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Evaluation of an Inexpensive Method of stabilize the Temperature of Machine Tool Components



Mahn-Hee Hahn, M A. Donmez, Johannes A. Soons


One of the best approaches for maintaining uniform temperature across a machine tool structure thus minimizing thermal deformations is removing the heat at the heat sources. This study evaluates the effectiveness of using inexpensive Personal Air Conditioner (PAC) tubing to remove heat from heat sources. The PAC tubing is a soft silicone extrusion with small-perforated slits through which cooling air is transferred. The PAC tubing increases heat dissipation from the heat sources through local forced convection and Coanda-effect cooling. The results of a series of tests conducted on a simulated motor showed that the motor shell temperature was reduced 28 times compared to the natural convection cooling. This leads to a conclusion that PAC tubing may be a viable alternative to cooling the machine tool components to reduce the thermal deformations.
NIST Interagency/Internal Report (NISTIR) - 7292
Report Number


coanda-effect, convection heat transfer, machine tool component, PAC tubing, simulated motor, temperature


Hahn, M. , Donmez, M. and Soons, J. (2006), Evaluation of an Inexpensive Method of stabilize the Temperature of Machine Tool Components, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 18, 2024)


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Created February 1, 2006, Updated November 10, 2018