Author(s): Amjed Ahmed Jasim

Abstract: This study proposes a computational framework to address the uncertainties and evaluates the reliability of the computational predictions of the thermal-hydraulic design, between different models, for perforated helical twisted-tape (P-HTT) inserts. The contribution is methodological – it is not a new insert geometry, CFD dataset or conventional deterministic optimization, but rather, an experimentally validated empirical model is treated as an engineering prediction model and model behavior on the domain boundaries, uncertainty-conditioned model performance, convergence of the model numerical solution, and model transferability are tested. The audited P-HTT model is evaluated over Re = 6000–20000, d/w = 0.2–0.6, and s/w = 1–2. The outcome of the boundary analysis indicates that the nominal maximum is found at ? ? 1.283, Re = 6000, d/w = 0.20 and s/w = 2.0 which is a domain constrained optimum. A discrete search and a continuous search are compared and it is found that there is no contradiction with the optimum value of interpolation. Moreover, the numerical stability of the Monte Carlo method, with a Monte Carlo sample size ranging from 103 to 2.5 × 105, is demonstrated, with the value of the reference uncertainty ?5% remaining at around 1.248 over the clearly defined reference uncertainty scenario. Logarithmic-elasticity analysis analysis showed that the models have approximately 3.84× and 7.38× different effect size when using an independent correlation with the perforated twisted-tape under Reynolds number and perforation diameter respectively conditions, while the direction of the effect of both these variables can be transferred from one model to the other. Additionally, the analysis can be separated into the trends which are common to both tested models and the sensitivities which are related to the model structure to allow a meaningful interpretation of the optimal values ??of the thermo-hydraulic performance under conditions of uncertainty.

DOI: https://www.doi.org/10.22271/27078043.2026.v7.i2b.142

Pages: 104-109 | Views: 79 | Downloads: 39

Download Full Article: Click Here