US Patent No. 9,832,913

METHOD OF OPERATING A COOLING APPARATUS TO PROVIDE STABLE TWO-PHASE FLOW


Patent No. 9,832,913
Issue Date November 28, 2017
Title Method Of Operating A Cooling Apparatus To Provide Stable Two-phase Flow
Inventorship Timothy A. Shedd, Middleton, WI (US)
Assignee EBULLIENT, INC., Madison, WI (US)

Claim of US Patent No. 9,832,913

1. A method of providing stable operation of a cooling apparatus comprising two-phase bubbly flow, the method comprising:
providing a cooling apparatus comprising:
a primary cooling loop comprising: a pump configured to provide a flow of single-phase liquid coolant at a pump outlet; a
reservoir fluidly connected to the primary cooling loop and located upstream of the pump and configured to store a supply
of single-phase liquid coolant for the pump; and one or more heat sink modules fluidly connected to the primary cooling loop,
wherein each heat sink module is configured to mount on and remove heat from a heat-providing surface;

a first bypass having a first end and a second end, the first end of the first bypass being fluidly connected to the primary
cooling loop downstream of the pump outlet, the second end of the first bypass being fluidly connected to the primary cooling
loop at the reservoir, the first bypass comprising a first heat exchanger and a first pressure regulator, the first pressure
regulator configured to regulate a first bypass flow of the flow of single-phase liquid coolant through the first heat exchanger,
the first heat exchanger configured to subcool the first bypass flow of coolant below a saturation temperature of the coolant;
and

a second bypass having a first end and a second end, the first end of the second bypass being fluidly connected to the primary
cooling loop downstream of the pump outlet and downstream of the first end of the first bypass and upstream of the one or
more heat sink modules, the second end of the second bypass being fluidly connected to the primary cooling loop downstream
of the one or more heat sink modules and upstream of the reservoir, the second bypass comprising a second pressure regulator
configured to regulate a second bypass flow of the single-phase liquid coolant through the second bypass;

setting the first pressure regulator in the first bypass to allow about 30-70% of the flow from the pump outlet to be pumped
through the first bypass as the first bypass flow;

setting the second pressure regulator in the second bypass to allow 15-50% of the flow from the pump outlet to be pumped through
the second bypass as the second bypass flow, wherein a remaining portion of the flow of single-phase liquid coolant is pumped
through the one or more heat sink modules and is transformed into two-phase bubbly flow within the one or more heat sink modules
as heat is transferred to the remaining portion of the flow from the one or more heat providing surfaces.