The ROWING Data File

© 2001 Atkinsopht (03/24/02)

The Data File

In order to model a crew, oars, and boat with ROWING many items of fairly accurate data must be made available. Shown below is the skeleton data form used by the program ROWING:

 Job ID-1
 Job ID-2
 Job ID-3
X---+----1----+----2----+----3-2/
10010101          0         1101/ Program Control line; ROWING Ver. 9.00
- Program Control: 1= 0-Blade as drag body      1-Blade as hydrofoil
-                  2= 0-Fixed resistance factor 1-ITTC-'57 skin friction line
-                  3= 0-Linear oarhandle pull   1-Parabolic oarhandle pull
-                  4= 0-Linear L2,4,R8,S8 vels. 1-Parabolic L2,4,R8,S8 vels.
-                  5= 0-No display vectors      1-Display vectors
-                  6= 0,2-Free period fixed     1,3-Stroke rating fixed
-                     0 Power bal. by Period      1 Power bal. by Rating
-                     2 Power bal. by Pull force  3 Power bal. by Pull force
-                  7= 0-Balance on total power  1-Balance on oarhandle power
-                  8= 0-Force data: chain-pull  1-Force data: normal to shaft
-                 19= 0-No write graphing files 1-Always write graphing files
-                 29= 0-Output English units    1-Output metric (SI) units
-
-            [Type line: Cols. 15-74 _____________________________________]
-            
  Data file: <________.___>

C SHELL DATA: Type- W= ___ kg, L= __ m, S= __ ft^2
  Shell type: ____________________________________________________________]
C  Shell   Bow Saxbrd     Cp,     Cb,   Shell  Resistance_  Head Bound
C length  half   beam   Prism   Block  weight  factors____ -wind layer
C Ls, ft angle     ft  coeff.  coeff.  W, lbm  Water   Air knots    ft
C ------ ----- ------ ------- ------- -------  ----- ----- ----- -----
   00.00 00.00   0.00  0.0000  0.0000  000.00  0.000 0.000  00.0 0.000

C OAR DATA:
    Oar type: ____________________________________________________________]
C    Oar  Handle   Shaft     Oar  Blade_________________________________ 
C length  length  stiff.  weight    Area           Angle  Drag_coeff.___
C Lo, ft  Lh, ft  lbf/ft  lbm/ft  S,ft^2             deg  Normal   Axial
C ------  ------  ------  ------  ------  ------  ------  ------  ------
  00.000   0.000    0.00    0.00   0.000            0.00   0.000   0.000

C OAR DATA (Cont.):                                WATER DATA:
C  Slide   Half-   Total    Arms     Pin  Sculls        Fresh
C excur.  spread    draw    bend   reach  2,  or  Temp. 1, or
C  X, ft      ft   D, ft   B, ft   R, ft  sweeps      F   sea
C ------  ------  ------  ------  ------  ------  ----- -----
    0.00    0.00   0.000    0.00   0.000     2,1   00.0   1,2
C Theta1= 00.00; Theta2= 000.0; dT= 00.0 degrees
- R= Lh *cos(T1); D= R -Lh *cos(T2)
- T1= acos(R /Lh); T2= acos((R -D) /Lh)

C CREW DATA:
   Crew type: ____________________________________________________________]
C               Torso_ Slide_
C  Rower Coxs'n Fract. Ftbrd.  Rower_height_       Peak_pull____   Free Stroke
C weight weight  rower fract.  Actual   Base  Crew Peak-1 Peak-2 period rating
C    lbm    lbm weight weight      in     in  size    lbf    lbf    sec  1/min
C ------ ------ ------ ------  ------ ------  ---- ------ ------ ------ ------
   000.0  000.0  0.400  0.150    0.00   0.00     0  000.0  000.0  0.000  00.00

P STROKE DATA:
C Stroke regime period ratios______________________________________________Ts
C Free_Ta  Drive________________________Td   Free-run______________________Tf
C Torso__  Slide__________________________   Torso___________________________
C  Accel.     Zero  Accel.  Steady  Decel.    Decel.   Accel.  Steady  Decel.
C   phase    phase   phase   phase   phase     phase    phase   phase   phase
C     Ra1      Rl1     Rl2     Rl3     Rl4,5     Rd5 5,   Rr6     Rr7     Rr8
C -------  ------- ------- ------- ------- ^ ------- ^------- ------- -------
    0.000    0.000   0.000   0.000   0.000     0.100    0.000   0.000   0.000

C STROKE DATA (Cont.):                       Slide___________________________
C                                                Lag 5,   Rs6     Rs7     Rs8
C ----------------------------------------   ------- ^------- ------- -------
                                             [0.000]    0.000   0.000   0.000

C STROKE DATA (Cont.):
C Hands/arms_____________________   Oarhandle_pull_   Initial________
C    Zero  Accel.  Steady  Decel.     Surge   Power     Shell  Drive/    Vel.
C   phase   phase   phase   phase     phase   phase     speed  return  expnt.
C     Rh1     Rh2     Rh3   Rh4, 5      Rp1   Rp2, 3   ft/sec   ratio     V^x
C ------- ------- ------- -------^  ------- -------^  ------- -------  ------
    0.000   0.000   0.000   0.000     0.000   0.000     00.00   0.000   2.000

C Oar blade lift and drag coefficients:
  Hydrofoil: _____________________________________________________________]
C Attack angle
C ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- -----
   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0
   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0  90.0
C Lift coefficient
C ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- -----
  0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0
  0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0
C Drag coefficient
C ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- -----
  0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0
  0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0
C Stall angle  Stall point  Drag adj. Lift adj.
C -----------  -----------  --------- ---------
         00.0           00       1.00      1.00

Note:  All data will be input as English units whether or not originally 
       supplied in SI units.
       C, P, -, and x lines are comment lines. 

You may here download the blank input data file, row.dfm.


The Data

Three Job Identification text lines
Job ID-1
Job ID-2
Job ID-3

One Program Control line
Entries as specified above.

Input File Name
The input data file specification.

Shell type
A brief text only summary of the shell.

Shell Data
Shell length: The actual length from ball to stern. ROWING estimates waterline length from estimated bow and stern sheer angles and modifies it as displacement varies.
Bow half angle (at waterline): Used in estimate for form drag addition.
Saxboard beam: At deck (but not if sides flare) or waterline.
Prism coefficient: From hull form (usually known only to the hull designer and similar for similar hull forms.) Used in estimating hull wetted surface area as a function of displacement.
Block coefficient: From hull form (usually known only to the hull designer and similar for similar hull forms). Used in estimating hull draft as a function of displacement.
Shell weight: Except oars, coxswain, and crew. ROWING uses minimum shell weight allowed by the Rules of Rowing if better weight not known.
Resistance factor, water: K in the relation D= KVs^2 where D is the total design displacement drag force at average shell speed Vs. (Usually known only to the hull designer but should probably be part of the published shell specification.)
Resistance factor, air: Unknown. ROWING uses K /10.
Head-wind (knots): Zero unless otherwise specified.
Bound fluid layer thickness: Unknown. Affects the inertial mass of the shell.

Oar type
A brief text only summary of the oars and blades.

Oar Data
Oar length: Handle center of effort to blade center of pressure.
Handle length: Handle center of effort to oarlock pin.
Shaft stiffness: Pounds per foot of deflection at the blade center when loaded as a simple beam with fulcrum at the pin and reaction at the handle center of effort.
Oar weight: Overall weight divided by oar length.
Blade area: Surface area of the blade, except submerged portions of shaft.
Blade angle: Average cant angle between shaft and blade chord.
Drag coefficient, normal: Normal to blade. Used as initial assumption in blade slip iterations.
Drag coefficient, axial: Used for blade chordal skin friction loss estimates.

Slide excursion: From full compression to full leg extension (rower size dependent).
Half spread: Hull centerline to pin.
Total draw: Total hands excursion from start to finish (includes catch to release distance) (rower size dependent). Moderates oar sweep arc.
Arms bend: Excursion of hands with respect to shoulder (rower size dependent). Moderates torso speed in relation to oarhandle speed.
Pin reach: Distance of hands "through the work" at the start (rigging dependent). Moderates catch bow angle.
Sculls or sweeps: 2 or 1 oar per rower.
Water temperature, F: Default 56F.
Water composition: Fresh or sea.

Crew type
A brief text only summary of the crew.

Crew Data
Rower weight: Including clothing.
Coxswain weight: Including clothing.
Torso fraction of rower weight: Fraction of rower weight assigned to the torso and head (from cadaver studies).
Footboard fraction weight: Fraction of lower body weight assigned to the footboard (the boat).
Rower actual height, and:
Rower base height: Ratio used in studying effect of rower size on draw, slide excursion, etc.
Crew size: No. of rowers in crew.
Peak pull; P1: Value of first oarhandle pull peak.
Peak pull; P2: Value of second oarhandle pull peak.
Free period: Fixes length of recovery period (cannot be specified if rating is fixed)
Stroke rating: Fixes rating (cannot be specified if free period is fixed).

Stroke Data
Specifies the time spent in the subject motion regime as a fraction of the total time available for all parts of the same regime, e.g., the excursion of the slide from full leg compression to full leg extension comprising zero motion, acceleration, constant velocity, and deceleration segments. These motions (slide, torso, hands/arms, and force profile) are currently best specified by Atkinsopht and are used to adjust the shell speed profile to match those found in the field if available.

Initial shell speed: An estimate of the final initial shell speed (not the average speed) in order to speed iteration convergence.
Initial drive/return ratio: An estimate of the final drive/return ratio in order to speed iteration convergence.
Velocity exponent: The exponent (usually 2.0) applied to the velocity in the equations of motion. There is some indication that a better model can be obtained with exponents other than 2.0 (such as 1.85) but there is not yet enough field trial data to confirm another value.

Oar blade lift and drag coefficients
The best currently available data are those of a flat plate, totally immersed. See Oarblade Lift and Drag.


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