ME 360 – H09
Name _________________________
1) Torque T for a small maritime diesel engine was tested as a function of engine speed x as shown
below. Use MATLAB “polyfit” to determine the best-fit quadratic model for torque as a function of
engine speed. Use “polyval” to provide a plot of the raw data and your quadratic model. Provide
hardcopy of your code.
T = __________ x2 + __________ x + __________
x = engine speed
[1000 rpm]
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
T = engine torque
[N.m]
500
569
636
679
719
724
712
662
606
531
2) Use your results from above to predict maximum engine power and the engine speed at which
it would be produced. Remember that maximum power does not occur at maximum torque.
Provide a plot of data and your torque model.
PMAX = __________
rpm@PMAX = __________
3) Select a suitable diameter for the output shaft of this engine. State all assumptions.
d = _______________