microchannel

saeedjack · September 18, 2012, 12:23

Hi,
I have a 3-D micro channel heat sink, having a bulk from copper, in which the channels are constructed. The fluid, flowing through the channels, is water-liquid. This structure is meshed in Gambit.
The boundary conditions are as followed:
v-in = 1 (m/s)
T-in = 300 (Kelvin)
P-out = 1 (atm)
Heat flux (coming from the bottom of the bulk) = 2.7 (MW/m2)
These boundary conditions are assigned in Fluent, along with laminar flow. The model used is energy equation. The mutual wall between the fluid and the solid bulk is assigned as coupled, in the boundary conditions. For fluid all the three options (stationary, moving reference frame, and moving mesh) are tested. There is a problem in the result of the converged iterations; the fluid enters the channels with input temperature 300 K, and exits with the same temperature, and all of the characteristics of the output fluid are just like the input ones. I’ll be so grateful if someone can help me. This is my email, for any help from you: saeedezadi882@yahoo.com.
Thanks a lot,
Saeed

P9408 · September 18, 2012, 21:59

How about your geometry

saeedjack · September 19, 2012, 08:25

Thanks for your attention. I have uploaded the image of the heat sink in the "Microchannel Heat-sink" album, in my profile. the fluid comes in from the hole above, and exits from the holes at the two ends of the channels.
the temperature of the fluid doesn't have a substantial change, at the cross section of the channels, just a thin layer of fluid is a little heated. the situation doesn't change even by raising the heat flux to 9.9 (MW/m2). I have uploaded the simulation result of the temperature at different cross sections along the channels, in the mentioned album. but the pressure and velocity have some changes.

saeedjack · September 21, 2012, 04:33

I have uploaded the image of the heat sink in the "Microchannel Heat-sink" album, in my profile. the fluid comes in from the hole above, and exits from the holes at the two ends of the channels.
the temperature of the fluid doesn't have a substantial change, at the cross section of the channels, just a thin layer of fluid is a little heated. the situation doesn't change even by raising the heat flux to 9.9 (MW/m2). I have uploaded the simulation result of the temperature at different cross sections along the channels, in the mentioned album. but the pressure and velocity have some changes.

September 18, 2012, 12:23	microchannel	#1
saeedjack New Member saeed Join Date: Apr 2012 Posts: 9 Rep Power: 14	Hi, I have a 3-D micro channel heat sink, having a bulk from copper, in which the channels are constructed. The fluid, flowing through the channels, is water-liquid. This structure is meshed in Gambit. The boundary conditions are as followed: v-in = 1 (m/s) T-in = 300 (Kelvin) P-out = 1 (atm) Heat flux (coming from the bottom of the bulk) = 2.7 (MW/m2) These boundary conditions are assigned in Fluent, along with laminar flow. The model used is energy equation. The mutual wall between the fluid and the solid bulk is assigned as coupled, in the boundary conditions. For fluid all the three options (stationary, moving reference frame, and moving mesh) are tested. There is a problem in the result of the converged iterations; the fluid enters the channels with input temperature 300 K, and exits with the same temperature, and all of the characteristics of the output fluid are just like the input ones. I’ll be so grateful if someone can help me. This is my email, for any help from you: saeedezadi882@yahoo.com. Thanks a lot, Saeed

September 21, 2012, 04:33	Thanks for your attention	#4
saeedjack New Member saeed Join Date: Apr 2012 Posts: 9 Rep Power: 14	I have uploaded the image of the heat sink in the "Microchannel Heat-sink" album, in my profile. the fluid comes in from the hole above, and exits from the holes at the two ends of the channels. the temperature of the fluid doesn't have a substantial change, at the cross section of the channels, just a thin layer of fluid is a little heated. the situation doesn't change even by raising the heat flux to 9.9 (MW/m2). I have uploaded the simulation result of the temperature at different cross sections along the channels, in the mentioned album. but the pressure and velocity have some changes.

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September 18, 2012, 21:59		#2
P9408 New Member Thanathat Join Date: Mar 2009 Posts: 7 Rep Power: 17	How about your geometry

September 19, 2012, 08:25		#3
saeedjack New Member saeed Join Date: Apr 2012 Posts: 9 Rep Power: 14	Thanks for your attention. I have uploaded the image of the heat sink in the "Microchannel Heat-sink" album, in my profile. the fluid comes in from the hole above, and exits from the holes at the two ends of the channels. the temperature of the fluid doesn't have a substantial change, at the cross section of the channels, just a thin layer of fluid is a little heated. the situation doesn't change even by raising the heat flux to 9.9 (MW/m2). I have uploaded the simulation result of the temperature at different cross sections along the channels, in the mentioned album. but the pressure and velocity have some changes.