36 research outputs found

    The SRB nozzle erosion related flow analysis

    Get PDF
    A study was performed to define the solid rocket booster (SRB) nozzle throat flow field, and to investigate one possible mechanism for the severe erosion which occurred on a recent flight. The flow field in the vicinity of the eroded area was not found to be exceptional, and the presence of a notch or scored area near the imbedded region nose did not appear to produce sufficient flow fluctuations to exacerbate the erosion characteristics of the throat liner. An interesting fluctuating mechanism was found in the imbedded cavity, but that mechanism (while of possible importance for erosion of the seal region) did not seem to adversely affect the region of concern. On the basis of this analysis, the conclusion can be drawn that the anomalous erosion did not result from a single mechanical defect (pit, or gouge) since the flow fluctuations which result seem insufficient to induce a repetitive pattern downstream. It further appears that the emission pattern exhibited did not result from a steady flow phenomena in the throat region. This does not rule out acoustic phenomena or severe start-up transients

    A variational principle for compressible fluid mechanics: Discussion of the multi-dimensional theory

    Get PDF
    The variational principle for compressible fluid mechanics previously introduced is extended to two dimensional flow. The analysis is stable, exactly conservative, adaptable to coarse or fine grids, and very fast. Solutions for two dimensional problems are included. The excellent behavior and results lend further credence to the variational concept and its applicability to the numerical analysis of complex flow fields

    An investigation of equilibrium concepts

    Get PDF
    A different approach to modeling of the thermochemistry of rocket engine combustion phenomena is presented. The methodology described is based on the hypothesis of a new variational principle applicable to compressible fluid mechanics. This hypothesis is extended to treat the thermochemical behavior of a reacting (equilibrium) gas in an open system

    A variational principle for compressible fluid mechanics. Discussion of the one-dimensional theory

    Get PDF
    The second law of thermodynamics is used as a variational statement to derive a numerical procedure to satisfy the governing equations of motion. The procedure, based on numerical experimentation, appears to be stable provided the CFL condition is satisfied. This stability is manifested no matter how severe the gradients (compression or expansion) are in the flow field. For reasons of simplicity only one dimensional inviscid compressible unsteady flow is discussed here; however, the concepts and techniques are not restricted to one dimension nor are they restricted to inviscid non-reacting flow. The solution here is explicit in time. Further study is required to determine the impact of the variational principle on implicit algorithms

    Prediction of electron density in rocket exhaust plumes

    Get PDF
    Analytical methods of predicting electron density in rocket exhaust plumes based on detailed descriptions of flow regimes and chemical model

    Analysis of the trajectory, loads and heating experienced by a body passing through a supersonic flow field

    Get PDF
    Analytical methods for determination of trajectories, loads, and heating experienced by spacecraft passing through rocket exhaust fiel

    Transonic flow in a converging-diverging nozzle Final report

    Get PDF
    Computerized solutions to finite difference equations of motion of transonic flow in converging-diverging rocket nozzle

    Microcomputer numerical analysis system for gas dynamics application

    Get PDF
    The original objective (scope) of the effort was to deliver a microcomputer version of the Continuum gas dynamic numerical analysis on existing NASA equipment. It became apparent during the course of the contract that the interests of NASA would be much better served by the delivery of a dedicated system designed and developed by Continuum, which would provide NASA with additional hardware ideally suited to the specific task at no increase in cost. Accordingly, the contract was modified to reflect this new development. The details of the modification and the delivered capability will be discussed in greater detail in the ensuing technical discussion

    Study of high altitude plume impingement

    Get PDF
    Computer program has been developed as analytical tool to predict severity of effects of exhaust of rocket engines on adjacent spacecraft surfaces. Program computes forces, moments, pressures, and heating rates on surfaces immersed in or subjected to exhaust plume environments. Predictions will be useful in design of systems where such problems are anticipated

    Space shuttle vehicle rocket plume impingement study for separation analysis Final report

    Get PDF
    Space shuttle vehicle rocket plume impingement study for separation analyse
    corecore