Chapter 3, Problem 3.19P

Interpretation Introduction

(a)

Interpretation:

Draw a calibration curve of mass flow rate versus rotameter reading. Use it to estimate the mass flow rate of a water stream with the rotameter reading of 5.3

Concept introduction:

A calibration curve was prepared in order to use a rotameter. A calibration technique was to calibrate the rotameter. The observed results are as follows,

Rotameter Reading	Collection Time (min)	Volume collected (cm3)
2	1	297
2	1	301
4	1	454
4	1	448
6	0.5	300
6	0.5	298
8	0.5	371
8	0.5	377
10	0.5	440
10	0.5	453

So, we can draw the calibration curve using above data.

Interpretation Introduction

(b)

Interpretation:

For a measured flow rate of 610 g/min, calculate the 95% confidence limits on the true flow rate.

Concept introduction:

The mean difference between duplicates ($D_i$) give the estimation of the standard deviation ($S_x$). This can be calculated by using the following equation,

$S_x\approx \frac{\sqrt{\pi }}{2}{D}_i=0.8862D_i$

Furthermore, confidence limits on measured values can be calculated using the mean difference between duplicates.