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Noah Rhys

Publications and source records attributed to Noah Rhys.

Test data analysis of the thermodynamic vent system-augmented top spray injector liquid nitrogen transfer experiments

Traditionally, a cryogenic tank must be pre-chilled to some “target” temperature before the main vent valve can be closed to attempt a non-vented fill (NVF) of cryogenic liquid propellant. This methodology is particularly attractive for performing in-space transfer of cryogens due to the unknown location of the liquid/vapor interface in microgravity and the high likelihood of venting liquid if the vent valve is opened during transfer. This paper presents in-depth test data analysis of a Thermodynamic Vent System (TVS) augmented injector used for cryogenic tank chilldown and fill experiments of a thin-walled Titanium tank. Eight tests were conducted using liquid nitrogen across a range of inlet conditions and boundary conditions, and three different chilldown/fill methods. For four of the tests, the injector sprays liquid into the tank as normal, but also uses a TVS heat exchanger to cool the metallic injector itself as well as the main incoming liquid stream. Results show that using the TVS augmented injector simplifies transfer operation via enhanced condensation at the injector surface at the cost of sacrificing only a small amount of propellant.

No-vent Fill↗

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↗

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↗

Development of an Additive Manufactured Cryogenic TVS Augmented Injector

Cryogenic fluid transfer is critical in ground and space systems. Transfer typically requires venting a receiver vessel during the chill and fill process to maintain a pressure favorable to fluid flow. Venting in space is problematic due to low-gravity where fluid position is indeterminate; possibly allowing fluid to flow out the vent. To control receiver tank venting the vented chill/no-vent fill methodology is attractive. An additively manufactured Injector coupled with a Thermodynamic Venting System (TVS) augmentation can enable the vented chill/no-vent fill approach with simplified operations. The TVS augmented injector includes an internal heat exchanger, fluid injector spray head, and external surface condensation heat exchange; combined with integrated flow paths in one part. Operations using the injector allow the tank vent to be closed very early in the transfer and not reopened. The TVS circuit eliminates the potential for stalled fill by maintaining cooling flow on the injector and condenser elements, reducing tank pressure. The injector can also be employed for long-term cryo fluid storage as a means of controlling tank pressure if integrated with a recirculation pump. A cryo-cooler can be used in place of/or augmenting the TVS flow circuit for a zero loss pressure control system. The Injector was developed using the principles of design for additive manufacture and printed as one part, resulting in part count reduction, improved reproducibility, shorter lead times, and reduced cost. The TVS augmented injector is compact and highly adaptable simplifying its integration. A key benefit is that this methodology enables simplified operations in reaching 100% fill conditions.

Omar Mireles↗

Testing of TVS Augmented Injectors for Tank-to-Tank Transfer of Cryogens

NASA is developing reusable cryogenic systems to enable manned missions to the Moon and Mars. These cryogenic systems will require replenishing cryogens on-orbit via a tanker or propellant depot with minimal loss to boil-off. Three additively manufactured injectors augmented with a Thermodynamic Venting System have been developed for use in tank-to-tank cryogenic fluid transfer. A Vented Chill/No-Vent Fill approach to tank-to-tank transfer has been the industry standard and is explored in this work with emphasis on injector spray patterns and compared to the Charge-Hold-Vent chill method.

Cryogenic Transfer↗

Testing of TVS Augmented Injectors for Tank-to-Tank Transfer of Cryogens

NASA is developing reusable cryogenic systems to enable manned missions to the Moon and Mars. These cryogenic systems will require replenishing cryogens on-orbit via a tanker or propellant depot with minimal loss to boil-off. Three additively manufactured injectors augmented with a Thermodynamic Venting System have been developed for use in tank-to-tank cryogenic fluid transfer. A Vented Chill/No-Vent Fill approach to tank-to-tank transfer has been the industry standard and is explored in this work with emphasis on injector spray patterns and compared to the Charge-Hold-Vent chill method.

Cryogenic Transfer↗