25-04-2012, 11:45 AM
Selecting a Heat Exchanger
Selecting a Heat Exchanger.doc (Size: 242.5 KB / Downloads: 80)
Select the heat exchanger product series
Choose an aluminum, copper or stainless steel heat exchanger based on the fluid compatibility. Aluminum tubing is usually used with light oils, or ethylene glycol and water solutions. Copper is normally used with water. Stainless steel is used with deionized water or corrosive fluids.
Select the appropriate heat exchanger model
Refer to the thermal performance graphs for the heat exchangers selected (See performance graphs for copper heat exchangers - 6000 series, copper heat exchangers - OEM Coils, stainless steel heat exchangers - Aspen Series, stainless steel heat exchangers - 4000 Series and oil coolers). Any heat exchanger that exceeds 56 W/°C at 2 gpm (using a standard fan) would be acceptable. As shown in the following graph, Lytron’s 6210 exceeds the required performance.
Determine the liquid pressure drop
From the data given, we know our pump needs to supply water at 2 gpm. Using the liquid side pressure drop chart for the 6210 curve, the point where a vertical line at the 2 gpm point on the x-axis intersects with the 6210 curve reveals that the liquid pressure drop through the 6210 is 8 psi (0.55 bars). The pump selected must overcome this pressure drop to ensure a 2 gpm flow.
Cooling Air
In cabinet cooling applications, the air is hotter than the liquid. In this case, the ITD is the difference between the hot air entering the heat exchanger and the cold liquid entering the heat exchanger. You may need to calculate the temperature rise using the heat load and the temperature of the cool air entering the cabinet.
Selecting a Heat Exchanger.doc (Size: 242.5 KB / Downloads: 80)
Select the heat exchanger product series
Choose an aluminum, copper or stainless steel heat exchanger based on the fluid compatibility. Aluminum tubing is usually used with light oils, or ethylene glycol and water solutions. Copper is normally used with water. Stainless steel is used with deionized water or corrosive fluids.
Select the appropriate heat exchanger model
Refer to the thermal performance graphs for the heat exchangers selected (See performance graphs for copper heat exchangers - 6000 series, copper heat exchangers - OEM Coils, stainless steel heat exchangers - Aspen Series, stainless steel heat exchangers - 4000 Series and oil coolers). Any heat exchanger that exceeds 56 W/°C at 2 gpm (using a standard fan) would be acceptable. As shown in the following graph, Lytron’s 6210 exceeds the required performance.
Determine the liquid pressure drop
From the data given, we know our pump needs to supply water at 2 gpm. Using the liquid side pressure drop chart for the 6210 curve, the point where a vertical line at the 2 gpm point on the x-axis intersects with the 6210 curve reveals that the liquid pressure drop through the 6210 is 8 psi (0.55 bars). The pump selected must overcome this pressure drop to ensure a 2 gpm flow.
Cooling Air
In cabinet cooling applications, the air is hotter than the liquid. In this case, the ITD is the difference between the hot air entering the heat exchanger and the cold liquid entering the heat exchanger. You may need to calculate the temperature rise using the heat load and the temperature of the cool air entering the cabinet.