SIVI NİTROJEN İLE SUNİ DOLU YAPIMI VE ŞİMDİYE KADAR YAPILAN YAPAY DOLULARLA KARŞILAŞTIRILMASI

Öz

Dolu, tanım olarak, donmuş katı bir şekilde yeryüzüne düşen su parçacıklarıdır. Boyutları 20 cm’ye kadar çıkabilmektedir. Bu sert kütleler yeryüzüne 80 ile 110 km/s lik hızlarla çarpmakta, ancak bu çarpışmaya rağmen kırılmamaktadırlar. Doluların bu kütle ve hızlarda verdikleri zarar ise bir hayli fazladır. Örneğin; İspanya’nın Alicante şehrinde 2019’un Ağustos ayında gerçekleşen dolu fırtınası 3 milyon euro değerinde zarar vermiştir. Araba kaportalarına, uçak gövdelerine, evlerin çatılarına, solar panellere, rüzgâr türbinlerine verdikleri zarar her yıl milyonlarca lira kayba neden olmaktadır. Tüm bunlara rağmen dolu ile ilgili çalışmalar, dolunun simüle edilememesi ve dolayısıyla dolunun verdiği hasarın da tam olarak simüle edilememesinden dolayı tam başarıya ulaştığı söylenememektedir. Bu çalışmada daha önceden yapılmamış ve literatüre geçmemiş olan sıvı nitrojen ve su ile suni dolu yapılmaktadır. Daha önceden dolu hasar testlerinde kullanılan çelik toplar, indentörler, normal buz küreleri gibi uygulamaların gerçeğe yakın sonuçlar vermediği ve dolu karakteristiği gösteremediği saptanmıştır. Bu eksiklik, yaptığımız “suni dolunun” gerçekle çok yakın karakterde olduğunun ispatı ile giderilmiştir. İşbu ispat dolunun kırılmaması, atış testlerinde benzer sonuçlar vermesi, suni dolunun yoğunluğu gibi parametrelerin gerçek doluya yakın olması sonucunda pekiştirilmiştir.

Anahtar Kelimeler

• Dolu
• Sıvı nitrojen
• Yapay dolu
• Dolu Darbe Testi

PRODUCTION OF ARTIFICIAL HAILSTONE WITH LIQUID NITROGEN AND COMPARISONS WITH OTHER ARTIFICIAL HAILSTONES UP TO NOW

Öz

Hailstones are, by definition, particles of water that fall into the Earth in a frozen solid. Its dimensions can be up to 20 cm. These hard masses strike the Earth at speeds of 80 to 110 km/h, but they do not break despite this collision. The damage caused by hail at this mass and speed is a great deal. For example, a hailstorm in August 2019 in Alicante, Spain, caused 3 million euros worth of damage. The damage they do to car bodywork, aircraft bodies, roofs of houses, solar panels, and wind turbines causes millions of Turkish liras of losses each year. In spite of all this, the studies related to hail cannot be said to have achieved full success due to the inability to simulate hailstones and therefore the damage caused by hailstones can not be fully simulated. In this study, artificial hailstones are made with liquid nitrogen and water, which have not been done before and have not been passed to the literature. It was determined that applications such as steel balls, indentors, normal ice spheres used in hail damage tests did not produce real results and did not show hail characteristics. This deficiency has been eliminated by the proof that the “artificial hailstones” we have made is very close to reality. This proof is confirmed as a result of not breaking the hailstones, giving similar results in firing tests, and parameters such as the density of the artificial hailstones being close to the actual hailstones.

Anahtar Kelimeler

• Hailstone
• Liquid nitrogen
• Artificial hailstone
• Hailstone Impact Test

Kaynakça

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