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III. THE SCALES OF THE BARATARIA BAY MODEL 



The scales of the Barataria Bay model are based primarily 

 on the equations of kinematic similarity due to Froude. These 

 equations concern the relationships between gravitationally 

 energized fluid systems in a state of continuous quasi- hydrostatic 

 equilibrium. In an estuary like Barataria Bay there are two domi- 

 nantly gravitational factors controlling the circulation; the 

 tides and the drainage of rainfall. Wind stress is also present 

 and scaled to the model since it produces very significant water 

 motions, but since this force is not gravitational its scaling 

 transcends kinematic relationships. 



Once the similarity of circulation in the main bodies of 

 water is established in a model it is possible to introduce an 

 indicator to trace the progress of suitably scaled quantities of 

 industrial discharge under a variety of simulated natural condi- 

 tions. This was the purpose for which the Barataria Bay model was 

 built . 



The notation used in scaling relationships is similar to 

 ordinary physical notation except that all symbols that apply to 

 the prototype are followed by a subscript "p" and those applying 

 to the model are followed by a subscript "m. " Scaling ratios are 

 usually diraensionless and followed by a subscript "r" defined for 

 any q'uantity J as 



