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Gasketed plate heat exchangers (PHEs) occupy a crucial position in the energy sector due to their efficient and compact design. A number of studies have focused on making the plate heat exchangers more efficient and compact, since energy usage increases day by day. Therefore, the idea of utilizing nanofluids, whose thermophysical properties are better than those of industrial fluids, have drawn the attention of researchers. An experimental setup was designed and constructed at the TOBB ETU Heat Exchangers Laboratory to investigate the effect of utilizing nanofluids in a plate heat exchanger. The experiments were performed with three different working fluids, namely, tap water and 1 and 0.5 wt.% Al2O3/water nanofluids in a hot cycle. For all cases, the flow rates were 100–450 L/h, and the experiments were repeated three times for accuracy. As a result of this study, new correlations for the Nusselt number and heat transfer enhancement rates were obtained. Moreover, the friction factor correlations were found for all cases, and the effect of nanofluids on the pressure drop has been revealed. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.

Nowadays, with the development of technology, energy demand is increasing and using the energy more efficiently becomes important. Plate heat exchangers are widely used in many applications such as power plants, nuclear reactors, food, chemical industries and air conditioning systems. Because of wide application area, it is very important that plate heat exchangers must be very efficient and compact. In order to make them more efficient and compact, researchers pay attention to utilize nanofluids as a working fluid in plate heat exchangers, since their thermo physical properties are much better than the industrial fluids. Therefore, an experimental set-up is designed and constructed in TOBB ETU, Heat Exchangers Laboratory to test and investigate the effect of utilizing Al2O3/water nanofluids in plate heat exchangers. Experiments are performed with tap water at first, then they are repeated for two different Al2O3/water nanofluid concentrations (1% wt. and 0.5% wt.). For all experiments, flow rates are changing between 100-450 l/h. As a result of this study, correlation of Nusselt number and friction factor for all cases are developed and enhancement rates on heat transfer coefficient are obtained. Moreover, increase on pressure drop due to utilizing Al2O3/water nanofluids is investigated., Günümüzde teknolojinin gelişmesi ile birlikte enerji ihtiyacı giderek artmakta olup, enerjinin daha verimli bir şekilde kullanılması oldukça önemli hale gelmektedir. Isı değiştirgeçleri birçok alanda enerjinin aktarımında kullanılan temel cihazlardır ve sıcak ile soğuk akışkanlar arasında ısı transferini sağlarlar. Diğer ısı değiştirgeçlerinden daha kompakt bir tasarıma sahip olan plakalı ısı değiştirgeçlerinin daha verimli ve olduğundan daha kompakt hale getirmek için bir çok çalışma yapılmıştır. Bu çalışma alanlarından birisi de akışkan olarak ısıl iletkenliği daha iyi olan nanoakışkanların plakalı ısı değiştirgeçleri içerisinde kullanılmasının etkilerini incelemektir. Bu doğrultuda, plakalı bir ısı değiştirgeci içerisinde Al2O3/su nanoakışkanının termal ve hidrolik etkilerini incelemek adına TOBB ETÜ Isı Değiştigeçleri Laboratuvarında bir deney düzeneği kurulmuştur. Deneyler önce su ile gerçekleştirilmiş, ardından sıcak devrede kütlece %1'lik ve %0.5 olmak üzere iki farklı konsantrasyonda Al2O3/su nanoakışkanı için deneyler tekrarlanmıştır. Deneylerde debiler 100 – 450 l/sa arasında değişmektedir. Yapılan çalışmalar sonucunda her durum için Nusselt sayısı ve sürtünme katsayısı korelasyonları oluşturulmuş, ısı transferi katsayısındaki elde edilen iyileştirme oranları belirlenmiştir. Ayrıca basınç düşümündeki gözlenen artış incelenmiştir.

Gasketed plate heat exchangers (PHEs) occupy a crucial position in the energy sector due to their efficient and compact design. A number of studies have focused on making the plate heat exchangers more efficient and compact, since energy usage increases day by day. Therefore, the idea of utilizing nanofluids, whose thermophysical properties are better than those of industrial fluids, have drawn the attention of researchers. An experimental setup was designed and constructed at the TOBB ETU Heat Exchangers Laboratory to investigate the effect of utilizing nanofluids in a plate heat exchanger. The experiments were performed with three different working fluids, namely, tap water and 1 and 0.5 wt.% Al2O3/water nanofluids in a hot cycle. For all cases, the flow rates were 100–450 L/h, and the experiments were repeated three times for accuracy. As a result of this study, new correlations for the Nusselt number and heat transfer enhancement rates were obtained. Moreover, the friction factor correlations were found for all cases, and the effect of nanofluids on the pressure drop has been revealed. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.