Stub Yapılı Kuplaj Tabanlı Mikrodalga Sensör ile Motor Yağı Kullanım Ömrü Tespiti

Öz

Bu çalışmada, motor yağı kullanım ömrünün mikrodalga frekans bölgesinde tahribatsız ve yüksek hassasiyetle izlenebilmesi amacıyla kuplaj hattı destekli, stub yapılı kompakt bir sensör tasarlanmış ve deneysel olarak doğrulanmıştır. AD 255C taban malzemesi üzerine inşa edilen 120 ×30 mm² boyutlarındaki sensör, çeyrek dalga empedans uyumlamasına göre optimize edilerek elektromanyetik alanın numune ile etkileşimi artırılmıştır. Tasarımın performansı, 0 km ile 21.100 km aralığındaki motor yağı numuneleri kullanılarak S21 iletim parametresi üzerinden analiz edilmiştir. Deneysel sonuçlar, yağın kullanım kilometresi arttıkça dielektrik sabitindeki değişime bağlı olarak rezonans frekansında kayma sergilediğini kanıtlamıştır. Hava ortamında 5.48 GHz olan rezonans frekansı; kullanılmamış motor yağında 5.20 GHz’e, 15.500 km’de 5.18 GHz’e ve 21.100 km’de 5.12 GHz seviyesine gerilemiştir. Toplamda 360 MHz’lik bir frekans kayması elde edilmiştir. Önerilen S21 tabanlı yaklaşım, literatürdeki yansıma temelli sistemlere kıyasla daha kararlı bir ölçüm altyapısı sunarak, bakım uygulamaları için düşük maliyetli ve yüksek tekrarlanabilirlikli bir çözüm sağlamaktadır.

Anahtar Kelimeler

• Motor yağ
• Mikrodalga sensör
• kuplaj
• stub
• Motor yağ kullanım ömrü.

Destekleyen Kurum

Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK)

Proje Numarası

1919B012415165

Teşekkür

Bu çalışma, Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK) tarafından 2209-A Üniversite Öğrencileri Araştırma Projeleri Destekleme Programı kapsamında, 1919B012415165 proje numarası ile desteklenmiştir. Yazarlar, sağlanan maddi ve akademik destekten dolayı TÜBİTAK’a teşekkür eder.

Detection of Engine Oil Service Life Using a Stub-Structured Coupled-Line-Based Microwave Sensor

Öz

In this study, a coupling line-supported, stub-structured compact microwave sensor was designed and experimentally validated to monitor engine oil service life non-destructively and with high sensitivity in the microwave frequency range. The sensor, fabricated on an AD 255C substrate with dimensions of 120 × 30 mm², was optimized according to quarter-wave impedance matching conditions to enhance the interaction between the electromagnetic field and the oil sample. The sensor performance was evaluated using the S21 transmission parameter for engine oil samples with usage histories ranging from 0 km to 21,100 km. Experimental results demonstrated that the resonance frequency systematically shifted toward lower frequencies as the oil usage increased, due to changes in the dielectric constant. The resonance frequency decreased from 5.48 GHz in air to 5.20 GHz for unused oil and to 5.12 GHz for oil used for 21,100 km, resulting in a total frequency shift of 360 MHz. The proposed S21-based approach offers a more stable, low-cost, and highly repeatable measurement solution compared to reflection-based systems reported in the literature.

Anahtar Kelimeler

• Engine oil
• Microwave sensor
• coupling
• stub
• Engine oil lifetime.

Destekleyen Kurum

Scientific and Technological Research Council of Türkiye (TÜBİTAK)

Proje Numarası

1919B012415165

Teşekkür

This study was supported by the Scientific and Technological Research Council of Turkey (TÜBİTAK) under the 2209-A University Students Research Projects Support Program, with project number 1919B012415165. The authors thank TÜBİTAK for the financial and academic support provided.

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