Nanofluids for heat transfer applications

Patent metadata

Field	Value
Publication number	US-9937503-B2
Application number	US-201114241263-A
Country	US
Kind code	B2
Filing date	Dec 8, 2011
Priority date	Aug 26, 2011
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

According to an implementation of the present subject matter, a method for producing stable nanofluids is described. The method includes mixing of a base fluid with a dispersant and a metal oxide powder to form a primary mixture. The base fluid is a heat transfer fluid and the metal oxide powder includes particles of size greater than 100 nm. The method further includes grinding the primary mixture to obtain a concentrated nanoparticle suspension where the dispersant is added to the primary mixture during the grinding after every pre-determined time period.

First claim

We claim:

1. A method for producing nanofluids, the method comprising:
mixing a base fluid with a dispersant to form a first mixture;
mixing the first mixture with a metal oxide powder in the range of 30 wt %-40 wt % to form a primary mixture, wherein the base fluid is a heat transfer fluid and the metal oxide powder includes particles of size greater than 100 nm;
grinding the primary mixture to obtain a concentrated nanoparticle suspension, wherein the dispersant is added to the primary mixture during the grinding after every predetermined time period; and
analyzing size of the metal oxide particles during grinding after every predetermined time period.

2. The method as claimed in claim 1 , wherein the metal oxide powder includes particles of at least one metal oxide.

3. The method as claimed in claim 1 , wherein average size of the metal oxide particles is less than 100 nm.

4. The method as claimed in claim 1 , wherein the method further comprises:
diluting the concentrated nanoparticle suspension by adding the base fluid and the dispersant to produce a nanofluid; and
dispersing the diluted nanoparticle suspension to form a stable nanofluid.

5. The method as claimed in claim 4 , wherein the dispersing is done using one of ultrasonication and magnetic stirring.

6. The method as claimed in claim 4 , wherein the heat transfer efficiency of the stable nanofluid is greater than the heat transfer efficiency of the base fluid by 1% to 60%.

7. The method as claimed in claim 4 , wherein the heat transfer efficiency of the stable nanofluid remains substantially constant over multiple heating cooling cycles.

8. The method as claimed in claim 1 , wherein the grinding the primary mixture comprises:
wet milling the primary mixture; and
analyzing, periodically, the primary mixture during the wet milling to measure the size of the metal oxide powder particulates.

9. The method as claimed in claim 8 , wherein the wet milling is done using one of a ball mill and a planetary mill.

10. The method as claimed in claim 1 , wherein the mixing further comprises dispersing the primary mixture to form a primary mixture slurry.

11. The method as claimed in claim 10 , wherein the dispersing is done using one of ultrasonication and magnetic stirring.

12. The method as claimed in claim 1 , wherein the base fluid is one of water, a polyol, a glycol, an alcohol, an oil, and a combination thereof.

13. The method as claimed in claim 1 , wherein the dispersant is one of a carboxylic acid, an ester, an ether, an alcohol, sugar, sugar derivatives, a phosphate, an amine, and a combination thereof.

14. The method as claimed in claim 2 , wherein the metal forming the at least one metal oxide is one of titanium, aluminum, iron, silicon, zirconium, and zinc.

Assignees

• Rai Beena
• Chiney Abhinandan
• Ganvir Vivek
• Pradip
• Tata Consultancy Services Ltd

Inventors

• Rai Beena
• Chiney Abhinandan
• Ganvir Vivek
• Pradip

Classifications

• C09K5/10 Primary

  Liquid materials · CPC title

• B02C25/00

  Control arrangements specially adapted for crushing or disintegrating · CPC title

• B02C23/06 Primary

  Selection or use of additives to aid disintegrating · CPC title

• B02C23/36

  the crushing or disintegrating zone being submerged in liquid · CPC title