energy Engineering
Identifiers
urn:nbn:se:hig:diva-29443 (URN)10.3390/en12071354 (DOI)000465561400171 ()2-s2.0-85065464428 (Scopus ID)
Available from: 2019-04-05 Created: 2019-04-05 Last updated: 2019-08-16Bibliographically approved
Ameen, A. & Cehlin, M. (2019). Reducing energy usage in multi-family housing. In: 2019 9th International Conference on Future Environment and Energy 9–11 January 2019, Osaka, Japan: . Paper presented at 2019 9th International Conference on Future Environment and Energy, 9–11 January 2019, Osaka, Japan. Institute of Physics Publishing (IOPP), 257, Article ID 012030.
Open this publication in new window or tab >>Reducing energy usage in multi-family housing
2019 (English)In: 2019 9th International Conference on Future Environment and Energy 9–11 January 2019, Osaka, Japan, Institute of Physics Publishing (IOPP), 2019, Vol. 257, article id 012030Conference paper, Published paper (Refereed)
Abstract [en]

The energy usage in residential sector have been around 22% of the total energy use in the world and increasing due to the population growth and higher living standards. The energy sources for this are made up primarily of non-renewable energy resources which generates a large amount of global greenhouse gases. A lot of countries have implemented various regulations and rules to reduce the energy usage in buildings and promoting the use of renewable energy technologies. This paper presents a parametric study of a typical multi-family building in its pre-design stage. The climate location used is Sweden (Gothenburg) and Japan (Osaka). The aim of the study is to compare various configurations and to examine how they affect the energy use. The most interesting configurations are the use of heat pump and solar cells. Other configurations that are examined are infiltration levels, pressure coefficients, wind impact, ventilation with heat recovery, ventilation scheduling, building orientation and finally changing U-values in the building material. Results of this study show that the energy saving, by utilizing a heat pump and solar panels, can reduce the total energy use by 34.9% for Gothenburg and 32% for Osaka. The results also show that the difference in total energy use between the two cities reduce substantially (3% difference) when utilizing a heat pump in combination with solar panels.

Place, publisher, year, edition, pages
Institute of Physics Publishing (IOPP), 2019
Series
IOP Conference Series: Earth and Environmental Science, ISSN 1755-1307, E-ISSN 1755-1315 ; 257
Keywords
Building energy simulation, BES, IDA ICE, multi-family, energy renovation, EEM
National Category
Energy Engineering
Identifiers
urn:nbn:se:hig:diva-29391 (URN)10.1088/1755-1315/257/1/012030 (DOI)
Conference
2019 9th International Conference on Future Environment and Energy, 9–11 January 2019, Osaka, Japan
Available from: 2019-03-18 Created: 2019-03-18 Last updated: 2019-08-12Bibliographically approved
Kabanshi, A., Ameen, A., Hayati, A. & Yang, B. (2018). Cooling energy simulation and analysis of an intermittent ventilation strategy under different climates. Energy, 156, 84-94
Open this publication in new window or tab >>Cooling energy simulation and analysis of an intermittent ventilation strategy under different climates
2018 (English)In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 156, p. 84-94Article in journal (Refereed) Published
Abstract [en]

Energy use on heating, ventilation and air conditioning (HVAC) accounts for about 50% of building energy use. To have a sustainable built environment, energy efficient ventilation systems that deliver good indoor environmental quality are needed. This study evaluates the cooling energy saving potential of a newly proposed ventilation system called Intermittent Air Jet Strategy (IAJS) and compares its performance against a mixing ventilation (MV) system in a classroom located in three cities with different climates, Singapore with ‘hot and humid’, Ahvaz with ‘hot and dry’ and Lisbon with “moderate” climate. The results show a significant reduction of cooling energy need and flexibility in control strategies with IAJS as a primary system in hot and humid climates like Singapore. Hot and dry climate with short cool periods like Ahvaz show possible application and considerable energy savings with IAJS as a primary system under optimized variable setpoints, but moderate climates have an increased risk of occupant discomfort likely due to increased draft especially during the cool season.  Thus, IAJS as a secondary system that operates only during cooling season may be conducive for moderate climates like Lisbon. Additionally, the results show that supply fan energy savings can also be realized if well implemented. 

Keywords
Intermittent air jets; IDA-ICE simulation; Energy savings, Convective cooling, Hot and humid climate, Hot and dry climate, Moderate climate
National Category
Energy Engineering
Identifiers
urn:nbn:se:hig:diva-26564 (URN)10.1016/j.energy.2018.05.093 (DOI)000437073600008 ()2-s2.0-85048207413 (Scopus ID)
Available from: 2018-05-14 Created: 2018-05-14 Last updated: 2018-08-15Bibliographically approved
Kabanshi, A., Ameen, A., Yang, B., Wigö, H. & Sandberg, M. (2017). Energy simulation and analysis of an intermittent ventilation system under two climates. In: Krope J., Olabi, A.G., Goričanec D. & Božičnik S. (Ed.), 10th International Conference on Sustainable Energy and Environmental Protection: Energy Efficiency. Paper presented at SEEP 2017, 10th International Conference on Sustainable Energy & Environmental Protection, 27-30 June 2017, Bled, Slovenia (pp. 1-10). Maribor: University of Maribor Press
Open this publication in new window or tab >>Energy simulation and analysis of an intermittent ventilation system under two climates
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2017 (English)In: 10th International Conference on Sustainable Energy and Environmental Protection: Energy Efficiency / [ed] Krope J., Olabi, A.G., Goričanec D. & Božičnik S., Maribor: University of Maribor Press , 2017, p. 1-10Conference paper, Published paper (Refereed)
Abstract [en]

Energy use on heating, ventilation and air conditioning (HVAC) accounts for about 50% of total energy use in buildings.  Energy efficient HVAC systems that do not compromise the indoor environmental quality and at the same time meet the energy reduction directives/policies are necessary and needed. The study herein, evaluates the energy saving potential of a newly proposed ventilation system in spaces with high occupancy density, called Intermittent Air Jet Strategy (IAJS). The aim of the study was to evaluate through simulations the potential energy savings due to IAJS as compared to a mixing ventilation (MV) system in a classroom located in a ‘hot and humid’ climate (Singapore), and in a ‘hot and dry’ climate (Kuwait). The analysis is based on IDA Indoor Climate Energy simulation software. The results herein demonstrate significant reduction of cooling energy use of up 54.5% for Singapore and up to 32.2% for Kuwait with IAJS as compared to MV. Additionally, supply fan energy savings can also be realized if well implemented.

Place, publisher, year, edition, pages
Maribor: University of Maribor Press, 2017
Keywords
Intermittent air jets, Energy simulation; Energy saving, Setpoint extension, Convective cooling
National Category
Energy Systems
Identifiers
urn:nbn:se:hig:diva-24671 (URN)978-961-286-050-9 (ISBN)
Conference
SEEP 2017, 10th International Conference on Sustainable Energy & Environmental Protection, 27-30 June 2017, Bled, Slovenia
Available from: 2017-07-04 Created: 2017-07-04 Last updated: 2019-01-09Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0002-8349-6659

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