Frontal algorithms for equation-based chemical process flowsheeting on vector and parallel computers

We present several frontal algorithms for solving the large, sparse, linear equation systems arising in equation-based (EB) chemical process flowsheeting. The frontal approach is generally used as a banded matrix solver in connection with finite element problems. We adapt it here to the more general process flowsheeting matrix. The motivation is that the frontal approach exploits vector computer architectures by treating parts of the sparse flowsheeting matrix as full submatrices, thereby allowing arithmetic operations to be performed with full-matrix code (without indirect addressing). On parallel computers, the inner loops of the elimination phase can be multitasked by simply subdividing the frontal matrix. Flowsheeting results show that the frontal approach performs very well on the CRAY X-MP/416 architecture. However, several pivot steps have to be overlapped on the CRAY-2 computer to ensure that both vector floating-point pipes are kept busy. Results concerning the use of multiple pivot steps indicate that two new assembly-language kernels designed for the CRAY-2 computer prove to be very efficient for performing rank-two and rank-four updates. In fact, the multitasked implementations of these kernels can achieve computational rates well over 1 Gigaflop when used as the nucleus of a frontal solver for EB flowsheeting. Overall, the frontal codes perform very well in comparison to the general sparse code, LU1SOL, and shows considerable promise for the solution of EB flowsheeting matrices on supercomputers.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical and Biomolecular Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Zitney, Stephen Edward

Contributors dc:contributor

• Stadtherr, Mark A.

• Mathematics
• Engineering, Chemical
• Computer Science

Statement dc:rights

• Copyright 1989 Zitney, Stephen Edward

Language dc:language

eng

Identifier

AAI9011090
(UMI)AAI9011090

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/22716