| Summary: | The present work is devoted to study cryogenic nitrogen jets in high subcritical conditions. Fuel injection is one of the great challenges in engineering of diesel engines, gas turbines and rocket engines, combining in the last one also the injection of oxidizer. It is widely known that the increase of operation pressures and temperatures increases engine efficiency and reduces fuel specific consumption. Thus, it is a general trend in modern engines the operation in increasingly higher pressures. However at higher chamber pressures the injected fluids may experience ambient conditions exceeding the critical values. Several authors stated that at these conditions the injected fluids suffers a change of its properties, and the traditional two-phase flow models cannot correctly predict the jet behavior at these conditions, thus new computational models are needed for these specific conditions. Barata et al. [18] performed a numerical investigation aimed to evaluate the applicability of an incompressible but variable density model in liquid jets under sub-to-supercritical conditions. The results achieved agree well with the experimental data but they only considered intermediate density ratios from 0.05 to 0.14. The objective of the present work was to extend the investigation of Ref. 18 to lower density ratios from 0.025 to 0.045 which correspond to cases with subcritical chamber pressures. The obtained results agree well with the experimental and numerical data of Chehroudi et al. presented in Ref. 18. It was also found in this work that the computational model does not offers valid results for density ratios lower than 0.025.
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