TOP VIEW OF HEADBAY 



OPERATION OF TIDE GENERATOR 



THE WATER SURFACE IN THE MODEL (A) IS APPRECIABLY HIGHER THAN IN THE SUMP (B). A PUMP (C) LOCATED 

 IN THE SUMP DISCHARGES A CONSTANT AMOUNT OF WATER INTO ONE SIDE OF A DIVIDED HEADBAY (D). DISCHARGE 

 FROM THE MODEL TO THE SUMP IS CONTROLLED BY AN AUTOMATIC VALVE (El. OPERATION OF THE AUTOMATIC VALVE 

 IS DICTATED BY THE TIDE CONTROL (F) LOCATED IN THE MODEL. WHEN THE TIDE IS RISING IN THE MODEL, THE 

 AUTOMATIC VALVE IS ALMOST CLOSED SO THAT MOST OF THE WATER REMAINS IN THE MODEL. WHEN THE TIDE IS FALL- 

 ING IN THE MODEL, THE VALVE IS ALMOST OPEN SO THAT ALL THE WATER FROM THE PUMP, PLUS THE DESIRED AMOUNT 

 OF WATER FROM THE MODEL RETURNS TO THE SUMP, THE TIDE CONTROL MAINTAINS THE PROPER VALVE OPENING AT ALL 

 TIMES AS REQUIRED TO REPRODUCE ANY DESIRED TIDE IN THE MODEL. 



Figure 3-15. Operation of pumped inflow and gravity outflow tide generator. 



TIDE DISPLAY SIGNAL 



TIDE DISPLAY DRUM 



. TIDE CONTROL DRUM 



z 



TIDE DISPLAY 



TIDE ELEVATION 



AT CONTROL POINT 



TIDE CONTROL SIGNAL 



TIDE ELEVATION AT CONTROL POINT 



TIDE HEIGHT DATA 



VELOCITY DATA 



SALINITY DATA 



TEMPERATURE DATA 



HYBRID 

 INTERFACE 



CENTRAL 



PROCESSING 



UNIT 



MAGNETIC 



TAPE 

 HANDLER 



OPERATOR'S CONSOLE 



n 



VALVE POSITION I COMPARATOR 



HYDRAULIC 



A MPLIFIER BUBBLE-TUBE 

 POSITIONER 



niM 



DATA SIGNALS 



(UP TO 8) 



\M. 



TEMPERATURE DATA 



SALINITY DATA 



VELOCITY DATA 



TIDE HEIGHT DATA VELOCITY SALINITY 

 METER METER 



DIGITAL VOLTMETER 



THERMOCOUPLE 



POTENTIOMETER 



^:;^~))PUMP 



Figure 3-16. Automatic Data Acquisition and Control System (ADACS) 



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