I was running through more experiments with the original design for the Hood this morning. I was adjusting the prismatic and midship coefficients to see what effect they had on speed. Leaving the displacement constant, lowering either coefficient has the effect of increasing the draft. When I reduced the Cp to 0.53, the speed actually fell off. I just tried a "light cruiser" Cp and Cm (a high Cp and a low Cm). That had the effect of lowering the speed.
The sure-fire way to increase speed without increasing power was to increase the waterline length. When I increased the length to 890ft, the speed calculated by my program goes up over 32 knots. The specs for the ship in this case were:
Part of the power curve:
At speed of 20knots power is 25410.8 SHP At speed of 21knots power is 29361.2 SHP At speed of 22knots power is 33665.3 SHP At speed of 23knots power is 39244.9 SHP At speed of 24knots power is 45789.9 SHP At speed of 25knots power is 52893.0 SHP At speed of 26knots power is 60556.0 SHP At speed of 27knots power is 68739.5 SHP At speed of 28knots power is 77479.4 SHP At speed of 29knots power is 86787.5 SHP At speed of 30knots power is 98317.3 SHP At speed of 31knots power is 118491.0 SHP At speed of 32knots power is 141457.0 SHP At speed of 33knots power is 167021.0 SHP actual speed for 144000.0 SHP is 32.0995 knots
No comments:
Post a Comment