Yatay Sıcak Su Tanklarında Tank İçerisine Eğik Konumlandırılmış Engel Yerleştirmenin Etkisinin Sayısal Olarak İncelenmesi

Year 2018, Volume: 10 Issue: 3, 40 - 51, 31.12.2018

Doğan Erdemir , Buket Turgut , Necdet Altuntop

https://doi.org/10.29137/umagd.480410

Abstract

Güneş enerjili sıcak su sistemlerinde yatay sıcak su tanklarının kullanımı vakum tüplü güneş kolektörlerinin kullanımının artması ve daha estetik bir görünüm sağlamasından dolayı yaygınlaşmaktadır. Artan kullanımına karşın yatay sıcak su tankları ile alakalı literatürde kısıtlı sayıda çalışma bulunmaktadır. Bu çalışmada, bir yatay mantolu sıcak su tankının ısıl performansını arttırmak için tank içerisine eğik konumlandırılmış engel yerleştirmenin etkisi sayısal olarak araştırılmıştır. Engeller şebeke girişinden m=50, 100 ve 150 mm mesafelerde ve yatayla a=60º, 75º ve 90º açı yapacak şekilde yerleştirilmiştir. Böylece engel eğiminin ve konumunun etkisi sayısal olarak incelenmiştir. Sonuçlar; tank içerisindeki sıcaklık dağılımı, manto çıkış ve kullanım suyu sıcaklıkları, ortalama Yatay sıcak su tankıdepolanan su sıcaklığı, enerji ve ekserji verimleri üzerinden verilmiştir. Çalışmanın sonucunda, engel yerleştirilen her durumun, içerisinde engel olmayan duruma göre daha yüksek ısıl performansa sahip olduğu görülmüştür. Termodinamik açısından en iyi durum a=60º ve m=100 mm olduğu durumda elde edilmiştir. Aynı durumda depolama sıcaklığı 35ºC olup, engelsiz tanka göre yaklaşık 4ºC daha yüksektir. Yine aynı durumda manto çıkış sıcaklığı engelsiz tanka göre daha düşük, şebeke çıkış sıcaklığı ise daha yüksektir. Sonuç olarak; tank içerisinde eğik konumlandırılmış engel yerleştirme, içerisinde engel bulunmayan ve dik engel bulunan duruma göre daha yüksek ısıl performans sağlamıştır.

Keywords

Yatay sıcak su tankı, Güneş enerjili sıcak su sistemi, Duyulur ısıl enerji depolama

Numerical Investigation of the Effect of Placing Sloped Obstacle in the Horizontal Hot Water Tanks

Abstract

The use of horizontal hot water tanks in solar hot water systems is becoming widespread due to the increased use of vacuum tube solar collectors and providing a more aesthetic appearance. Despite the increasing use of it, there are a limited number of studies in the literature regarding horizontal hot water tanks. In this study, the effect of placing sloped obstacle in the tank to increase the thermal performance of a horizontal mantle hot water tank was investigated numerically. The obstacle has been located at a distance of m = 50, 100 and 150 mm from the mains input and at an angle of a = 60º, 75º and 90º. Thus, the effect of the slope angle and position has been investigated numerically. Results have been evaluated based on temperature distribution within the tank, mantle outlet and main outlet temperatures, average temperature of stored water, energy and exergy efficiencies. As a result of the study, every situation where the obstacle is placed in the tank has a higher thermal performance than the ordinary tank. The best condition in terms of thermodynamics is seen in case of a = 60º and m = 100 mm. In the same case, the storage temperature is 35ºC and is approximately 5ºC higher than the ordinary tank. In the same case, the mantle outlet temperature is lower than the ordinary tank and the outlet temperature is higher. As a result; The sloped obstacle placement in the tank provides higher thermal performance than the obstacle in which there is no obstacle and the vertical obstacle.

Keywords

Horizontal hot water tank, Solar domestic hot water system, Sensible thermal energy storage

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