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Julabo Determination of Heating/Cooling Power
The following is the general formula for determining necessary heating and cooling requirements of a system.
Formula: Q=mC(T2-T1)/t
where:	m=	mass of bath/reactor fluid
	C=	specific heat of bath/reactor fluid
	T1=	start temperature
	T2=	end temperature
	t=	elapsed time
Directions:	Please substitute your own values as indicated below.

Value
1	20	liters	Enter the volume of the circulator + hoses + reactor jacket volume
2	0	liters	Enter the volume of the reactor (enter zero if not applicable)
3	1	kg/liter	Enter the density of the circulator bath fluid
4	0	kg/liter	Enter the density of the reactor fluid (enter zero if not applicable)
5	1.45	kJ/(kg°C)	Enter the specific heat capacity of the circulator bath fluid
6	0	kJ/(kg°C)	Enter the specific heat capacity of the reactor fluid (zero if not applicable)
7	120	°C	Enter the starting temperature
8	-10	°C	Enter the target temperature
9	14000	seconds	Enter the desired heat-up/cool-down time
10		kW	Enter estimated power losses (this number must be positive)

		Bath Liquid Properties
Value	m1(kg)
11	20	Multiply value 1 times value 3 and enter result here

	C1 (kJ/[kg°C])
12	1.45	Enter value 5 here				Reference Data

		Reactor Liquid Properties				Specific Heat	Density
	m2 (kg)					kJ/(kg°C)	kg/liter
13		Multiply value 2 times value 4 and enter result here			water	4.18	1
					ethanol	2.43	0.783
	C2 (kJ/[kg°C])				methanol	2.49	0.787
14		Enter value 6 here			silicon oil	1.45	1
					aluminum	0.896	2.7
		Customer Requirements			copper	0.385	8.9
Value	t (s)				iron	0.45	7.84
15	14000	Enter value 9 here			lead	0.128	11.31
					silver	0.235	10.47
	T1 (°C)				tin	0.217	5.73
16	120	Enter value 7 here			ammonia	4.8	0.602
					mercury	0.139	13.56
	T2 (°C)				50/50 EG/H20	3.25	1.1
17	-10	Enter value 8 here

Required Heating/Cooling Power				Modified Equation:
				Q=[(m1C1)+(m2C2)][(DT)/t]
	Temperature Change
Value	DT (°C)
18	-130	Subtract value 16 from value 17 and enter result here

19	Nominal Heat Load (kW)	Nominal Heat Load is the calculated load based on the customer's requirements.
	-0.269	Perform the following calculation: [(v11v12)+(v13v14)][(v18)/v15]
20	Total Heat Load (kW)	Total Heat Load is the Nominal Heat Load plus any estimated losses.
	-0.269	If value 19 is positive, add value 10. If value 19 is negative, subtract value 10.

	Heating or Cooling?
20	Cooling!	If value 19 is positive, heating is required. If value is negative, cooling is required.

Important Note: This calculation should only be used as a basis for circulator/chiller selection. Many factors that will influence power requirements are too difficult to quantify, and thus are neglected from this calculation. Actual power requirements will almost always be larger than calculated values.

Additional Notes:
1	Julabo is not responsible for damages/injuries caused by using unapproved bath fluids in circulators/baths/chillers.
2	Julabo is not responsible for damages/injuries resulting from incorrect use of approved bath fluids.
3	Flash points of bath fluids must be above +60°C for transport by plane.
4	Julabo chiller/circulator high temperature warning and safety values should reference fluid flash temperature.
5	Julabo chiller/circulator low temperature warning should reference fluid freezing point or maximum viscosity.
6	Julabo H350 bath oil is intended only for Julabo high temperature sealed systems.

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