An investigation of the information propagation and entropy transport aspects of Stirling-machine numerical simulation. Final Report

Technical Report · Wed Apr 01 00:00:00 EST 1992

OSTI ID:7030966

Goldberg, L F

Aspects of the information propagation modeling behavior of integral machine computer simulation programs are investigated in terms of a transmission line. In particular, the effects of pressure-linking and temporal integration algorithms on the amplitude ratio and phase angle predictions are compared against experimental and closed-form analytic data. It is concluded that the discretized, first order conservation balances may not be adequate for modeling information propagation effects at characteristic numbers less than about 24. An entropy transport equation suitable for generalized use in Stirling machine simulation is developed. The equation is evaluated by including it in a simulation of an incompressible oscillating flow apparatus designed to demonstrate the effect of flow oscillations on the enhancement of thermal diffusion. Numerical false diffusion is found to be a major factor inhibiting validation of the simulation predictions with experimental and closed-form analytic data. A generalized false diffusion correction algorithm is developed which allows the numerical results to match their analytic counterparts. Under these conditions, the simulation yields entropy predictions which satisfy Clausius' inequality.

• Research Organization: Minnesota Univ., Minneapolis, MN (United States)
• OSTI ID: 7030966
• Report Number(s): N-92-27975; NASA-CR-189143; NAS-1.26:189143; CNN: NASA ORDER C-22742-P; RTOP 590-13-11
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
STIRLING ENGINES
COMPUTERIZED SIMULATION
ALGORITHMS
ENTROPY
INCOMPRESSIBLE FLOW
INFORMATION THEORY
PHASE SHIFT
STIRLING CYCLE
THERMAL DIFFUSION
DIFFUSION
ENGINES
FLUID FLOW
HEAT ENGINES
MATHEMATICAL LOGIC
PHYSICAL PROPERTIES
SIMULATION
THERMODYNAMIC CYCLES
THERMODYNAMIC PROPERTIES
330201* - External Combustion Engines- Stirling Cycle