Learning Forum

[António Oliveira]

I want to analyze an electric heater. It is defined by a tube in which the water circulates inside and I have a power supplied to the external surface of the tube. I want to create an expression for the mass flux rate that is associated with the temperature and the defined power. In this case, I was thinking of using the following expression, m.= P/(C.ΔT), so that the flow rate varies according to the outlet temperature and is thus adjusted so that the desired temperature is reached throughout the simulation.

Is it possible to carry out this analysis? Because I've already tried to write the expression for the flow, but the problem is that as the simulation hasn't been run yet there is no value and so I'm getting the floating point exception error. 

Basically I want to set an initial outlet temperature, but then the simulation should be able to change the flow depending on the temperature results at the outlet to reach the desired temperature. 

 

Thanks.

[RG]

Hi,

Sorry I didnt understand your question fully. However with some understanding below is my thought. with equation mentioned above you may get outlet temp based on given mass flow rate, in other words you can also calculate mass flow rate based on desired temp at given heat source. If you want to increase mass flow rate keeping eye on outlet temp, then you can use conditional expression (e.g. if statement). If temp @ outlet is higher than desired outlet temp then increase mass flow rate with certain increament.

[Rob]

Given you also have this thread  /forum/forums/topic/flow-through-heater/  I'll lock this one.