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The issue is as fresh as ICCF 16.

New Analysis of MIT Calorimetric Errors
Melvin H. Miles1 and Peter Hagelstein2
1Dixie State College, St. George, UT 84770, USA
2Massachusetts Institute of Technology,
Cambridge, MA, 02139, USA
The MIT calorimetry published in 1990 [1] had a major impact in
convincing scientists that the anomalous excess enthalpy reported
by Fleischmann and Pons in Pd/D systems was due to various
errors. Nevertheless, the MIT heat conduction calorimetry has a
stated sensitivity of 40 mW while the Fleischmann-Pons Dewar
calorimetry achieved a sensitivity of 0.1 mW. [2] Additional
information about the MIT calorimetry [3] has allowed a more
detailed analysis. The major new finding is that the walls of the MIT
calorimetric cell were so well insulated with glass wool (2.55 cm in
thickness) that the major heat transport pathway was out of the cell
top rather than from the cell into the constant temperature water
bath. The walls of any heat conduction calorimetric cell could be
insulated to the point that almost all heat flow would be out of the
cell top .

From the published MIT date [1,3], an unusually small conductive
cell constant of kC=0.088 W/K is calculated that reflects the thick cell
insulation. For the typical MIT total input power of 1.76 W, only
0.68 W flows across the thick insulation of the water bath. It is
calculated that 1.02 W flows through the cell top and 0.06 W flows
through the cell bottom. The heat flow pathways, therefore, are
39% through the cell wall, 3% through the cell bottom, and 58%
through the cell top. The large heat flow through the top of the MIT
calorimeter accounts for their reports of large electrolyte level
effects and marked effects of the room temperature variations. [1,3]
Analysis of the Fleischmann-Pons Dewar cell shows that under
conditions similar to the MIT experiments (Tcell=46.0 °C, Tbath=26.0
°C), almost all of the heat flow would be from the Dewar
calorimetric cell to the constant temperature bath as desired .

Furthermore, the sensitivity of the Fleischmann temperature
measurements were 0.001°C versus a sensitivity of only 0.1°C for
the MIT calorimetric cell. The evaluation of the calorimetric
equations and data analysis methods leads to the clear conclusion
that the Fleischmann-Pons calorimetry was far superior to that of
MIT. Even today, no electrochemical calorimeter exceeds the
accuracy and sensitivity reported by Fleischmann. [2]
References:
[1] M.S. Wrighton et.al., J. Fusion Energy, 1990, 9, 133 .

[2] M. Fleischmann and M.H. Miles, Proceedings of ICCF-10, 2003,
pp 247-268
[3] S.C. Luckhardt, Technical Appendix to J. Fusion Energy (1990),
MIT Report PFC /RR-92-7, May 1992.