Measuring precise flow through the pipe or open channel is main issue now-days. Many manufacturing companies are working on this problem how to measure more accurate flow. Considering this purpose transit time ultrasonic flow-meters seem to be more reliable. There used two types of transit time flow meters 1. Clamp on 2. Inline. The main difference between inline and clamp on flow- meter is inline flow meters are fixed with pipe and independent with pipe materials and clamp on flow meters are attached with the upper surface of the pipe and depends upon pipe materials. Two transducers are attached opposite to each other. Time of flight is the main variable which leads the flow in the pipe.
Kritsnam has made its own design board sensor which measures flow through the pipe. In this sensor detrended fluctuation analysis (DFA) method is applied to minimize noises. This method is based on time series analysis which fixes the number of bands in which data is recorded and the time interval of record of data. F is the function of n and varies with exponential power of alpha where alpha is called Hurst exponent. Our design board data shows Hurst exponent value very close to 1 which means noises from this board are highly correlated and that has been removed with calibration.
In this way, our board takes an optimum number of n equal to 15. This technology helped our board to give more accurate reading better than TDC board and similar to ADC board. Experiment on this board is done by taking some true value of discharges. Variance getting from our board shows 90% correlation with true value like AC board. Results are shown in the plot.