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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Dimensional analysis used to derive general equation for predicting gas pressurization requirements in cylindrical and spherical liquid propellant tanks
Mathematical procedures for correlating physical data obtained on various sized equipment to establish general physical laws or equations
Computer program for dimensional analysis using FORTRAN 4 programming
Dimensional analysis techniques are described and applied to the containment/deflection problem of bursting high-rpm rotating parts of turbojet engines. The use of dimensional analysis to select a feasible set of experiments and to determine the important parameters to be varied is presented. The determination of a containment coefficient based on the nondimensionalized parameters is developed for the reduction of experimental data and as an assist to designers of containment/deflection devices.
Dimensional analysis and synthesis by topological techniques, utilizing flow graphs to describe dimensional relationships between variables
Prediction of propellant tank pressurization requirements by dimensional analysis
Three-dimensional analysis of inducer fluid flow
Atrial and ventricular dimensional analysis in animals and man, discussing angiocardiographic, biplane, X ray, indicator dilution, radioisotopic and noninvasive methods
Variations in specific heat ratio, flow angle, critical velocity ratio, swirl distribution exponent, and radius ratio were considered in computing the mass flow. Variations in specific heat ratio had no significant effect and variations in critical velocity ratio had only small effect on computed mass flow between a one- and two-dimensional analysis. All non-free-vortex cases considered showed larger differences in computed mass flow between one- and two-dimensional analysis than for free vortex flow. For the non-free-vortex cases, decreasing radius ratio and increasing flow angle resulted in larger differences in mass flow as computed by the two methods.
Three dimensional analysis for determining effects of heat generation in plates
Dimensional analysis for interplanetary gas motion during solar flares
Dimensional analysis and group theory methods of solving ordinary and partial differential equations
Empirical correlation of small hollow sphere impact failure data using dimensional analysis
Electrolytic tank analog for two-dimensional analysis of electrostatic thrustor ion optics
One dimensional analysis of hypervelocity impact of pellet onto thin bumper using finite difference techniques
Three dimensional analysis and measurement of flow in three bladed pump inducer for liquid rocket engine
In the current analysis, we study the separation performance using membrane modules through dimensional analysis (DA). We formulate the main process equations to identify relevant dimensionless numbers inherent in the physics. In particular, we identify that the critical step in the separation process is mass transfer through the selective layer. Remarkably, the dimensionless feed flow (DFfeed) emerges as a crucial factor in describing this process. Not only does DFfeed directly appear in the governing equations, but it also holds a physical significance associated with the time scales for the mass transfer across the feed side and through the selective layer. Regarding the output performance variables, we consider the recovery, stage cut, productivity and purity. In this context, we profit from experimental data and CFD simulations to evaluate the separation performance of the modules when varying the input flowrate, the scale of the module, and the CO2 permeance. These datasets enable us to establish correlations between performance metrics and the dimensionless feed flow. Using simple power functions of DFfeed, we obtain R2 coefficients exceeding 0.99, indicating the accuracy of the correlations built in the present work. In the future, we wish to use DA to understand key transport mechanisms, predict and control module performance, and challenge the universality of these findings by testing various gas separations across different membrane modules beyond our case study.
Three-dimensional analysis of tangential yo-yo despin device on rotating rigid body