Equation of state and temperature measurements for shocked nitromethane

A thermodynamically consistent equation of state (EOS) was developed for un reacted liquid nitromethane (NM). The specific heat c(upsilon), the coeffic ient of thermal pressure (partial derivativeP/partial derivativeT)(upsilon) , and the isothermal bulk modulus B-T, were modeled as functions of tempera ture and volume using existing experimental data. To test our EOS predictio ns, temperature measurements using time-resolved Raman spectroscopy were ob tained from NM subjected to stepwise loading. In contrast to previous EOS d evelopments, calculations using our EOS show good agreement with the measur ed temperatures. Comparison with previous EOS models shows that simplifying assumptions, such as holding (partial derivativeP/partial derivativeT)(ups ilon) or Gamma/upsilon constant, lead to significant inaccuracies in temper ature predictions for shocked NM. The assumption that the Gruneisen paramet er Gamma is a function of volume only is not consistent with our EOS. (C) 2 000 American Institute of Physics. [S0021-9606(00)51141-6].