Experimental and numerical investigation on flow condensation process of oxygen jet in crossflow of liquid oxygen

The mixing and condensation process of gaseous oxygen jet in liquid oxygen flow in the outlet pipeline of oxidizer booster pump in liquid rocket engine are studied. In the present study, experiments are performed to investigate oxygen jet condensation in crossflow of liquid oxygen in a vertical pipe. The image of the test section is obtained by visualization device and processed by digital image technology. A computational fluid dynamics (CFD) model is developed to simulate the mixing and condensation process based on multiphase VOF model and Lee phase change model. The experimental results show that, under the current operating conditions, gaseous oxygen forms a crooked jet plume at the outlet of orifices, and then the gas phase gradually condenses, forming discontinuous bubbles downstream. The effects of Reynolds number of liquid oxygen, oxygen mass flux, ambient pressure and liquid oxygen temperature on the gas distribution and axial condensation length are investigated accordingly. The mass transfer coefficient r=10000s⁻¹ which has been verified by the experiment of oxygen jet in liquid oxygen crossflow is obtained and the predicted gas distribution by CFD simulation is in good agreement with the experimental data. The experimental dimensionless axial condensation length is in the rage of 7.3 to 18.2, and a correlation of dimensionless axial condensation length has been modified. Besides, the dimensionless axial condensation length predicted by simulation is less than 13% comparing with experiment. The averaged heat transfer coefficients obtained in experiment and simulation are around 13.89–26.04 kW/(m²K) and 12-67kW/(m²K), which is much lower than the average heat transfer coefficient in the DCC of water. The results of the present investigation will be helpful in designing the pipeline between pumps in liquid rocket engine.