6
Circulating device
User’s
equipment
T2: Return temperature
T1: Outlet temperature
L
∆
T = T2 – T1
Water bath
V
After 15 min, cool 30
°
C down to 20
°
C.
20
°
C
Temperature [
°
C]
Density
ρ
[kg/L]
Specific heat C [J/(kg·K)]
10
1.03
3.93 x 10
3
20
1.03
3.95 x 10
3
30
1.02
3.97 x 10
3
40
1.02
3.98 x 10
3
50
1.01
4.00 x 10
3
60
1.01
4.02 x 10
3
Precautions on Model Selection
Guide to Model Selection
Circulating Fluid Typical Physical Property Values
Ethylene Glycol Solution 20%
Obtain the temperature difference between inlet and outlet by circulating the fluid inside the user’s equipment.
Heat generation amount
Q
Circulating fluid temperature difference
∆
T (= T2 – T1)
Circulating fluid outlet temperature
T1
Circulating fluid return temperature
T2
Circulating fluid flow rate
L
Circulating fluid
: Unknown
: 0.8
°
C (0.8 K)
: 25
°
C (298.15 K)
: 25.8
°
C (298.95 K)
: 3 L/min
: Water
Density
γ
: 1 x 10
3
kg/m
3
Specific heat
C: 4.2 x 10
3
J/(kg·K)
Q =
∆
T x L x
γ
x C
60 x 1000
0.8 x 3 x 1 x 10
3
x 4.2 x 10
3
60 x 1000
= 167 W
=
200 W
Cooling capacity = Considering a safety factor of 20%,
167 W x 1.2 =
Water
Density
γ
: 1 x 10
3
[kg/m
3
]
Specific heat C: 4.2 x 10
3
[J/(kg
•
K)]
Cooled substance total volume
V
Cooling time
h
Cooling temperature difference
∆
T
Circulating fluid
Cooling capacity = Considering a safety factor of 20%,
93.3 W x 1.2 = 112 W
Q =
∆
T x V x
γ
x C
h x 60 x 1000
=
10 x 2 x 1 x 10
3
x 4.2 x 10
3
15 x 60 x 1000
= 93.3 W
: 2 L
: 15 min
: Temperature difference: 10
°
C (10 K). Cool from 30
°
C (303 K) to 20
°
C (293 K).
: Water
Density
γ
: 1 x 10
3
kg/m
3
Specific heat
C: 4.2 x 10
3
J/(kg·K)
∗
Refer to the information shown below for the typical
physical property values by circulating fluid.
Example 2 When the heat generation amount in the user’s equipment is not known.
Example 3 When cooling the object below a certain temperature in certain period of time.
Model Selection
Series
HECR
The flow rate of the circulating fluid depends on the pressure loss of the user’s equipment and the length, diameter and
resistance created by bends in the circulating fluid piping etc. Check if the required flow rate of circulating fluid can be obtained
before selecting.
