Design and Machining of Copper Specimens With Micro Holes for Accurate Heat Transfer Measurements.
Design and Machining of Copper Specimens With Micro
Holes for Accurate Heat Transfer Measurements.
(9385 K)
Kedzierski, M. A.; Worthington, J. L., III
Experimental Heat Transfer, Vol. 6, 329-344, 1993.
Sponsor:
Department of Energy, Washington, DC
Keywords:
copper; heat transfer; equations; wall temperature;
temperature gradients; drilling
Abstract:
This article presents a technique that has been
developed specifically for drilling 0.5334-mm-diameter,
19-mm-deep holes in copper for use in temperature
measurement. The holes accept thermocouples, which are
used for the measurement of the temperature gradient and
the wall temperature of the specimen. Errors due to the
intrusion of the probe, and the finite size and mass of
the probe, are reduced as the diameter of the probes is
reduced. A machining procedure for drilling deep micro
holes in copper cannot be found in conventional tests,
this article advocates holes that are deeper than those
traditionally recommended. This article is written for
both machinists and experimentalists. Both heat
transfer and maching criteria are considered. The
necessary equipment and their specifications are
discussed. Special attention is given to specifying
drilling speeds, feed rates, and lubricants.
Step-by-step drilling instructions are given. An
analysis is performed to reveal the important parameters
for reducing the errors associated with the uncertainty
in the location, the relative position of the
thermocouples, and the individual temperature
measurements.
Building and Fire Research Laboratory
National Institute of Standards and Technology
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