Slushes are two-phase solid-liquid single-species cryogenic fluids that exhibit an increased density and a greater heat capacity with respect to the corresponding normal boiling point liquids. These promising features are of large interest for applications that exploit slush as a thermal fluid, like super magnets refrigeration, cryogenic cooling of bio-materials or air conditioning, and for aerospace systems that use slush fluids as fuel or oxidizer. Several programs in the frame of the research on Slush Hydrogen (SLH2) as a new-generation fuel for aerospace propulsion have been started in the past. This work was carried out in the framework of a VKI research activity promoted by the Predict ESA Technology Research Programme, to investigate experimentally and numerically the behavior of slush flows in a representative upper stage feeding line. In this paper, we present a simulation based on a granular two-fluid model on an isothermal solid liquid mixture (slurry) and a Nitrogen slush (SLN2) fluid flowing in a horizontal pipe. A finite-volumes discretization using the software library OpenFOAM was benchmarked against experimental and numerical literature data, to assess the accuracy of the code in predicting pressure drops along the pipe axis and solid particle distribution across the pipe diameter. Moreover, the effects of concentration and inlet velocity are investigated. We show that the numerical model fairly reproduces the literature data in terms of important aspects as the solid volume fraction distribution and the pressure drops, especially for high flow rates.
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 A. Friendlander R. Zubrin and T. L. Hardy “Benefits of slush hydrogen for space missions” Cryogenics vol. 10 no. 5 pp. 372-380 1970.
 C. Sindt A summary of the characterization study of slush hydrogen vol. 10 Cryogenics 1970 pp. 372-380.
 Dumont Etienne Stappert Sven Ecker Tobias Wilken Jascha Karl Sebastian Krummen Sven Sippel and Martin “Evaluation of Future Ariane Reusable VTOL Booster stages” in roceedings of the International Astronautical Congress IAC. 68th International Astronautical Congress Adelaide (2017).
 J. Ishimoto and R. Ono “Numerical study of the two-phase flow characteristics of slush nitrogen” Cryogenics vol. 45 no. 4 pp. 304-316 2005.
 P. Crivellari L. del Monte and F. Gamma “Computational fluidynamics of hydrogen for aerospace vehicles” in 35th Joint Propulsion Conference Los Angeles 1999.
 K. Ohira A. Ota Y. Mukai and T. Husono “Numerical study of flow and heat-transfer characteristics of cryogenic slush fluid in a horizontal circular pipe (SLUSH-3D)” Cryogenics vol. 52 no. 7 pp. 428-440 2012.
 D. P. Hill “The computer simulation of dispersed two-phase flow” University of London 1998.
 H. Rusche “Computational fluid dynamics of dispersed two-phase flows at high phase fractions” University of London 2003.
 D. Gidaspow Multiphase flow and fluidization: continuum and kinetic theory descriptions Academic press 1994.
 B. G. M. van Wachem “Derivation implementation and validation of computer simulation models for gas-solid fluidized beds.” 2000.
 P. C. Johnson and R. Jackson “Frictional–collisional constitutive relations for granular materials with application to plane shearing” Journal of fluid Mechanics vol. 176 pp. 67-93 1987.
 D. R. Kaushal and Y. Tomita “Solids concentration profiles and pressure drop in pipeline flow of multisized particulate slurries.” International journal of multiphase flow vol. 28 no. 10 pp. 1697-1717 2002.
 K. Ohira K. Nakagomi and N. Takahashi “Pressure-drop reduction and heat-transfer deterioration of slush nitrogen in horizontal pipe flow.” Cryogenics vol. 51 no. 10 pp. 563-574 2011.
 Y. Jiang and P. Zhang “Numerical investigation of slush nitrogen flow in a horizontal pipe” Chemical engineering science pp. 169-180 May 2012.
 Y. Jiang and P. Zhang “Pressure drop and flow pattern of slush nitrogen in a horizontal pipe” AIChE journal vol. 59 no. 5 pp. 1762-1773 May 2013.
 R. Durand and E. Condolis Experimental investigation of the transport of solids in pipes Deuxieme Journée de lhydraulique Societé Hydrotechnique de France 1952.
 T. Li and S. Benyahia “Evaluation of wall boundary condition parameters for gas–solids fluidized bed simulations” AIChE Journal vol. 53 no. 10 pp. 3624-3632 2013.