Engineering topics

Pond, J. E.

Publications and source records attributed to Pond, J. E..

6 records

NASA NTRS1992

Analytical flow/thermal modeling of combustion gas flows in Redesigned Solid Rocket Motor test joints

A one-dimensional analytical tool, TOPAZ (Transient One-dimensional Pipe flow AnalyZer), was used to model the flow characteristics of hot combustion gases through Redesigned Solid Rocket Motor (RSRM) joints and to compute the resultant material surface temperatures and o-ring seal erosion of the joints. The capabilities of the analytical tool were validated with test data during the Seventy Pound Charge (SPC) motor test program. The predicted RSRM joint thermal response to ignition transients was compared with test data for full-scale motor tests. The one-dimensional analyzer is found to be an effective tool for simulating combustion gas flows in RSRM joints and for predicting flow and thermal properties.

Woods, G. H.↗

NASA NTRS1983

MINIVER upgrade for the AVID system. Volume 3: EXITS user's and input guide

The successful design of thermal protection systems for vehicles operating in atmosphere and near-space environments requires accurate analyses of heating rate and temperature histories encountered along a trajectory. For preliminary design calculations, however, the requirement for accuracy must be tempered by the need for speed and versatility in computational tools used to determine thermal environments and structural thermal response. The MINIVER program was found to provide the proper balance between versatility, speed and accuracy for an aerothermal prediction tool. The advancement in computer aided design concepts at Langley Research Center (LaRC) in the past few years has made it desirable to incorporate the MINIVER program into the LaRC Advanced Vehicle Integrated Design, AVID, system. In order to effectively incorporate MINIVER into the AVID system, several changes to MINIVER were made. The thermal conduction options in MINIVER were removed and a new Explicit Interactive Thermal Structures (EXITS) code was developed. Many upgrades to the MINIVER code were made and a new Langley version of MINIVER called LANMIN was created.

Pond, J. E.↗

NASA NTRS1977

Analytical support for SPAR experiment 76-36

The apparatus, materials, and procedures used in an analysis of thermal, convective, and rotational fluid flow for a second series of rocket experiments of dendrite growth are described. A constitutive supercooling criterion was calculated from the thermal data. A convection analysis was made of the various cases to ensure that convective velocities will not exceed about .01 cm/sec in the low-g tests. Damping times for fluid flow generated by rocket spin-up and spin-down were also determined, so that the conditions for this experiment are generally the same as those for the SPAR experiment 74-21 study of ammonium chloride low-g crystallizations.

Bourgeois, S. V.↗

NASA NTRS1976

Thermal and convection analyses of the dendrite remelting rocket experiment; Experiment 74-21 in the space processing rocket program

The Dendrite Remelting Rocket Experiment was performed aboard a Black Brant VC Sounding Rocket during a period which gravity levels of approximately 0.00001 g prevailed. The experiment consisted of cooling an aqueous ammonium chloride solution in a manner such that crystallization of ammonium chloride crystals proceeded throughout a three minute period of zero-g. The crystallization process during flight was recorded on 35 mm panatomic-x film. A number of ground crystallizations were similarly recorded for comparison purposes. The convective and thermal conditions in aqueous and metallic liquid systems were assessed under conditions of the flight experiment to help establish the relevance of the rocket experiment to metals casting phenomena. The results indicate that aqueous or metallic convective velocities in the Dendrite Remelting Rocket Experiment cell are of insignificant magnitudes at the 0.0001 to 0.00001 g levels of the experiment. The crystallization phenomena observed in the Rocket Experiment, therefore, may be indicative of how metals will solidify in low-g.

Grodzka, P. G.↗

NASA NTRS1971

Shuttle reentry aerodynamic heating test

The research for determining the space shuttle aerothermal environment is reported. Brief summaries of the low Reynolds number windward side heating test, and the base and leeward heating and high Reynolds number heating test are included. Also discussed are streamline divergence and the resulting effect on aerodynamic heating, and a thermal analyzer program that is used in the Thermal Environment Optimization Program.

Pond, J. E.↗

NASA NTRS1969

Determination of quadric equation coefficients describing three-dimensional surfaces, their constraint and skewed planes, and view point areas

Mathematical model and a digital computer BLITZ language programming technique computes coefficients of quadric equations describing cylinders, paraboloids, ellipsoids, or planes with any orientation to a reference system, coordinates of a vector, and coefficients of quadric surfaces which limit the surface of three-dimensional space.

Paoletti, C. J.↗