Sürdürülebilir Kalkınma Amaçları
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- MakaleAçık Erişim2024Scopus SJRQ1Enhancing the performance of parabolic trough solar collectors: Cost-effective innovative designs for sustainable energy harvesting
Karaağaç, Mehmet Onur; Akıncı, Burak; Ergün, Alper
This study aims to improve the performance and stability of parabolic trough solar collectors (PTSC), especially those with heat storage capacity. Three different receiver tube designs have been meticulously developed to achieve this goal. As a result of the research, the Black surface (BS) -PTSC and PTSC- Paraffin wax (PW) systems achieved 26.5% and 56.8% more thermal energy flow, respectively, compared to the conventional PTSC. In addition, while the average thermal efficiencies of the PTSC, BS-PTSC, and PTSC-PW systems were found to be 11.2%, 14.1%, and 16.9%, respectively, the average exergy efficiencies of the PTSC, BS-PTSC, and PTSC-PW were 1.4%, 1.9%, and 2.3%. Painting the black copper pipe and filling the receiver tube with paraffin wax PCM increased thermal and exergy efficiency. Besides, comparing the temperature differences based on the PTSC system, it was found that BS-PTSC and PTSC-PW systems have 12.3% and 16.4% higher tank temperatures, respectively. The findings of this research have demonstrated the potential of parabolic trough solar collectors equipped with heat storage. It has also increased the sustainability index in terms of sustainability and reduced CO2 emissions into the atmosphere. Furthermore, it has been shown that these simple and inexpensive designs, without significant modifications to the system, can achieve high thermal performance without unnecessary expensive components.
AtıfScopus23WoS20OpenAlex24
İncele - Yüksek Lisans TeziAçık Erişim2022Akkuyu Nükleer Güç Santrali'nin termoekonomik analizi ve atık ısının değerlendirilmesi
Elvin Ağtaş
Günümüzde nüfusun ve teknolojik gelişmelerin hızla artmasıyla enerji ihtiyacımızda artmaktadır. Enerji denilince akla ilk gelen elektrik enerjisidir. Son yıllarda elektrik enerjisi üretimi için Nükleer Güç Santralleri (NGS) önemli bir potansiyeldir. Bu çalışma kapsamında, ülkemizin ilk nükleer santrali olan Akkuyu Nükleer Güç Santrali (ANGS) için termoekonomik analiz gerçekleştirilmiştir. Analiz sonucu, NGS çalışma prensibi gereği çevreye atılan ısının faydalı ısıya dönüştürülmesi ile enerji üretim maliyetinin düşürülmesi aynı zamanda ısıl kirliliğin önlenmesi amaçlanmıştır. Akkuyu Nükleer Güç Santrali'ne eşdeğer ekipman değerleri kullanılarak Engineering Equation Solver (EES) programında termodinamik analiz yapılmıştır. Termodinamiğin ikinci yasasına bağlı, maliyet analizi yöntemleri arasında en fazla kullanılan spesifik ekserji maliyetleme (SPECO) yöntemi kullanılarak maliyet analizi yapılmıştır. Çalışma sonucunda, ANGS'nin enerji ve ekserji verimleri sırasıyla %35 ve %68 olarak bulunmuştur. Tesisten atılan ısının dolaylı olarak tesise tekrar kazandırılmasıyla bölgesel ısıtmada (tesiste bulunan lojmanların, misafirhanelerin, ısınma, sıcak su ihtiyacı), bölgenin coğrafik şartları ve geçim kaynağı göz önünde bulundurularak sera ısıtma, zirai kurutma ve ısıtmada kullanmak mümkündür. Böylelikle, %67.99 oranında atık ısı değerlendirilmiş, üretilen enerjinin birim maliyeti düşürülmüş ve aynı zamanda ısıl kirlilikte aynı oranda azaltılmıştır.
- MakaleYalnız künye2010Scopus SJRQ2Numerical analysis of entropy generation in concentric curved annular ducts
Kucuk, Haydar
The entropy generation has been numerically investigated in concentric curved annular square ducts under constant wall temperature boundary condition. The problem has been assumed to be steady, hydrodynamically and thermally fully developed and incompressible laminar flow with constant physical properties. The solutions of discretized equations for continuity, momentum and energy have been obtained by using an elliptic Fortran Program based on the SIMPLE algorithm. Solutions have been achieved for i) Dean numbers ranging from 3.6 to 207.1, ii) Annulus dimension ratios of 5.5, 3.8, 2.9 and 2.36, and iii) Prandtl number of 0.7. In this regard, local entropy generation as well as overall entropy generation in the whole flow field has been analyzed in detail. Moreover, the effects of Dean number and annulus dimension ratio on entropy generation arising from the friction and heat transfer have been investigated. Accordingly, it is concluded that the effect of volumetric entropy generation that is a result of fluid frictional irreversibility can be neglected as compared with volumetric entropy generation due to heat transfer irreversibility. As Dean number increases, the distribution of volumetric entropy generation coming out from the heat transfer irreversibility is formed by the temperature field, which is depending on the curvature.
AtıfScopus19WoS17OpenAlex21İncele - MakaleYalnız künye2010Scopus SJRQ1Exergetic performance analysis of a recirculating aquaculture system
Kucuk, Haydar; Midilli, Adnan; Özdemir, Atilla; Çakmak, Eyüp; Dincer, Ibrahim
This paper examines exergetic aspects of a Recirculation Aquaculture System (RAS) for Black Sea trout (Salmo trutta labrax) fingerling rearing at the Trabzon Central Fisheries Research Institute, Turkey. In its thermodynamic analysis, each component of the RAS is treated as a steady-state steady flow system and its exergetic efficiencies are studied. In addition, the following parameters are measured and recorded in experiments: the mass flow rates, inlet and outlet temperatures and of the system components, surrounding temperatures, and electrical work utilized by the components in the RAS. Based on these experimental data, inlet and outlet exergy values, exergy losses, and exergetic efficiencies of each component in the system are determined to assess their performance. Moreover, the overall system exergy efficiency is determined. The results show that exergy efficiencies of the system components are highly affected by varying input exergy flows as a function of the surrounding temperature and chiller's operating period.
AtıfScopus16WoS13OpenAlex26İncele