Kapalı hacim ı̇çerisı̇ndekı̇ bir elektronı̇k kartın hesaplamalı akışkanlar dinamiği, ı̇letim-tabanlı sonlu elemanlar ve deneysel yöntemlerle parametrı̇k olarak termal açıdan ı̇ncelenmesi

Öz

Elektronik elemanlar; otomotiv, havacılık, bilişim, ev eşyaları, sağlık vb. gibi endüstrinin birçok alanında yoğun olarak kullanılmaktadır. Sistemlerin güvenilirliği elektronik ünitelerin güvenilirliğine doğrudan bağlı olduğu için elektronik elemanların ısıl yönetimi zorunludur. Bir elektronik sistemin ısıl davranışını incelemek için bazı yaygın yöntemler mevcuttur. Bunlardan biri, en yaygın ve uygun prosedür izlendiği takdirde en güvenilir yöntem olan deneysel yöntemdir. Diğer bir yöntem ise Hesaplamalı Akışkanlar Dinamiği (HAD) analizidir. Bir diğer sayısal yöntem ise iletim-tabanlı Sonlu Elemanlar Yöntemidir (SEY). Bu çalışmada, üzerinde iki adet ısı yayan komponentin bulunduğu bir elektronik kartın kapalı bir hacim içerisinde doğal taşınım altında zamana bağımlı ısıl davranışı farklı sınır koşulları altında HAD, iletim-tabanlı SEY ve deneysel yöntemler kullanılarak incelenmiştir. Öncelikle iki farklı sınır koşulu için deneyler gerçekleştirilmiştir. Deney sonuçları kullanılarak HAD ve iletim-tabanlı SEY analiz modelleri doğrulanmıştır. Daha sonra, beş farklı senaryo için HAD ve iletim-tabanlı SEY analizleri gerçekleştirilmiştir. HAD analizlerinin sonuçları, elektronik kart ve komponentler üzerinde seçilen noktaların zamana bağımlı sıcaklık değişimi, sıcaklık ve basıncın kontur grafikleri ve farklı anlar için farklı kesitlerde kapalı hacim içindeki havanın hız dağılımı olarak sunulmuştur. Seçilen noktalar için HAD ve iletim-tabanlı SEY analizlerinden elde edilen zamana bağımlı sıcaklık değişimleri karşılaştırılmıştır. Sonuçlar arasındaki farklar yaklaşık 70-100°C sıcaklık mertebesi için %10'dan düşük kalmaktadır.

Anahtar Kelimeler

• Elektronik kartlar
• Hesaplamalı Akışkanlar Dinamiği (HAD)
• iletim-tabanlı Sonlu Elemanlar Yöntemi (SEY)
• termal yönetim
• deney

Parametric thermal investigation of an electronic board in an enclosure by computational fluid dynamics, conduction-based finite element and experimental methods

Öz

Electronic components are used extensively in many fields of industry such as automotive, aerospace, IT, household appliances, health, etc. Since the reliability of systems is directly dependent on the reliability of electronic units, thermal management of electronic components is mandatory. There are some common methods to study the thermal behavior of an electronic system. One of them is the experimental method, which is the most common and the most reliable method if the proper procedure is followed. Another method is Computational Fluid Dynamics (CFD) analysis. Another numerical method is the conduction-based Finite Element Method (FEM). In this study, the time-dependent thermal behavior of an electronic board with two heat-dissipating components in an enclosure under natural convection is investigated using CFD, conduction-based FEA, and experimental methods under different boundary conditions. Firstly, experiments were carried out for two different boundary conditions. CFD and conduction-based FEM analysis models are validated using the experimental results. Afterward, CFD and conduction-based FEM analyses are performed for five different scenarios. The results of CFD analyses are presented as time-dependent temperature variations of selected locations on the electronic board and components, contour plots of temperature and pressure, and velocity distribution of air inside the closed volume at different cross-sections for different moments. The time-dependent temperature variations obtained from CFD and conduction-based FEM analyses are compared for the selected points. The differences between the results are less than 10% for the temperature range of about 70-100°C.

Anahtar Kelimeler

• Electronic cards
• Computational Fluid Dynamics (CFD)
• Conduction-based finite element method (FEM)
• Thermal Management
• Experiment

Kaynakça

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