TM No. 377 



Tovins Tank Calibrations of OMDUM III and LIMDUM I (individual 

 meters ) - The following are tabulations of the tow tank calibration data 

 of the OMDUM III and LIMDUM I ( individual meters ) obtained with the 

 Capt. Miry P. Converse Tow Tank, in Marion, Mass. Details of the ex- 

 perinsntal setup and procedures are given in chapter II. The data pre- 

 sented were used to prepare calibration curves in figure 11-21. An ex- 

 planation of the table headings follows. 



Serial: The numbered sequence of runs of steady velocity response. 

 N or S indicates the towing direction as north or south. 



Vrji (cm sec"-^): The average speed of the carriage between two fixed 

 points on the tank. 



Vn Vg, and V^ (cm sec~l): These are carriage velocities calculated 

 at the HDe ginning, middle, and end of the steady speed towing. They are 

 derived from measurements of the drive shieve rotation and knowledge of 

 its circumference. 



Tp (msec cycle"^): This is the average interval of time between volt- 

 age pulses from the ducted meter. 



The value of angle 6 subtended by the cylinder axis and the towing 

 direction is also given in the tables. It is estimated that the uncer- 

 tainty in e is about +2°. 



Series 1. This series comprises calibration data for steady towing 

 of individual ducted meters . 



0=0' 



% V, 



12.6 12.5 



9.1 9.2 



8.2 8.1 

 7.0 7.0 

 9.5 9.6 



12.3 12.3 

 14.6 14.4 

 18.2 18.1 



27.8 27.5 



28.4 28.2 

 54.4 53.7 

 47.0 47.4 

 71.0 69.8 

 79.0 



64.9 67.1 

 65.8 65.9 65.7 65.5 47.52 



C-1+ 



