simulation in which was varied sinusoidally with time. For the quasi- 
steady simulation, runs were conducted at five different values of yw, from 
1.85 degrees bow up from the calm water equilibrium VW=V ou) to 1.85 de- 
grees, bow down from vow (Tables 3 and 4). For the unsteady pitch simu- 
lation, the value of ~ was varied sinusoidally about vow with an ampli- 
tude of 1.85 degrees and a frequency of 0.8 hertz.* The selected scaled 
amplitude and frequency were within the predicted response characteristics 
of the DD-963. All runs were conducted in calm water; therefore, the re- 
sponse of the hull to the seaway was simulated but the seaway was not 
simulated. 
Acceleration runs were conducted based on analytical dynamic simu- 
lation studies of the DD-963.-> The experimental conditions followed run 
7501061 of Reference 29, which was an acceleration from 8.7 knots to full 
power (see Tables 3 and 4 and Figure 7). Trim and displacement were fixed 
at the values corresponding to the self-propulsion condition (Condition 1 
of Table 3). Two types of runs were conducted: (1) quasi-steady runs in 
which all quantities including model speed V, rotational speed n, and pro- 
peller pitch P were held constant (V=n=P=0), and (2) unsteady runs in 
which V was varied with time but n and P were held constant (V>0, n=P=0). 
For the quasi-steady simulation, runs were conducted at five different 
combinations of V, n, and P. The conditions for each run represent the 
conditions at one instant of time during a "true'' acceleration in which 
V, n, and P vary with time. Thus, one "true" acceleration run is repre- 
sented by five steady runs which do not simulate the time rate of change 
of V, n, and P. For the unsteady simulation, runs were conducted at the 
same five combinations of fixed n and P as used for the quasi-steady simu- 
lation, and V was varied with time (the same variation was used for each 
run) representing an acceleration of the model hull (Figure 7). For each 
of these runs, data are of interest only near that value of V which oc- 
curred concurrently with the fixed values of n and P during the "true" 
x 
Full scale equivalent frequency is 0.16 hertz. 
Cea C.J. and T.R. Harper, "Propulsion Dynamics Simulation of the 
DD-963 Class Destroyer," Propulsion Dynamics, Inc., Report 74R1B (January 
OID) he 
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