Piping enhancement for backflow prevention in a multiple loop, metal cooled nuclear reactor system

1. A sodium-cooled nuclear reactor comprising:

at least one electromagnetic pump assembly, the electromagnetic pump assembly including, a backflow reduction pipe including,

an inlet,

an outlet,

at least one tubular section having a first length and a first diameter, the at least one tubular section between the inlet and the outlet; and

at least one fluid diode section between the inlet and the outlet and configured to restrict backflow, the at least one fluid diode section including,

a first section having a second diameter at a largest point of the first section, and

a second section having a third diameter at a largest point of the second section,

the first section closer to the inlet than the second section, the first section having a first radius at a widest point thereof, the second section having a second radius at a widest point thereof, the first radius being about 1.9 to about 2.2 times the second radius of the second section, and the first section and the second section being generally frustoconical in cross-section.

2. The sodium-cooled nuclear reactor of claim 1 , wherein the second diameter is larger than each of the third diameter and the first diameter.

3. The sodium-cooled nuclear reactor of claim 1 , wherein the at least one fluid diode section has a second length and the second section has a third length, and wherein the second length is about 1.9 to about 2.2 times the third length of the second section.

4. The sodium-cooled nuclear reactor of claim 1 , wherein the at least one fluid diode section has a second length, and wherein the second length of the at least one fluid diode section is about 2.1 to about 2.4 times the first radius of the first section.

5. The sodium-cooled nuclear reactor of claim 1 , wherein the first section has a larger diameter towards an inlet end of the pipe and a smaller diameter towards an outlet end of the pipe.

6. The sodium-cooled nuclear reactor of claim 1 , wherein the first section and the second section each have a larger diameter towards an inlet end of the pipe and a smaller diameter towards an outlet end of the pipe and wherein the first section includes a lobe, a portion of a length of the lobe overlapping with a portion of a the length of the at least one tubular section along a length of the backflow reduction pipe.

7. The sodium-cooled nuclear reactor of claim 1 , wherein the backflow reduction pipe includes a plurality of fluid diode sections along a length of the backflow reduction pipe.

8. The sodium-cooled nuclear reactor of claim 7 , wherein at least one of the plurality of fluid diode sections is centrally located along the length of the backflow reduction pipe.

9. The sodium-cooled nuclear reactor of claim 7 wherein at least one of the plurality of fluid diode sections is located adjacent the inlet of the backflow reduction pipe.

10. The sodium-cooled nuclear reactor of claim 7 , wherein at least one of the plurality of fluid diode sections is located adjacent the outlet of the backflow reduction pipe.

11. The sodium-cooled nuclear reactor of claim 7 , wherein the backflow reduction pipe includes a plurality of tubular sections, and wherein at least one of the plurality of tubular sections is between adjacent ones of the plurality of fluid diode sections.

12. The sodium-cooled nuclear reactor of claim 1 , wherein a flow from the outlet to the inlet undergoes a pressure drop ranging from about 20 psi to about 25 psi based on an internal structure of the backflow reduction pipe.

13. The sodium-cooled nuclear reactor of claim 1 , wherein a flow from the inlet to the outlet undergoes a pressure drop ranging from about 5 psi to about 8 psi based on an internal structure of the backflow reduction pipe.