Benchmark fluid flow problems for continuous simulation languages

✍ Scribed by S. Thompson; P.G. Tuttle

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 351 KB
• Volume: 12
• Category: Article
• ISSN: 0898-1221
• DOI: 10.1016/0898-1221(86)90193-8

✦ Synopsis

Two benchmark problems for continuous simulation languages are discussed. The use of the Advanced Continuous Simulation Language (ACSL) and the sparse ordinary differential equation solver DSTPGT, which has been incorporated into ACSL, are discussed for the solution of these fluid flow problems. The one-dimensional incompressible Navier-Stokes partial differential equations are discretized spatially using the method of pseudo-characteristics. The resulting sparse system of ordinary differential equations is then solved using the method of lines. A continuous-space-discrete-time solution is also given in order to illustrate the use of the DSTPGT special event detection mechanism (rootfinding) in ACSL. The discussions illustrate several important considerations related to the solution of complex fluid problems or, more generally, to sparse systems and/or systems requiring the detection and processing of special events. NOTATION p Density (kg/m3). G Flow rate (kg/m z s). T Temperature (*C). K Frictional pressure drop coefficient = 10.0. g, Gravitational acceleration = 9.80665 (m/s2). O 90*. el) Heat flux = I.IE5 (w/mZ). Ps Heated perimeter = 7.97318E+2 (m). A I Flow area ffi 3.82760 (m2). L 1.0 (m). T Absolute temperature = T + 273.15 (*K). p Pressure [MPa (10 e Pa)l. v Specific volume (m3/kg). h Specific enthalpy (kJ/kg). s Specific entropy (KJ/Kg-K). C; t Reciprocal of constant pressure specific heat (kg-K/ld). K -* Reciprocal of isothermal compressibility [MPa (106 Pa)]. 13 -t Reciprocal of coefficient volume expansion (K).

a Sound speed (m/s).