Andre Leclair | Engineering Papers

NASA NTRS2023

Analysis of Cryogenic Propellant Liquefaction Rates in Cooled Constant-Wall-TemperatureTanks

NASA has been focused on developing technology that would allow the production of cryogenic propellants on the Lunar and Martian surfaces. Utilizing Lunar/Martian resources, the produced gaseous propellants must first be liquefied and stored prior to use on the Moon or Mars ascent vehicle. Liquefaction of cryogenic propellant is a necessary technical development to enable NASA’s future spaceflight goals. This paper presents an overview of the effect of spacecraft propellant system parameters on cryogenic propellant liquefaction rates. The propellant system was assumed to be a receiver of a gas from an In-Situ Resource Utilization (ISRU) harvester and condensed the gas by cooling the tank walls. First, the general thermodynamic principles pertinent to condensation are summarized, followed by an overview of the model which performed the analysis, including a summary of the Fortran implementation. Comparisons between the model results and test data are discussed, as well as sensitivity of the condensation rate to various parameters.

cryogenics↗

NASA NTRSDate not supplied

Numerical Modeling of No Vent Filling of a Cryogenic Tank

This paper presents a multi-node finite volume model of the chilling and filling of a cryogenic tank using the Generalized Fluid System Simulation Program (GFSSP), a general purpose flow network code. Vented Chill and No Vent Fill (VCNVF) tests were conducted at Marshall Space Flight Center where a flight-like tank was filled with liquid nitrogen from a supply tank. In the VCNVF tests, the tank was partially chilled while the vent valve was open. After the partial chilling, the vent valve was closed and the tank was filled without any venting. An integrated numerical model of the test set up was developed. The model included the transfer line from the supply tank, the target tank with the spray nozzle and solid walls, and the discharge line with the vent valve. The tank was discretized into multiple fluid nodes and branches to represent the ullage and liquid nitrogen and multiple solid nodes to represent the tank wall and structure. The heat transfer between solid to fluid was calculated from pool boiling correlations which include film, transition, and nucleate boiling, as well as natural convection during pre- and post-boiling. The model also accounts for the condensation of vapor in the tank when it comes in contact with the liquid spray. The predicted pressure, resident mass, wall and ullage temperature in the tank were compared with the test data.

Alok Majumdar↗

NASA NTRSDate not supplied

GFSSP Software Demo

A one hour demonstration of the Generalized Fluid System Simulation Program.

Andre Leclair↗

NASA NTRSDate not supplied

Axisymmetric Two-Dimensional Modeling of No Vent Filling of a Cryogenic Tank using Generalized Fluid System Simulation Program

Filling a tank with cryogenic fluid is more challenging than filling a tank with water or any other fluid that is in liquid state at atmospheric condition. Filling a tank with cryogenic fluid is a two-step process. First the tank and the transfer line mustbe chilled. Liquid cryogens start flowing into the tank only after the tank and transfer lines are chilled to the fluid saturation temperature. In normal gravity, cryogenic tanks are usually filled from the bottom at nearly atmospheric pressure. The vapor, caused by heat transfer from the warm tank walls, is allowed to vent from the top of the tank while the tank is being filled. Filling a cryogenic tank in the absence of gravity is more challenging because in a non-stratified environment liquid propellantmay not settle at the tank bottom as it does on earth. There is a strong possibility that liquid propellant may exit through the vent valve, which is typically located at the top of the tank to vent propellant vapor. There are several methodsof filling atank in space: Charge-Hold-Vent method [1], Vented-Chill / No-Vent-Fill (VCNVF)[2],and No Vent Fill with TVS assisted injector [3].This paper addressesnumerical modelingofthe No Vent Fill (NVF) processwhere a TVS (Thermodynamic Vent System) augmented injector was used with the vent valve closed during the entire filling process. NVF tests were conducted in the CRYOgenic Orbital Testbed (CRYOTE) tankat NASA/Marshall Space Flight Centerin 2018.The Generalized Fluid System Simulation Program (GFSSP), a general-purpose flow network code [4] was used to simulate the chilland fill process.

Cryogenics↗

NASA NTRSDate not supplied

Analysis of Cryogenic Propellant Liquefaction Rates in Cooled Constant-Wall-Temperature Tanks

NASA has been focused on developing technology that would allow the production of cryogenic propellants on the Lunar and Martian surfaces. Utilizing Lunar/Martian resources, the produced gaseous propellants must first be liquefied and stored prior to use on the Moon or Mars ascent vehicle. Liquefaction of cryogenic propellant is a necessary technical development to enable NASA’s future spaceflight goals. This paper presents an overview of the effect of spacecraft propellant system parameters on cryogenic propellant liquefaction rates. The propellant system was assumed to be a receiver of a gas from an In-Situ Resource Utilization (ISRU) harvester and condensed the gas by cooling the tank walls. First, the general thermodynamic principles pertinent to condensation are summarized, followed by an overview of the model which performed the analysis, including a summary of the Fortran implementation. Comparisons between the model results and test data are discussed, as well as sensitivity of the condensation rate to various parameters.

Anson Koch↗

NASA NTRSDate not supplied

Analysis of Cryogenic Propellant Liquefaction Rates in Cooled Constant-Wall-Temperature Tanks

NASA has been focused on developing technology that would allow the production of cryogenic propellants on the Lunar and Martian surfaces. Utilizing Lunar/Martian resources, the produced gaseous propellants must first be liquefied and stored prior to use on the Moon or Mars ascent vehicle. Liquefaction of cryogenic propellants is a necessary technical development to enable NASA’s future spaceflight goals. This paper presents an overview of a proposed model for a propellant liquefaction system, and the effect of tank wall temperatures on cryogenic propellant liquefaction rates. The propellant system was assumed to be a receiver of a gas from an In-Situ Resource Utilization (ISRU) harvester and condensed the gas by cooling the tank walls. First, the heat transfer principles pertinent to condensation are summarized, followed by an overview of the model which performed the analysis, including a summary of the Fortran algorithm implementation. The sensitivity of the condensation rate relative to varying tank wall temperatures is also discussed.

Anson Koch↗

NASA NTRSDate not supplied

Analysis of Cryogenic Propellant Liquefaction Rates in Cooled Constant-Wall-TemperatureTanks

NASA has been focused on developing technology that would allow the production of cryogenic propellants on the Lunar and Martian surfaces. Utilizing Lunar/Martian resources, the produced gaseous propellants must first be liquefied and stored prior to use on the Moon or Mars ascent vehicle. Liquefaction of cryogenic propellants is a necessary technical development to enable NASA’s future spaceflight goals. This paper presents an overview of a proposed model for a propellant liquefaction system, and the effect of tank wall temperature and the ullage pressure control band on cryogenic propellant liquefaction rates. The propellant system was assumed to be a receiver of a gas from an In-Situ Resource Utilization (ISRU) harvester and condensed the gas by cooling the tank walls. First, the heat transfer principles pertinent to condensation are summarized, followed by an overview of the model which performed the analysis, including a summary of the Fortran algorithm implementation. The sensitivity of the condensation rate relative to varying tank wall temperatures is also discussed.

cryogenics↗

NASA NTRSDate not supplied

Analysis of Cryogenic Propellant Liquefaction Rates in Cooled Constant-Wall-Temperature Tanks

NASA has been focused on developing technology that would allow the production of cryogenic propellants on the Lunar and Martian surfaces. Utilizing Lunar/Martian resources, the produced gaseous propellants must first be liquefied and stored prior to use on the Moon or Mars ascent vehicle. Liquefaction of cryogenic propellant is a necessary technical development to enable NASA’s future spaceflight goals. This paper presents an overview of the effect of spacecraft propellant system parameters on cryogenic propellant liquefaction rates. The propellant system was assumed to be a receiver of a gas from an In-Situ Resource Utilization (ISRU) harvester and condensed the gas by cooling the tank walls. First, the general thermodynamic principles pertinent to condensation are summarized, followed by an overview of the model which performed the analysis, including a summary of the Fortran implementation. Comparisons between the model results and test data are discussed, as well as sensitivity of the condensation rate to various parameters.

cryogenics↗

NASA NTRSDate not supplied

Progress on the Reduced Gravity Cryogenic Transfer (RGCT) Project

Reduced gravity transfer of cryogenic propellants is crucial to being able to perform planned extended-duration space exploration missions. However, the transfer of cryogenic propellants under reduced gravity conditions has never been demonstrated in a mass-efficient fashion. Efficient cryogenic fluid transfer methods will reduce the transfer time or amount of propellant consumed for chilldown of transfer lines and tanks and ensure successful engine restart or fill of a customer receiver tank. The purpose of the Reduced Gravity Cryogenic Transfer (RGCT) project is to enhance line chilldown, tank chilldown, and tank fill/transfer in a reduced gravity environment through (1) ground and reduced gravity cryogenic testing and (2) numerical model development and validation, which includes empirical, lumped capacitance, and computational fluid dynamics modeling. Technologies developed, data gathered, and models developed and validated under RGCT have played a critical role in enabling longer duration in-space missions. This presentation will provide a description of the ongoing cryogenic propellant transfer ground and reduced gravity testing, numerical modeling, and technology development to-date.

Boiling↗

NASA NTRSDate not supplied

Nodal Modeling of Submerged Helium Injection Pressurization of a Cryogenic Propellant Tank

Subcooling of cryogenic propellant by helium injection is one of the most effective methods for suppressing bulk boiling and keeping subcooled propellant conditions for pre-launch, launch, and post-launch pressurization applications. For tank pressurization, submerged helium injection can substantially reduce helium consumption by infusing gaseous propellant into the tank ullage. This paper describes a thermodynamic model of the helium bubbling process in liquid oxygen to estimate the amount of oxygen vapor absorbed by the rising helium bubbles and the amount of subcooling of liquid oxygen due to evaporative heat and mass transfer. The physics of helium dissolution during the pressurization process is also modeled, primarily for liquid hydrogen propellant where the dissolution is more significant. The analyses were performed in a simulation model of tank pressurization built with Generalized Fluid System Simulation Program (GFSSP), a general-purpose flow network code developed at NASA/Marshall Space Flight Center. The numerical predictions of subcooling have been compared with the experimental data of Cho et al. which investigated the propellant subcooling effect as a function of system pressure, helium injection temperature, and flowrate for a non-drained submerged injection system. The numerical predictions of helium consumption have been compared with the test data from a NASA Centaur test vehicle which included both direct and submerged injection with draining of propellants. Hydrogen propellant testing of the Cryogenic Propellant Storage and Transfer Engineering Developmental Unit (CPST EDU) conducted at NASA/Glenn Research Facility was also analyzed. The data used for the model validation were taken in 1-g, but the model was developed to be applicable in both multi-g and micro-g environments.

tank pressurization↗