A Water Level Sensor Design Using Finite Difference Solution and Its Coding in Matlab

Abstract

Water level sensors are commonly used in industry. Some of the sensors are of capacitive nature. It is important to predict water level accurately. That’s why a good sensor model is needed. The finite difference (FD) method is a simple and commonly used numerical method to solve differential equations. In literature, to the best of our knowledge, the finite difference method has not been used to design such a capacitive sensor yet. In this study, the FD method is used to solve Laplace equation in two dimensions. The variation of the sensor capacitance is obtained as a function of water level. The calculation method given here can be used as a starting point for designing such and similar sensors.

Keywords

• Water level Sensor design
• Finite Difference Method
• Capactive Sensor

Abstract

Su seviye sensörleri endüstride yaygın olarak kullanılır. Bazı sensörler kapasitif niteliktedir. Su seviyesini doğru tahmin etmek önemlidir. Bu yüzden iyi bir sensör modeline ihtiyaç vardır. Sonlu farklar (SF) yöntemi, diferansiyel denklemleri çözmek için yaygın olarak kullanılan basit bir sayısal yöntemdir. Literatürde, bildiğimiz kadarıyla, sonlu farklar yöntemi henüz bir kapasitif sensör tasarımında kullanılmamıştır. Bu çalışmada, SF yöntemi Laplace denklemini iki boyutta çözmek için kullanılmıştır. Sensör kapasitansındaki değişim su seviyesinin bir fonksiyonu olarak elde edilmiştir. Burada verilen hesaplama yöntemi, bu ve benzeri sensörleri tasarlamak için bir başlangıç noktası olarak kullanılabilir.

Keywords

• Su seviyesi Sensörü tasarımı
• Sonlu Farklar Yöntemi
• Kapasitif sensör

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