Systems and methods for heat transfer using heat pipes

1 . A system for changing a temperature of a packaged biologic substance, the system comprising:

a chamber configured to receive the packaged biologic substance;

a refrigeration assembly configured to generate an airflow through the chamber to change the temperature of the packaged biologic substance; and

an auxiliary heat exchanger at least partially positioned in the chamber, the auxiliary heat exchanger comprising:

at least one heat pipe that is configured to transfer heat between the packaged biologic substance and the airflow;

a first portion that is configured to contact at least a portion of the packaged biologic substance; and

a second portion that is configured to be exposed to the airflow through the chamber,

wherein the second portion extends at a non-zero angle relative to the first portion, and

wherein the second portion is located entirely in the chamber.

2 . The system of claim 1 ,

wherein the system operates at a temperature ranging from about 0° C. to about −40° C.

3 . The system of claim 1 , wherein the first portion is configured to underlie the packaged biologic substance.

4 . The system of claim 1 , further comprising ducting configured to circulate the airflow between the refrigeration assembly and the chamber.

5 . The system of claim 1 , wherein the chamber includes a shelf, and wherein the auxiliary heat exchanger is at least partially integrated into the shelf.

6 . The system of claim 1 , wherein the first portion is configured as a shell that is configured to at least partially enclose the packaged biologic substance.

7 . The system of claim 1 , wherein the auxiliary heat exchanger comprises a plurality of heat pipes,

wherein the at least one heat pipe is one of the plurality of heat pipes,

wherein a first heat pipe of the plurality of heat pipes contains a first refrigerant and is configured to change a phase of the first refrigerant over a first temperature range of the packaged biologic substance,

wherein a second heat pipe of the plurality of heat pipes contains a second refrigerant and is configured to change a phase of the second refrigerant over a second temperature range of the packaged biologic substance, and

wherein the first temperature range is different from the second temperature range.

8 . The system of claim 7 , wherein the first heat pipe contains a first charge of the first refrigerant, wherein the second heat pipe contains a second charge of the second refrigerant, and wherein at least one of:

the first charge is different from the second charge; or

the first refrigerant is different from the second refrigerant.

9 . The system of claim 1 , wherein the at least one heat pipe comprises a slugging heat pipe.

10 . A method of changing a temperature of a packaged biologic substance, the method comprising:

(a) contacting the packaged biologic substance with a first portion of an auxiliary heat exchanger within a chamber, the auxiliary heat exchanger also including a second portion and at least one heat pipe extending between the first portion and the second portion;

(b) generating an airflow through the chamber with a refrigeration assembly; and

(c) circulating the airflow between the chamber and the refrigeration assembly so that the airflow:

(i) contacts the packaged biologic substance in the chamber to transfer heat between the packaged biologic substance and the airflow, and

(ii) contacts the second portion of the auxiliary heat exchanger to transfer heat between the packaged biologic substance and the airflow via the heat pipe, wherein the second portion is configured to be exposed to the airflow through the chamber, the second portion extends at a non-zero angle relative to the first portion, and the second portion is located entirely in the chamber.

11 . The method of claim 10 , wherein (c) further comprises directing the airflow through ducting positioned between the refrigeration assembly and the chamber so that the airflow contacts the second portion of the auxiliary heat exchanger.

12 . The method of claim 10 , wherein (c) further comprises circulating the airflow between the chamber and the refrigeration assembly so that the airflow contacts the second portion of the auxiliary heat exchanger in the chamber.

13 . The method of claim 10 , wherein the auxiliary heat exchanger includes a plurality of heat pipes extending between the first portion and the second portion,

wherein the at least one heat pipe is one of the plurality of heat pipes,

wherein a first heat pipe of the plurality of heat pipes contains a first refrigerant and is configured to change a phase of the first refrigerant over a first temperature range of the packaged biologic substance,

wherein a second heat pipe of the plurality of heat pipes contains a second refrigerant and is configured to change a phase of the second refrigerant over a second temperature range of the packaged biologic substance,

wherein the first temperature range is different from the second temperature range, and

wherein the method further comprises changing a temperature of the airflow with the refrigeration assembly so that:

during a first time period, the temperature of the packaged biologic substance corresponds with the first temperature range of the first heat pipe, and

during a second time period the temperature of the packaged biologic substance corresponds with the second temperature range of the second heat pipe.

14 . The method of claim 10 , wherein (c) comprises freezing or thawing the packaged biologic substance with the airflow.

15 . A system for cooling a packaged biologic substance, the system comprising:

a chamber;

a refrigeration assembly configured to generate an airflow through the chamber to cool the packaged biologic substance in the chamber; and

an auxiliary heat exchanger at least partially positioned in the chamber, the auxiliary heat exchanger comprising:

a first portion that is configured to contact at least a portion of a surface area of the packaged biologic substance;

a second portion that is spaced from the packaged biologic substance,

wherein the second portion is configured to be exposed to the airflow through the chamber,

wherein the second portion extends at a non-zero angle relative to the first portion, and

wherein the second portion is located entirely in the chamber; and

a heat pipe extending between the first portion and the second portion, wherein the heat pipe contains a refrigerant that is configured to change phase to transfer heat from the first portion to the second portion to cool the packaged biologic substance.

16 . The system of claim 15 , wherein the first portion is configured to underlie the packaged biologic substance.

17 . The system of claim 15 , further comprising ducting configured to circulate the airflow between the refrigeration assembly and the chamber.

18 . The system of claim 15 , wherein the second portion is engaged with a wall of the chamber.

19 . The system of claim 15 , wherein the auxiliary heat exchanger comprises a plurality of heat pipes,

wherein the heat pipe is one of the plurality of heat pipes,

wherein a first heat pipe of the plurality of heat pipes contains a first refrigerant and is configured to change a phase of the first refrigerant over a first temperature range of the packaged biologic substance,

wherein a second heat pipe of the plurality of heat pipes contains a second refrigerant and is configured to change a phase of the second refrigerant over a second temperature range of the packaged biologic substance, and

wherein the first temperature range is different from the second temperature range.

20 . The system of claim 15 , wherein the system operates at a temperature ranging from about 0° C. to about −40° C.