New-York tribune., 1907-05-27
TEST MODELS OF LINERS
North German Lloyd Determines
Shape of Ships by Experiment.

When the chief engineer Of the North German
Lloyd Steamship Company decided recently that
the company's steamers should not have tur-
bine engines. the line built experiment station
at Rremcrhaven. where models Of paratnne ana
wood are tested daily. With reciprocating engines
of high power and the perfection Of models OF
least resistance. the line hopes to maintain If not
exceed its record for fast trips between New YORK
and Bremen.
The new steamer Kronprinzessin Ceclie. which
will soon make her maiden trip to this port was
evolved from careful experiments with dozens OF
models. and the company expects she Will pteak
all records between New York and plymouth.
The tests of the models made with the utmost
secrecy. and few if any persons other than the
conpany's engineers and captains are permitted
TO visit the experimental basin. Gustav H. Sch"ap.
the New York representative Of the North German
Lloyd Line who when abroad recently devoted
several days observation of the tests discussed
the subject yesterday. He said:
THE requisite power for driving the model at
speed corresponding with the actual rate OF the
finished ship" he said rs measured by a dynamo
meter. and then calculated for the vessel Itself by
a method formulated by W. Froudc. the English
engineer Every steamer has to fuhi certain con
iitions TO speed, cargo, capacity ETC. and the
displacement of the vessel is determined i'm accord
with tie conditions. once the displacement
is settled upon. It must he regarded rs a constant
factor. a circumstance however. which does not
preclude the possibility of endless forms of ship
construction by varying the length, breadth, draft
and the vessels curves and waterlines
TO ascertain what form is really the best, soy
eral plans. similar TO the first, hut differing from
II in detail. are made. Models Of paraffin
cast In the various forms designed. and by means
o. ingcniously constructed machine are cut in
exact accordance with the ships design on the
ccrstruCtOnal drawing. When ready, the models
are lowered into the basin and brought to cor
rect draft line by wooden weights They then
towed successfully with increasing speed through
the water \ carriage which is driven hy a roue
electric motor. rolls the basin rails
erected each side Of the tank I'm making this
part OF the test. The model hangs under this and
on the carriage. which are placed all the neces-
sary apparatus for the measurement OF resistance
and speed Many towing experiments made.
the number depending on the total sum of the re-
sistings of the models That model is chosen
which, offers the smallest resistance at the speed
required. and from this the working drawings Of
the vessel itself are designed. From the total
sistance of the model tnat of the ship itself is
calculated by application cf a formula for tho
frctional resistance of the skin Of the vessel dis
covered after exhaustive experiments and by cal
culatiOn of the and eddy resistance. The
form of the shin having been determined the sereys
best adapted for its propulsion are designed by
further series of calculations and experiments"