Effect of Magnet Spacing on Magnetic Field Linearity in Selected Commercial Rectangular Magnets

Abstract

In density measurements using magnetic levitation and in magnetic sensor applications, the linearity of the magnetic field and magnetic force is important for measurement convenience. In line with this purpose, an analysis was conducted on a sample magnet configuration with dimensions of 3×60×10 mm to show influence of magnet spacing on the magnetic field linearity. Additionally, the most commonly used magnet dimensions in industry were selected, and the analyses were repeated for each set individually. For each configuration, the distance between the magnets varied between 1 mm and 10 mm, and for each distance, the magnetic field distribution along the magnetization direction on the central axis of the magnets was calculated and fitted to a linear function. Linearity in these fitting processes was evaluated using the R² and rmse metrics. The highest value of R² = 0.9999 and lowest value of rmse=0.25 mT was obtained for the magnet spacing of 2 mm.

Keywords

• Bar Magnet
• Magnetic Levitation
• Magnetic field linearity

Mıknatıs Aralığının Manyetik Alan Doğrusallığına Etkisinin Ticari Dikdörtgen Mıknatıslarda İncelenmesi

Abstract

Manyetik levitasyon kullanılarak yapılan yoğunluk ölçümlerinde ve manyetik sensör uygulamalarında, manyetik alanın ve manyetik kuvvetin doğrusallığı ölçüm kolaylığı açısından önemlidir. Bu amaca uygun olarak, manyetik alan doğrusallığı üzerindeki mıknatıslar arası mesafenin etkisini göstermek için 3×60×10 mm boyutlarında örnek bir mıknatıs konfigürasyonu üzerinde bir analiz yapılmıştır. Ek olarak endüstride sıklıkla kullanılan ticari mıknatıs boyutları seçilerek aynı analizler tekrarlanmıştır. Her bir konfigürasyon için, mıknatıslar arasındaki mesafe 1 mm ile 10 mm arasında değiştirilmiş ve her mesafe için, mıknatısların merkez ekseni boyunca manyetizasyon yönündeki manyetik alan dağılımı hesaplanmış ve doğrusal bir fonksiyona uydurulmuştur. Bu uydurma süreçlerindeki doğrusallık, R² ve rmse metrikleri kullanılarak değerlendirilmiştir. R² = 0.9999 en yüksek değeri ve rmse = 0.25 mT en düşük değeri 2 mm’lik mıknatıs aralığı için elde edilmiştir.

Keywords

• Çubuk Mıknatıs
• Manyetik Levitasyon
• Manyetik alan doğrusallığı

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