In this paper, we propose a highly non-linear mathematical expression for characterising the flow behaviour of partially dense P/M materials during the case of simple upsetting – compression test, taking functional dependence of strain hardening index on a matrix strain and yield matrix (of partially dense material) on a mixed combination of matrix strain and strain sensitivity into account. Equivalent flow stress of matrix is considered to be a function of relative density, matrix strain and strain rate sensitivity parameters. A new parallel Runge-Kutta-fifth order algorithm with adaptive step-size control has been proposed for numerical integration of the resultant mathematical expression to compute the value of yield stress of partially dense P/M porous materials. Furthermore, a modest effort has been made to bring out the effectiveness of the adaptive step-size control. Numerical results show that the proposed parallel Runge-Kutta-fifth order algorithm with the adaptive step-size control increases the computational speed by more than eight times in an interval when solving the highly non-linear prevailing equation in comparison with the above algorithm with the fixed constant step-size.
- Inderscience Publishers
- New generalised plasticity equation for compressible powder ...
Curtailing Contamination Hydrocarbon Engineering July 2017
During planned shutdowns, the equipment in refineries and petrochemical plants has to be checked. The downtime can require several weeks when tanks, vessels, distillation columns, and pipes have to be drained and cleaned for i maintenance or repair. Shutdowns are labour-intensive and require accurate scheduling and organisation between all projects, as often hundreds of workers are on-site. A variety of materials such as greases, tars, ratty oils, polymers, or coke and iron sulfide deposits have to be removed....
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