The thermal conductivity of water as a function of temperature.
Sample data file, CurveExpert 1.0

T(F)  k(BTU/hr-ft-degF)
=============================

32   .319
40   .325 
50   .332 
60   .340  
70   .347  
80   .353  
90   .359  
100  .364  
150  .384  
200  .394 
250  .396  
300  .395  
350  .391  
400  .381 
450  .367 
500  .349  
550  .325 
600  .292