The power required for heating a circulating fluid
The power required for heating a circulating fluid
(OP)
the equation to use to work out the power required for heating a circulating fluid:
Pch = (Qm × Cp ×(t2 − t1) × 1,2) ÷ 860
-Heating power : Pch (kW)
– Mass flow rate : Qm (kg/h)
– Specific heat of fluid : Cp (kcal/kg × °C)
– Inlet temperature : t1 (°C)
– Required outlet temperature : t2 (°C)
– 1,2 : Safety coefficient linked to our manufacturing tolerances and variations in network power
however the system im using is a closed loop so whatever leaves t2 will come back into t1 therefore my t1 temperature will always be changing so how would i calculate it with the constant change ?
any ideas will be helpful
Pch = (Qm × Cp ×(t2 − t1) × 1,2) ÷ 860
-Heating power : Pch (kW)
– Mass flow rate : Qm (kg/h)
– Specific heat of fluid : Cp (kcal/kg × °C)
– Inlet temperature : t1 (°C)
– Required outlet temperature : t2 (°C)
– 1,2 : Safety coefficient linked to our manufacturing tolerances and variations in network power
however the system im using is a closed loop so whatever leaves t2 will come back into t1 therefore my t1 temperature will always be changing so how would i calculate it with the constant change ?
any ideas will be helpful
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RE: The power required for heating a circulating fluid
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RE: The power required for heating a circulating fluid
If you're talking about heating up then you need to use a transient program or do this in a series of small steps.
As noted in your previous post Cp changes with temperature.
This is a transient event with many things changing as the temperature rises (including any heat losses in your circuit). It is not possible to find a simple equation which can calculate this.
If you do the bulk energy method and then divide by a factor of 1.5 you won't be far away providing you heat losses aren't too big.
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RE: The power required for heating a circulating fluid
why would i need to divide the bulk energy by a factor of 1.5?
Also when calculating a object heating up time do i factor in the heat loss which will increase the time or would i put a tolerence of +/- a suitable number to make up for the heat loss ?
RE: The power required for heating a circulating fluid
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: The power required for heating a circulating fluid
"Also when calculating a object heating up time do i factor in the heat loss which will increase the time or would i put a tolerence of +/- a suitable number to make up for the heat loss ?
"
If you are heating it up to ambient? Heat loss will be quite small. Heating it up to 500 degC? A lot more heat loss to ambient...
RE: The power required for heating a circulating fluid
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