A fluid velocity measurement system consists of a pitot tube, a differential pressure trans- mitter, an...

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A fluid velocity measurement system consists of a pitot tube, a differential pressure trans- mitter, an 8-bit analogue-to-digital converter and a microcontroller with display facilities. Table Prob. 6 gives the model equations and parameters for each element in the system. The microcontroller calculates the measured value of velocity assuming a constant density. (a) (b) Estimate the mean and standard deviation of the error probability density function assuming the true value of velocity v is 14.0 m s. Use the procedure of Table 3.1, treating the rectangular distributions as normal with = h/3. Explain briefly what modifications could be made to the system to reduce the quanti- ties calculated in (a). Pitot tube Differential pressure transmitter Analogue-to- digital converter Microcontroller with display Model equations AP = pv i=KAP + a n = Ki + a VM = K3n-51 Mean values p = 1.2 K = 0.064 = 4.0 K = 12.80 = 0.0 n rounded off K3 = 1.430 to nearest integer Half-widths of hp = 0.1 h = 0.04 ha, = 0.5 hk = 0.0 rectangular distribution A fluid velocity measurement system consists of a pitot tube, a differential pressure trans- mitter, an 8-bit analogue-to-digital converter and a microcontroller with display facilities. Table Prob. 6 gives the model equations and parameters for each element in the system. The microcontroller calculates the measured value of velocity assuming a constant density. (a) (b) Estimate the mean and standard deviation of the error probability density function assuming the true value of velocity v is 14.0 m s. Use the procedure of Table 3.1, treating the rectangular distributions as normal with = h/3. Explain briefly what modifications could be made to the system to reduce the quanti- ties calculated in (a). Pitot tube Differential pressure transmitter Analogue-to- digital converter Microcontroller with display Model equations AP = pv i=KAP + a n = Ki + a VM = K3n-51 Mean values p = 1.2 K = 0.064 = 4.0 K = 12.80 = 0.0 n rounded off K3 = 1.430 to nearest integer Half-widths of hp = 0.1 h = 0.04 ha, = 0.5 hk = 0.0 rectangular distribution