Interim Report - 5JUL95

As I mentioned this morning, I succeeded today in getting 
my Potapov device equipped with a recirculation line 
(formerly called a bypass line) and a diameter reduction 
at the end of the main swirl tube.  This diameter 
reduction is apparently standard issue but my unit did 
not have it.  I connected the recirc line into the main 
swirl tube just before the diameter reduction (as shown 
in about half of the photos).  As mentioned before, my 
recirc line has an area of .185 of the main swirl tube 
area and the diameter reduction produces an outlet area 
of about 0.5 of the main swirl tube area.

For the first series of tests, I did not restrict the 7.5 
hp pump in any way. The inlet pressure was 60 psi and the 
flow rate was very high (probably about 100 gpm...I'll 
measure it tomorrow).  This condition loaded the pump 
heavily and, as a result, the heating rate was relatively 
rapid.  A pressure/vacuum gauge in the recirc line very 
near the main vortex chamber showed a steady 10" of Hg 
vacuum (about 1/3 atmosphere negative pressure) during 
operation.  The results of three efficiency 
determinations are plotted as "r" on the graph below 
which is otherwise a copy of the graph from our latest 
report.

   .
   .
 80-      nv
O  .       n   n                               
V  .                                            
E  .                  av                           
R  .             a                             
A70-                       a                    
L  .                                           
L  .                                              
   .                             c            
E  .                             a             
F60-                                               
F  .                                 r         
I  .                                  xv a     
C  .                                              
I  .                                       r    
E50-                                          a  
N  .   r = 1st recirc line tests               
C  .   n = 106 gpm (P device)                     
Y  .   a = 54 gpm (P device)                          
   .   c = 65 gpm (P device)                           
%40-   x = 65 gpm+air (P device)                 r  vc
   .   v = 60 gpm (gate valve)                        
   .                                                  
   |.........|.........|.........|.........|.........|...
   2         3         4         5         6         7
   0         0         0         0         0         0
                        AVERAGE BATH TEMPERATURE (C)

As you can see, there is no tendency for the new "r" 
points to lie above the curve (which would be an 
indication of energy gain in the Potapov device).  If 
anything, the "r" points lie a bit below the curve.  This 
is not surprising in view of the increased area for heat 
loss provided by the recirc line itself.

Conclusion:

It is not sufficient just to HAVE a recirculation line to 
see the Potapov effect.  There are some other critical 
parameters that I have not yet properly adjusted.

New Directions:

Although a bit counter-intuitive, I will go ahead and 
arrange the necessary restriction so my flow rate will be 
within the range published in the instruction manual for 
the Yusmar-1.  Any other suggestions?

Engineering Note:  Yes, it IS possible to achieve water 
tight connections with standard EMT conduit fittings if 
the ferrules are replaced with O-rings!