(a) (b) (c) (d) (e) (f) A flow meter based on the measurement of a differential...

 

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(a) (b) (c) (d) (e) (f) A flow meter based on the measurement of a differential pressure (AP) has been calibrated for flow rates (Q) in the usable range from 2 I-min-¹ to 20 I-min-¹ and the calibration curve is expressed as the following algebraic formula: AP = AQ² + BQ + C where constant A = 1.05 Pa-min2-1-2; B = 2.65 Pa-min-1¹ and C = 40 Pa. Calculate the turn down ratio of the flowmeter. Calculate the sensitivity of the flow meter for flow rate 5 1-min-¹. (i) (ii) (iii) (iv) Explain what is understood by time response and/or time constant for an instrument. You can use a temperature measurement as an example. [2 marks] [1 mark] value of [1 mark] Calculate the sensitivity of the flow meter for flow rate 15 I-min-¹. value of [1 mark] Are the sensitivity values the same? Why? Comment on what you observe. [1 mark] The height of a person was measured eight times with the resulting values in centimetres: 169.5; 170.0; 171.0; 172.0; 168.5; 170.5; 171.5; 173.5. Calculate: (i) (ii) (iii) The average value. The average error. The standard deviation. (10) (ii) (iii) [You need to provide the underlying equations for the above quantities, otherwise your numerical answers will be ignored.] In no more than 20 words each, outline the concepts of: (0) Accuracy. (ii) Precision. Repeatability. [You may sketch a graph to make your points.] Explain the principle of pressure measurement using a Bourdon tube gauge sensor. Use sketches as you see appropriate. [3 marks] In the context of pressure measurement in the process environment, explain the following terms: Absolute Gauge pressure. Differential pressure. [1 mark] [1 mark] [1 mark] ure. related to the principles of measurement: [1 mark] [1 mark] [1 mark] [1 mark] [1 mark] [1 mark] Continued over (a) (b) (c) (d) (e) (f) A flow meter based on the measurement of a differential pressure (AP) has been calibrated for flow rates (Q) in the usable range from 2 I-min-¹ to 20 I-min-¹ and the calibration curve is expressed as the following algebraic formula: AP = AQ² + BQ + C where constant A = 1.05 Pa-min2-1-2; B = 2.65 Pa-min-1¹ and C = 40 Pa. Calculate the turn down ratio of the flowmeter. Calculate the sensitivity of the flow meter for flow rate 5 1-min-¹. (i) (ii) (iii) (iv) Explain what is understood by time response and/or time constant for an instrument. You can use a temperature measurement as an example. [2 marks] [1 mark] value of [1 mark] Calculate the sensitivity of the flow meter for flow rate 15 I-min-¹. value of [1 mark] Are the sensitivity values the same? Why? Comment on what you observe. [1 mark] The height of a person was measured eight times with the resulting values in centimetres: 169.5; 170.0; 171.0; 172.0; 168.5; 170.5; 171.5; 173.5. Calculate: (i) (ii) (iii) The average value. The average error. The standard deviation. (10) (ii) (iii) [You need to provide the underlying equations for the above quantities, otherwise your numerical answers will be ignored.] In no more than 20 words each, outline the concepts of: (0) Accuracy. (ii) Precision. Repeatability. [You may sketch a graph to make your points.] Explain the principle of pressure measurement using a Bourdon tube gauge sensor. Use sketches as you see appropriate. [3 marks] In the context of pressure measurement in the process environment, explain the following terms: Absolute Gauge pressure. Differential pressure. [1 mark] [1 mark] [1 mark] ure. related to the principles of measurement: [1 mark] [1 mark] [1 mark] [1 mark] [1 mark] [1 mark] Continued over

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a i The turn down ratio of the flowmeter is the ratio of the maximum flow rate 20 Imin1 to the minimum flow rate 2 Imin1 Therefore the turn down ratio is 10 ii For a flow rate of 5 Imin1 the different... View the full answer