A new unified equation of state for H2O is presented, which includes the revised and extended scaling equation of Levelt Sengers, Kamgar–Parsi, Balfour and Sengers, is continuous over all single phase states of H2O from triple point pressure and temperature to 1000 MPa (or the melting line) and 1000 °C and provides accurate representation of existing thermodynamic data in that range. In addition it provides a smooth transition from singular critical region functions to the nonsingular far-field functions. This is demonstrated by the variations of isochoric specific heat, isothermal compressibility, speed of sound, specific heat ratio and coexistence line properties in the critical region.

Existing data on the condensation of steam and moist air in supersonic nozzles are compared with predictions based on nucleation and drop-growth theory. It is concluded that, if the surface tension is assumed independent of curvature, and the classical liquid-drop theory (based on a stationary liquid drop) is used, the theory is in general agreement with the data. The effects of uncertainties in cluster surface energy and also of the large corrections to nucleation theory due to the ‘gasification’ concept are examined. The gasification correction is in accord with experimental data only if the surface tension is considered to rise significantly with curvature. In neither case can the Tolman or Kirkwood–Buff equations be supported. A review of existing data shows that there is some question as to the appropriate value of the condensation coefficient but this is of little consequence as long as the accommodation coefficient for the liquid–vapour surface is taken to be unity. The usefulness of the nozzle experiments for testing the validity of nucleation theory is demonstrated.

Compressible transient turbulent gaseous jets are formed when natural gas is injected directly into a diesel engine. Multi-dimensional simulations are used to analyze the penetration, mixing, and combustion of such gaseous fuel jets. The capability of multi-dimensional numerical simulations, based on the k-ε turbulence model, to reproduce the experimentally verified penetration rate of free transient jets is evaluated. The model is found to reproduce the penetration rate dependencies on momentum, time, and density, but is more accurate when one of the k-ε coefficients is modified. The paper discusses other factors affecting the accuracy of the calculations, in particular, the mesh density and underexpanded injection conditions. Simulations are then used to determine the impact of chamber turbulence, injection duration, and wall contact on transient jet penetration. The model also shows that gaseous jets and evaporating diesel sprays with small droplet size mix at much the same rate when injected with equivalent momentum injection rate. [S0098-2202(00)02304-X]

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A fundamental equation of state has been formulated for heavy water in the form Ψ = Ψ(p,T) in which Ψ = Helmholtz free energy p = density T = thermodynamic temperature. The complete range of single phase states in the range up to 100 MPa and 600 °C is covered by a single equation which is fitted both to PvT values, for saturated and unsaturated states, and to enthalpy values for saturation states only. The equation is constrained to fit the critical point conditions determined by Blank. It represents all thermodynamic properties of D2O, in the above range of states, within what is believed to be the accuracy of the experimental data.