Spartan Release Engagement Mechanism (REM) stress and fracture analysis

The revised stress and fracture analysis of the Spartan REM hardware for current load conditions and mass properties is presented. The stress analysis was performed using a NASTRAN math model of the Spartan REM adapter, base, and payload. Appendix A contains the material properties, loads, and stress analysis of the hardware. The computer output and model description are in Appendix B. Factors of safety used in the stress analysis were 1.4 on tested items and 2.0 on all other items. Fracture analysis of the items considered fracture critical was accomplished using the MSFC Crack Growth Analysis code. Loads and stresses were obtaind from the stress analysis. The fracture analysis notes are located in Appendix A and the computer output in Appendix B. All items analyzed met design and fracture criteria

Materials properties, loads, and stress analysis, Spartan REM: Appendix A

The mechanical properties, load tests, and stress analysis of the Spartan Release Engagement Mechanism (REM) is presented. The fracture properties of the components of the unit are also discussed. Detailed engineering drawings are included

The SPAR thermal analyzer: Present and future

The SPAR thermal analyzer, a system of finite-element processors for performing steady-state and transient thermal analyses, is described. The processors communicate with each other through the SPAR random access data base. As each processor is executed, all pertinent source data is extracted from the data base and results are stored in the data base. Steady state temperature distributions are determined by a direct solution method for linear problems and a modified Newton-Raphson method for nonlinear problems. An explicit and several implicit methods are available for the solution of transient heat transfer problems. Finite element plotting capability is available for model checkout and verification

SPAR thermal analysis processors reference manual, system level 16. Volume 1: Program executive. Volume 2: Theory. Volume 3: Demonstration problems. Volume 4: Experimental thermal element capability. Volume 5: Programmer reference

User instructions are given for performing linear and nonlinear steady state and transient thermal analyses with SPAR thermal analysis processors TGEO, SSTA, and TRTA. It is assumed that the user is familiar with basic SPAR operations and basic heat transfer theory

Elasticity and internal friction through the kilocycle range: reviwe and annotated bibliography

A review of techniques and fundamentals of Young\u27s modulus and internal friction measurements is presented. The effect of porosity on elasticity is extensively reviewed as are factors contributing to internal friction. An annotated bibliography of 377 entries covering elasticity and internal friction measurements through the kilocycle frequency range is included and accompanied by a keyword index

Computer models and output, Spartan REM: Appendix B

A computer model of the Spartan Release Engagement Mechanism (REM) is presented in a series of numerical charts and engineering drawings. A crack growth analysis code is used to predict the fracture mechanics of critical components

Performance, Stability, and Control Investigation at Mach Numbers from 0.60 to 1.05 of a Model of the "Swallow" with Outer Wing Panels Swept 75 degree with and without Power Simulations

An investigation of the performance, stability, and control characteristics of a variable-sweep arrow-wing model with the outer wing panels swept 75 deg. has been conducted in the Langley 16-foot transonic tunnel. Four outboard engines located above and below the wing provided propulsive thrust, and, by deflecting in the pitch direction and rotating in the lateral plane, also produced control forces. The engine nacelles incorporated swept lateral and vertical fins for aerodynamic stability and control. Jet-off data were obtained with flow-through nacelles, simulating inlet flow; jet thrust and hot-jet interference effects were obtained with faired-nose nacelles housing hydrogen peroxide gas generators. Six-component force and moment data were obtained at Mach numbers from 0.60 to 1.05 through a range of angles of attack and angles of side-slip. Control characteristics were obtained by deflecting the nacelle-fin combinations as elevators, rudders, and ailerons at several fixed angles for each control. The results indicate that the basic wing-body configuration becomes neutrally stable or unstable at a lift coefficient of 0.15; addition of nacelles with fins delayed instability to a lift coefficient of 0.30. Addition of nacelles to the wing-body configuration increased minimum drag from 0.0058 to 0.0100 at a Mach number of 0.60 and from 0.0080 to 0.0190 at a Mach number of 1.05 with corresponding reductions in maximum lift-drag ratio of 12 percent and 33 percent, respectively. The nacelle-fin combinations were ineffective as longitudinal controls but were adequate as directional and lateral controls. The model with nacelles and fins was directionally and laterally stable; the stability generally increased with increasing lift. Jet interference effects on stability and control characteristics were small but the adverse effects on drag were greater than would be expected for isolated nacelles

Development of low-cost feeds for fattening of native catfish, Clarias macrocephalus

Growth performance, survival, and feed efficiency in native catfish, Clarias microcephalus, fed chicken entrails, earthworm meal, and low-value fish meal were investigated. A simple cost-benefit analysis using this fattening approach was done to evaluate the profitability of using these low-value feed ingredients. Nine 30L aquaria were stocked with native catfish juveniles (about 20 cm in total length and 80 g in weight) at a density of 1 fish per liter. The catfish were fed cooked chicken entrails (Treatment 1), earthworm meal (Treatment 2) and low-value fish meal (Treatment 3) at 3% body weight for 60 days. At the end of the feeding trial, the growth of the fish fed various low-cost feeds was not significantly different. Survival was better in fish fed cooked chicken entrails than with either earthworm meal or low-value fish meal. Feed conversion efficiency (FCE) was relatively similar among the three types of feeds. A simple cost-benefit analysis using these low-cost feeds showed a return of investment (ROI) of 68-79%, indicating the feasibility of using these feeds for fattening of catfish. These preliminary results show that utilizing low value feed ingredients or food wastes as sources of feeds during fattening of native catfish are feasible. In addition, food wastage is reduced by bringing these food sources back to the food chain during aquaculture operations