LOW COST, TINY SIZED MEMS HYDROPHONE SENSOR FOR WATER PIPELINE LEAK DETECTION

Abstract

In this paper, we present an experimental investigation of a water pipeline leak detection system based on a low cost, tiny sized hydrophone sensor fabricated using the micro-electromechanical system (MEMS) technologies. A 10 x 10 element arrayed MEMS hydrophone device with chip size of 3.5 x 3.5 mm2 was used in the experiment. The hydrophone device is packaged with a customized on-board pre-amplification circuit using an acoustic transparent material. The overall package size of the MEMS hydrophone is 1.2 cm x 2.5 cm. The packaged MEMS hydrophone achieves an acoustic sensitivity of -180 dB (re: 1 V/µPa), a bandwidth from 10 Hz to 8 kHz, and a noise resolution of around 60 dB (re: 1 µPa/ √(Hz )) at 1 kHz. A section of ductile iron water pipeline with an internal diameter of 10 cm, wall thickness of 0.73 cm and length of 30 m is constructed as the test bed for the water leak detection. Two different leak sizes with leak flow rates of about 30 L/min and 180 L/min are designed along the pipe, which is pressurized at 3.2 Bar. Analysis of the transient signals and spectrograms shows that the MEMS hydrophone can capture the key acoustic information of the water leak, i.e. identifying the leak and locating the leak position. The measurement results demonstrate the feasibility to construct an affordable, highly efficient, real-time, and permanent in pipe pipeline health monitoring networks based on the MEMS hydrophones due to their high performance, low cost and tiny size.

Existing System

Permanent acoustic sensor networks

Proposed System

In this work, a feasibility study of leak detection is performed by using the micro-electromechanical system (MEMS) hydrophones, which feature compact size, low cost and small power consumption. The reported MEMS hydrophones exhibit great potential applications in the pipeline leak detection networks. This paper presents an experimental investigation of a water pipeline leak detection, for the first time, using a low cost, tiny sized hydrophone sensor based on MEMS technology.

Architecture

BLOCK DIAGRAM