Coil in tank: outside heat transfer coefficient
Coil in tank: outside heat transfer coefficient
(OP)
Hi,
I would like to ask for your opinion in this: i have a tank with water that i need to heat. I have a circular coil inside it. I'm calculatin the area needed to transfer a certain amount of energy a a determined rate. Therefore i'm calculatin the Overall Heat Trasnfer rate, wich is baes on inside and outside heat transfer coefficients and the pipe wall, also.
My problem is:
1) If the fluid is static inside the tank, what should be my outside heat transfer coefficien: ho ??
2) If the water inside the tank has a certain flowrate as shown in the attached ficgure, how can i calculate the heat transfer coefficient, for a circular coil?
Thanks
htt p://files. engineerin g.com/getf ile.aspx?f older=a76d 0ba9-30b4- 447f-bf68- b6f26ea900 93&fil e=HX_1.jpg
htt p://files. engineerin g.com/getf ile.aspx?f older=878c b8de-e9ea- 4f65-ad61- b9315fa4a0 88&fil e=HX_2.jpg
I would like to ask for your opinion in this: i have a tank with water that i need to heat. I have a circular coil inside it. I'm calculatin the area needed to transfer a certain amount of energy a a determined rate. Therefore i'm calculatin the Overall Heat Trasnfer rate, wich is baes on inside and outside heat transfer coefficients and the pipe wall, also.
My problem is:
1) If the fluid is static inside the tank, what should be my outside heat transfer coefficien: ho ??
2) If the water inside the tank has a certain flowrate as shown in the attached ficgure, how can i calculate the heat transfer coefficient, for a circular coil?
Thanks
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RE: Coil in tank: outside heat transfer coefficient
2)With the tank contents having velocity, look at forced convection heat transfer for for ho. Is this velocity created by an agitator or external circulation pump? Correlations for ho under agitation can be found in Perry's and most agitator references books.
Good luck,
Latexman
RE: Coil in tank: outside heat transfer coefficient
Thank you for the reply.
Comments:
2) As you can see in my 2nd attached file, the velocity in the tank is imposed by an external circulation pump.
My problem is that usually i calculate heat exchangers considering rectangular pipe arrangementes or "triangular" arrangements. In this case we have a circular coil and the fluid stream crosses it from below. This kind of "object" that is crossed by the stream is new to me and i don't know waht calculations must i do...
I hope i was clear enough.
Thanks
RE: Coil in tank: outside heat transfer coefficient