Engineering topics

Moder, J. P.

Publications and source records attributed to Moder, J. P..

4 records

NASA NTRS2017

Tank System Integrated Model: A Cryogenic Tank Performance Prediction Program

Accurate predictions of the thermodynamic state of the cryogenic propellants, pressurization rate, and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning for future space exploration missions. This Technical Memorandum (TM) presents the analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, mixing, and condensation on the tank wall. This TM also includes comparisons of TankSIM program predictions with the test data andexamples of multiphase mission calculations.

Bolshinskiy, L. G.↗

NASA NTRS2015

TankSIM: A Cryogenic Tank Performance Prediction Program

Accurate prediction of the thermodynamic state of the cryogenic propellants in launch vehicle tanks is necessary for mission planning and successful execution. Cryogenic propellant storage and transfer in space environments requires that tank pressure be controlled. The pressure rise rate is determined by the complex interaction of external heat leak, fluid temperature stratification, and interfacial heat and mass transfer. If the required storage duration of a space mission is longer than the period in which the tank pressure reaches its allowable maximum, an appropriate pressure control method must be applied. Therefore, predictions of the pressurization rate and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning of future space exploration missions. This paper describes an analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. It is written in the FORTRAN 90 language and can be compiled with any Visual FORTRAN compiler. A thermodynamic vent system (TVS) is used to achieve tank pressure control. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, and mixing. Details of the TankSIM program and comparisons of its predictions with test data for liquid hydrogen and liquid methane will be presented in the final paper.

Bolshinskiy, L. G.↗

NASA NTRS2015

TankSIM: A Cryogenic Tank Performance Prediction Program

Developed for predicting the behavior of cryogenic liquids inside propellant tanks under various environmental and operating conditions. Provides a multi-node analysis of pressurization, ullage venting and thermodynamic venting systems (TVS) pressure control using axial jet or spray bar TVS. Allows user to combine several different phases for predicting the liquid behavior for the entire flight mission timeline or part of it. Is a NASA in-house code, based on FORTRAN 90-95 and Intel Visual FORTRAN compiler, but can be used on any other platform (Unix-Linux, Compaq Visual FORTRAN, etc.). The last Version 7, released on December 2014, included detailed User's Manual. Includes the use of several RefPROP subroutines for calculating fluid properties.

Bolshinskiy, L. G.↗

NASA NTRS1987

Laser-energized MHD generator for hypersonic electric air-turborockets

The analysis and design of an open cycle Faraday MHD generator suitable for use in an electric air-turborocket cycle, the MHD-fanjet, is presented. The working fluid for the generators is unseeded high temperature hydrogen, generated by a standing, laser-supported combustion wave. This study also examines the performance of an advanced combined-cycle engine, powered by beamed energy, proposed for use in future SSTO aerospacecraft. This innovative engine incorporates the MHD-fanjet for the acceleration role within the hypersonic flight regime, from about Mach 11 to above Mach 25. Performance results indicate that specific impulses could fall in the range of 10,000 to 16,000 seconds. This would enable propellant mass fractions as low as 6 percent to 9 percent for such advanced shuttlecraft flying SSTO missions to low earth orbit.

Myrabo, L. N.↗