Engineering topics

Reardon, John E.

Publications and source records attributed to Reardon, John E..

7 records

NASA NTRS1993

Rocket plume base heating methodology

A review of radiative transport calculation methods for base heating is presented followed by a description of the current methodology for the Space Shuttle plume radiation predictions and improvements for the Advanced Solid Rocket Booster (ASRB). The calculation methods include empirical methods, the SIRRM code and the forward and reverse Monte Carlo methods. Current plume radiation methods include those used for the Space Shuttle Main Engines and the Solid Rocket Booster (SRB). Methods being developed for the ASRB include changes in plume property prediction methodology and application of the reverse Monte Carlo method in predicting plume radiation models. Results of the prediction methods are compared with experimental measurements on the current SRB and on 1/6-scale motors using both SRB and ASRB propellants. Examples are also presented demonstrating the statistical results available with the reverse Monte Carlo method.

Reardon, John E.↗

NASA NTRS1992

Base heating methodology improvements, volume 1

This document is the final report for NASA MSFC Contract NAS8-38141. The contracted effort had the broad objective of improving the launch vehicles ascent base heating methodology to improve and simplify the determination of that environment for Advanced Launch System (ALS) concepts. It was pursued as an Advanced Development Plan (ADP) for the Joint DoD/NASA ALS program office with project management assigned to NASA/MSFC. The original study was to be completed in 26 months beginning Sep. 1989. Because of several program changes and emphasis on evolving launch vehicle concepts, the period of performance was extended to the current completion date of Nov. 1992. A computer code incorporating the methodology improvements into a quick prediction tool was developed and is operational for basic configuration and propulsion concepts. The code and its users guide are also provided as part of the contract documentation. Background information describing the specific objectives, limitations, and goals of the contract is summarized. A brief chronology of the ALS/NLS program history is also presented to provide the reader with an overview of the many variables influencing the development of the code over the past three years.

Bender, Robert L.↗

NASA NTRS1992

User's manual for the ALS base heating prediction code, volume 2

The Advanced Launch System (ALS) Base Heating Prediction Code is based on a generalization of first principles in the prediction of plume induced base convective heating and plume radiation. It should be considered to be an approximate method for evaluating trends as a function of configuration variables because the processes being modeled are too complex to allow an accurate generalization. The convective methodology is based upon generalizing trends from four nozzle configurations, so an extension to use the code with strap-on boosters, multiple nozzle sizes, and variations in the propellants and chamber pressure histories cannot be precisely treated. The plume radiation is more amenable to precise computer prediction, but simplified assumptions are required to model the various aspects of the candidate configurations. Perhaps the most difficult area to characterize is the variation of radiation with altitude. The theory in the radiation predictions is described in more detail. This report is intended to familiarize a user with the interface operation and options, to summarize the limitations and restrictions of the code, and to provide information to assist in installing the code.

Reardon, John E.↗

NASA NTRS1992

NLS cycle 1 and NLS 2 base heating technical notes. Appendix 3: Preliminary cycle 1 NLS base heating environments. Cycle 1 NLS base heating environments. NLS 2 650K STME base heating environments

A preliminary analysis of National Launch System ascent plume induced base heating environments has been completed to support the Induced Environments Panel's objective to assist in maturing the NLS vehicle (1.5 stage and heavy launch lift vehicle) design. Environments during ascent have been determined from this analysis for a few selected locations on the engine nozzles and base heat shield for both vehicles. The environments reflect early summer 1991 configurations and performance data and conservative methodology. A more complete and thorough analysis is under way to update these environments for the cycle 1 review in January 1992.

Bender, Robert L.↗

NASA NTRS1991

Aero/fluids database system

The AFAS Database System was developed to provide the basic structure of a comprehensive database system for the Marshall Space Flight Center (MSFC) Structures and Dynamics Laboratory Aerophysics Division. The system is intended to handle all of the Aerophysics Division Test Facilities as well as data from other sources. The system was written for the DEC VAX family of computers in FORTRAN-77 and utilizes the VMS indexed file system and screen management routines. Various aspects of the system are covered, including a description of the user interface, lists of all code structure elements, descriptions of the file structures, a description of the security system operation, a detailed description of the data retrieval tasks, a description of the session log, and a description of the archival system.

Reardon, John E.↗

NASA NTRS1989

Preliminary base heating environments for a generalized ALS LO2/LH2 launch vehicle, appendix 1 and 2

A secondary objective of contract NAS8-39141 is to provide base heating assessments, as required, to support Advanced Launch System (ALS) preliminary launch vehicle and propulsion system design studies. The ALS propulsion systems integration working group meeting (No. 3) recently completed in San Diego, California, focused attention on the need for base heating environment determination to provide preliminary requirements for LO2/LH2 propulsion systems currently being considered for ALS. We were requested to provide these environments for a range of possible propellant mixture and nozzle area ratios. Base heating environments can only be determined as a function of altitude when the engine operating conditions and vehicle base region geometry (engine arrangement) are known. If time dependent environments are needed to assess thermal loads, a trajectory must also be provided. These parameters are not fixed at this time since the ALS configurations and propulsion operating conditions are varied and continue to be studied by Phase B contractors. Therefore, for this study, a generalized LO2/LH2 system was selected along with a vehicle configuration consisting of a seven-engine booster and a three-engine core. MSFC provided guidance for the selection. We also selected a limited number of body points on the booster and core vehicles and engines for the environment estimates. Environments at these locations are representative of maximum heating conditions in the base region and are provided as a function of altitude only. Guidelines and assumptions for this assessment, methodology for determining the environments, and preliminary results are provided in this technical note. Refinements in the environments will be provided as the ALS design matures.

Bender, Robert L.↗

NASA NTRS1988

Development of a shuttle plume radiation heating indicator

The primary objectives were to develop a Base Heating Indicator Code and a new plume radiation code for the Space Shuttle. Additional work included: revision of the Space Shuttle plume radiation environment for changes in configuration and correction of errors, evaluation of radiation measurements to establish a plume radiation model for the SRB High Performance Motor (HPM) plume, radiation predictions for preliminary designs, and participation in hydrogen disposal analysis and testing for the VAFB Shuttle launch site. The two most significant accomplishments were the development of the Base Heating Indicator Code and the Shuttle Engine Plume Radiation (SEPRAD) Code. The major efforts in revising the current Shuttle plume radiation environment were for the Orbiter base heat shield and the ET components in the Orbiter-ET interface region. The work performed is summarized in the technical discussion section with references to the documents containing detailed results. The technical discussion is followed by a summary of conclusions and recommendations for future work.

Reardon, John E.↗