EV TİPİ BİR FIRININ DÜŞME TESTİNİN SONLU ELEMANLAR YÖNTEMİ İLE MODELLENMESİ

Beyaz eşya sektöründe ürünler genellikle genleştirilmiş polistren malzeme kullanarak ambalajlanmaktadır. Ürün ambalajlanıp tüketiciye ulaşıncaya kadar her an düşme ve darbe etkisinde kalma riskine sahiptir. Olası bir düşme nedeniyle hasar görerek kullanılamaz hale gelecek ürün, satışa hazır bir mamulün satılamaz hale gelmesi anlamına geleceği için kaynak kaybına yol açacaktır. Yüksek sayıda üretim yapan işletmelerde küçük oranda bile bu hasarın görülmesi toplamda ciddi maliyetlere yol açmaktadır. Bu nedenle, ürün fabrikadan çıkmadan önce düşme testine tabi tutulmaktadır. Bu testte fabrikadan çıkmaya hazır bir ürünün kullanılması ve testtin sık sık gerçekleştirilmesi nedeniyle testin masrafı oldukça fazladır. Testin doğal bir kısıtı ise çarpma sırasında ürünün dinamiklerinin ve ürünü oluşturan parçaların hareketlerinin ambalaj malzemesi nedeniyle tam olarak gözlemlenememesidir. Sunulan çalışmada bir fırın sayısal olarak modellenmiş ve farklı düşme senaryoları için davranışı incelenmiştir. Sayısal model gerçekleştirilen deneysel düşme testi sonuçları ile doğrulanmıştır. Böylece tasarım aşamasında düşme sırasında hasara uğrayacak parçaların belirlenmesi ve buna uygun iyileştirmelerin yapılması mümkün olmuştur.

Anahtar Kelimeler:

Düşme Testi, EPS, Sayısal Modelleme, Fırın

Modeling the Drop Test of Household Oven with Finite Element Method

In order to prevent the damages that occur in the course of transportation, polystyrene (EPS) is commonly used in the domestic appliances sector. A product’s falling risk during transportation is not only available on the end user spot but also available at any moment after the packaging stage. It causes loss of resources because, ready to sale product became unsalable after damaged by possible fall. As a result, drop test is performed on products. Due to the fact that the samples of the test are required as ready for end use products and these tests are repeated very often, test expenses are very high. It is also not possible to observe movements of the pieces and product dynamics during the impact completely because of the packaging materials. An oven is modeled numerically and its behavior for various drop scenarios are examined in this study. Numerical model is verified with the experimental drop test results. Thus, it is possible to make improvements in the design by predicting probable damaged parts during impact.

Keywords:

Drop test, EPS, Numerical Analysis, Oven,

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