Browsing by Author "Oztop, Hakan F."

Now showing 1 - 7 of 7

Citation - WoS: 13
Citation - Scopus: 13
Comparison of exergoeconomic analysis of two different perlite expansion furnaces
(PERGAMON-ELSEVIER SCIENCE LTD, 2015) Mert Gurturk; Hakan F. Oztop; Arif Hepbasli; Hepbasli, Arif; Oztop, Hakan F.; Gürtürk, Mert
In this study exergoeconomic analyses of two different perlite expansion furnaces are performed based on the actual operational data. The exergy cost and the cost per unit of exergy of the expanded perlite produced by the Former Perlite Expansion Furnace (FPEF) are determined to be 62.886 US$/h and 648.309 US5/GJ while those produced by the New Perlite Expansion Furnace (NPEF) are obtained to be 106.734 US$/h and 503.463 US5/GJ respectively. Additionally the production costs based on exergy are calculated to be 0.153 US$/kg for the FPEF and 0.102 US$/kg for the NPEF. The production costs based exergy and exergoeconomic factor of the FPEF are found to be 0.153 US$/kg and 45%. Those of the NPEF are obtained to be 0.102 US$/kg and the 67%. A novel method is also proposed for calculating the exergy cost per unit of the fuel. (C) 2014 Elsevier Ltd. All rights reserved.
Citation - WoS: 96
Citation - Scopus: 104
Energetic and exergetic aspects of solar air heating (solar collector) systems
(PERGAMON-ELSEVIER SCIENCE LTD, 2013) Hakan F. Oztop; Fatih Bayrak; Arif Hepbasli; Hepbasli, Arif; Oztop, Hakan F.; Bayrak, Fatih
Solar air heating (solar collector) is a renewable heating technology and provides heat using solar energy. With fuel costs and other factors solar air heaters (SAL-Is) are getting more attention. The energetic and exergetic performance of SAHs is influenced by a number of factors. The present study reviews the previously conducted studies and applications in terms of design performance assessment heat transfer enhancement techniques experimental and numerical works thermal heat storage effectiveness compassion and recent advances. It may be concluded that energy analysis method has been used in a number of studies while exergy analysis method has been applied to the relatively low numbers of systems. Energy efficiencies of solar air collectors reviewed varied from 47% and 89%. It is expected that this comprehensive study will be very beneficial to everyone involved or interested in the energetic and exergetic design simulation analysis test and performance assessment of SAHs. (C) 2012 Elsevier Ltd. All rights reserved.
Citation - WoS: 144
Citation - Scopus: 162
Energy and exergy analyses of porous baffles inserted solar air heaters for building applications
(Elsevier Science SA, 2013) Fatih Bayrak; Hakan Fehmi Oztop; A. Hepbasli; Hepbasli, Arif; Oztop, Hakan F.; Bayrak, Fatih
This study deals with performance assessment of porous baffles inserted solar air heaters (SAHs) using energy and exergy analysis methods. The porous baffles (PBs) with different thicknesses are used as passive element inside heaters. Closed-cell aluminum foams are chosen as porous materials with thicknesses of 6 mm and 10 mm and a total surface area of 50 cm2. They are placed sequentially and staggered manner onto the SAH. The measured parameters are the inlet and outlet temperatures the absorbing plate temperatures the ambient temperature and the solar radiation. These measurements are performed at two various air mass flow rates of 0.016 kg/s and 0.025 kg/s. Using the first and second laws of thermodynamics energy and exergy efficiencies of the SAHs are calculated and presented for different parameters. In the experiments five types of solar air heaters are tested and compared with each other in terms of their efficiencies. The obtained results showed that the highest collector efficiency and air temperature rise are achieved by SAHs with a thickness of 6 mm and an air mass flow rate of 0.025 kg/s whereas the lowest values are obtained for the SAH with non-baffle collectors and an air mass flow rate of 0.016 kg/s. © 2012 Elsevier B.V. All rights reserved. © 2013 Elsevier B.V. All rights reserved.
Citation - Scopus: 3
Energy and exergy analysis of a perlite expansion furnace
(Springer International Publishing, 2014) Mert Gürtürk; Hakan Fehmi Oztop; A. Hepbasli; Hepbaslı, Arif; Oztop, Hakan F.; Gürtürk, Mert
Utilization opportunities of perlite have made the product adaptable to numerous applications in the construction industrial chemical horticultural and petrochemical industries. Applications of the perlite include filler high and low temperature insulation concrete aggregate textured coatings absorbent and carrier etc. Thus perlite seems to be a very important material. In this paper thermodynamics analysis of a perlite expansion furnace was performed. Both energy and exergy relations were derived for the considered system. Some parameters such as losses irreversibility and design etc. were used for determining the energy and exergy efficiencies. Based on the results of the analysis of the system the energy and exergy efficiencies are calculated to be 66 and 26 % respectively. Some recommendations were also made towards increasing the efficiency in the Turkish perlite industry. © 2017 Elsevier B.V. All rights reserved.
Citation - WoS: 25
Citation - Scopus: 26
Energy and exergy assessments of a perlite expansion furnace in a plaster plant
(Pergamon-Elsevier Science Ltd, 2013) Mert Gürtürk; Hakan Fehmi Oztop; A. Hepbasli; Hepbasli, Arif; Oztop, Hakan F.; Gürtürk, Mert
In this study energy and exergy assessments of a perlite expansion furnace in a plaster factory are performed. Chemical properties of the perlite and its application areas are described. Energy and exergy relations according to the First and Second Law of Thermodynamics are derived. Energy and exergy efficiencies losses and exergy destructions are calculated based on the measurements obtained from the system. Evaluations of environmental impact energy management and economic are finally generalized according to the obtained results. Energy and exergy efficiencies of the furnace are determined to be 66% and 26% respectively. Reference temperature effects on exergy efficiency destruction and sustainability index are also presented. The results showed that the furnace has not been well designed in terms of thermal aspects due to high energy and exergy losses and the manufacturer producing the perlite expanded should establish an energy management structure. © 2013 Elsevier Ltd. All rights reserved. © 2013 Elsevier B.V. All rights reserved.
Citation - WoS: 10
Citation - Scopus: 10
Energy management and environmental aspects of a high capacity perlite furnace through exergetic analysis
(Elsevier Ltd, 2014) Mert Gürtürk; Hakan Fehmi Oztop; A. Hepbasli; Hepbasli, Arif; Oztop, Hakan F.; Gürtürk, Mert
Utilization opportunities of perlite have made the product adaptable to numerous applications in the construction industrial chemical horticultural and petrochemical industries. In this paper exergetic assessment of a High Capacity Perlite Furnace (HCPF) used in a perlite expansion process was performed. The furnace is vertical partially insulated and has a high pertlite production capacity. Both energy and exergy relations were derived for the considered the HCPF. Some parameters such as losses irreversibility and design were considered for determining energy and exergy efficiencies. The obtained results were compared with various perlite expansion furnaces in the literature. The energy and exergy efficiency values for the HCPF were calculated to be 69% and 37% respectively. The results were also assessed in terms of energy management for the perlite production economic evaluation of the HCPF and environmental aspects. © 2014 Elsevier Ltd. All rights reserved. © 2014 Elsevier B.V. All rights reserved.
Citation - WoS: 7
Citation - Scopus: 6
Performance assessment of a polyclinic heating and cooling system in a hospital building
(INDERSCIENCE ENTERPRISES LTD, 2016) Evren Karakasli; Hakan F. Oztop; Arif Hepbasli; Karakasli, Evren; Hepbasli, Arif; Oztop, Hakan F.
The performance of a hospital building heated by a natural gas-fired boiler system was assessed by using energy and exergy analysis methods in this study. The analysis was performed from the primary energy production to the envelope of the building. In the evaluation other parameters such as total exergy input rate per area total exergy input rate per volume and exergy flexibility factor were also utilised. It is found that overall energy and exergy efficiencies of the heating and cooling system were 13.4% and 1.35% respectively. It may be concluded that in establishing energy policies the exergy phenomenon should also be included because exergy is considered as a very useful and effective tool for buildings.