SİMULASYON VE TEST METODOLOJİLERİNİN YENİ EGZOZ MANIFOLDU EKİPMANI TASARLAMAK İÇİN ENTEGRASYONU

Öz

Bilgisayar destekli simulasyon, motor geliştirme aşamasında egzoz manifoldu tasarımını için kullanılan etkin araçlardandır. Bununla birlikte, egzoz manifoldu tasarım doğrulaması için, zorlu çalışma koşulları altında motor dinamometre odalarında çeşitli testlerin gerçekleştirilmesi gerekir. Test süreleri, ağır ticari araç (HD) egzoz manifoldu için 2500 saate kadardır. Bu nedenle doğrulama testleri pahalı ve zaman alıcıdır. Maliyet düşürme amaçları ve daha verimli dinamometre kullanımı için bu pahalı testlerin yerini almanın alternatif yolları aranmaktadır. Bu amaçla, özel test donanımları tasarlanır ve inşa edilir. Bu çalışmadaki sistem, motorla benzer sıcaklık ve kütlesel debi aralıklarında sıcak gaz sağlayan brülör sistemini içerir. Brülör sisteminin dezavantajı, zamanla değişmeyen koşullarda çalışmasıdır. Bu nedenle, motorun titreşimli akış etkisini tam olarak kopyalamak çok zordur. Star-CCM + ve Modefrontier yazılımlarının birleştirilmesiyle, bilgisayar destekli mühendislik çalışması, motor koşulları ile brülör test hücresinde benzer manifold yüzey sıcaklığı dağılımı elde etmenin fizibilitesini değerlendirmek için gerçekleştirilir. Egzoz bacakları vasıtasıyla kütle debisini düzenleyen doğru vana açı pozisyonlarının belirlenmesi amaçlanır. Bu yenilikçi metodoloji, deney aşamasında deneme yanılma sayısını azaltır.

Anahtar Kelimeler

• HAD
• Isı Transferi
• Egzoz Manifold
• Test

INTEGRATION OF THE SIMULATION AND TEST METHODOLOGIES TO DESIGN NOVEL EXHAUST MANIFOLD RIG

Öz

Computer Aided Engineering is an effective tool utilized to drive an exhaust manifold design by early assessment within the engine program development phase. However, in the end, for exhaust manifold design verification, various tests must be performed in engine dynamometer cells under severe operating conditions. The test running durations are up to 2500 hours for the heavy-duty (HD) exhaust manifold. Therefore, the validation tests are expensive and time-consuming. Alternative ways are sought to replace these expensive tests for cost reduction purposes and more efficient dynamometer cells. Thus, the custom test rig is designed and built. This system contains the burner system supplying hot gas at a similar temperature and mass flow ranges with the engine. The drawback of the burner system is, it runs in steady-state mode, so very challenging to replicate the engine's pulsating flow effect exactly. Therefore, with the coupling of Star-CCM+ and Modefrontier, the CAE study is carried out to assess the feasibility of obtaining similar manifold skin temperature distribution in the burner test cell with engine conditions. It is aimed to determine the correct valve opening positions regulating the mass flow rate through the runners. This innovative methodology reduces the trial-and-error count in the experiment phase.

Anahtar Kelimeler

• CFD
• Heat Transfer
• Exhaust Manifold
• Testing

Kaynakça

1. The authors would like to acknowledge the support and activities of Aydin Ayyildiz and Hakan Gokoglu from Ford Otosan.
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