heat transfer to a thin cylinder rod

[soya]

Dear friends,
I would to like to know how to calculate the heat transfer to a cylinder rod during the quencing process after the rod is being heated to 850 degress Celcius.

Thanks.

 

[sailoday28]

Please describe the quenching process?
Water, air, oil. Temp and flow of quenching fluid.

 

[amorrison]

See "Heat Transfer" by J.P. Holman - a standard engineering heat transfer course textbook.

Look up "Heisler Chart" in the Index

 

[soya]

The cylinder rod(carbon steel) has diameter of 0.025m and length of 0.1m.
Itis heated upto 850 degrees Celcius and sprayed with water(20 degrees Celcius) at the bottom of the cylinder(quenching process).

How to determine the cooling rate at the centre of this cylinder?

Should I consider the heat tranfer of the rod to air and water separately for the two dimensional heat flow?

How to determine the Biot Number?Should I consider two Biot Numbers, one is for air and the other one is for water?

 

[EdStainless]

Sounds a lot like a Jominy bar, 1" od x 4" long.
You can always look up standard quench hardnening curves for a good estimate.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[sailoday28]

Should I consider the heat tranfer of the rod to air and water separately for the two dimensional heat flow?
FOR THIS 2D TRANSIENT, YES.

How to determine the Biot Number?Should I consider two Biot Numbers, one is for air and the other one is for water?
I WOULD CONSIDER HEAT TRANS COEF FOR BOTH AIR AND WATER.
THIS CAN BE MESSY- ESPECIALLY WITH NATURAL CONVECTION AND RADIATION FOR THE AIR SURFACE.