E1C01 09/14/2010
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1.29 Develop a test plan that might be used to evaluate the fuel efficiency of a production model
automobile. Explain your reasoning.
1.30 A race engine shop has just completed two engines of the same design. How might you determine
which engine performs better: (a) on a test stand (engine dynamometer) or (b) at the race track?
Describe some measurements that you feel might be useful and how you might use that information.
Discuss possible differences between the two tests and how these might influence the results (e.g.,
you can control room conditions on a test stand but not at a track).
1.31 A large batch of carefully made machine shafts can be manufactured on 1 of 4 lathes by 1 of
12 quality machinists. Set up a test matrix to estimate the tolerances that can be held within a
production batch. Explain your reasoning.
1.32 Suggest an approach(es) to estimate the linearity error and the hysteresis error of a measurement
system.
1.33 Suggest a test matrix to evaluate the wear performance of four different brands of aftermarket
passenger car tires of the same size, load, and speed ratings on a fleet of eight cars of the same make.
If the cars were not of the same make, what would change?
1.34 The relation between the flow rate, Q, through a pipeline of area A and the pressure drop, Dp, across
an orifice-type flow meter inserted in that line (Fig. 1.14) is given by
Q ¼ CA
ffiffiffiffiffiffiffiffi ffi
2Dp
r
s
where r is density and C is a coefficient. For a pipe diameter of 1 m and a flow range of 20
C water
between 2 and 10 m
3 /min and C ¼ 0.75, plot the expected form of the calibration curve for flow rate
versus pressure drop over the flow range. Is the static sensitivity a constant? Incidentally, such an
instrument test is described by ANSI/ASME Test Standard PTC 19.5.
Wall
pressure
tap
Q
Pipe
Orifice
meter
1 m
Δp
pressure drop
Figure 1.14 Orifice flow meter setup used for Problem 1.34.
36 Chapter 1 Basic Concepts of Measurement Methods
15:40:39 Page 36
1.29 Develop a test plan that might be used to evaluate the fuel efficiency of a production model
automobile. Explain your reasoning.
1.30 A race engine shop has just completed two engines of the same design. How might you determine
which engine performs better: (a) on a test stand (engine dynamometer) or (b) at the race track?
Describe some measurements that you feel might be useful and how you might use that information.
Discuss possible differences between the two tests and how these might influence the results (e.g.,
you can control room conditions on a test stand but not at a track).
1.31 A large batch of carefully made machine shafts can be manufactured on 1 of 4 lathes by 1 of
12 quality machinists. Set up a test matrix to estimate the tolerances that can be held within a
production batch. Explain your reasoning.
1.32 Suggest an approach(es) to estimate the linearity error and the hysteresis error of a measurement
system.
1.33 Suggest a test matrix to evaluate the wear performance of four different brands of aftermarket
passenger car tires of the same size, load, and speed ratings on a fleet of eight cars of the same make.
If the cars were not of the same make, what would change?
1.34 The relation between the flow rate, Q, through a pipeline of area A and the pressure drop, Dp, across
an orifice-type flow meter inserted in that line (Fig. 1.14) is given by
Q ¼ CA
ffiffiffiffiffiffiffiffi ffi
2Dp
r
s
where r is density and C is a coefficient. For a pipe diameter of 1 m and a flow range of 20
C water
between 2 and 10 m
3 /min and C ¼ 0.75, plot the expected form of the calibration curve for flow rate
versus pressure drop over the flow range. Is the static sensitivity a constant? Incidentally, such an
instrument test is described by ANSI/ASME Test Standard PTC 19.5.
Wall
pressure
tap
Q
Pipe
Orifice
meter
1 m
Δp
pressure drop
Figure 1.14 Orifice flow meter setup used for Problem 1.34.
36 Chapter 1 Basic Concepts of Measurement Methods