Claim Missing Document
Check
Articles

Found 2 Documents
Search
Journal : METAL : Jurnal Sistem Mekanik dan Termal

Accuracy of Turbulent Closure Models in Calculation of Thrust of a Low Reynolds Number Airfoil Used as a Propeller Adek Tasri
METAL: Jurnal Sistem Mekanik dan Termal Vol 6, No 1 (2022): Jurnal Sistem Mekanik dan Termal (METAL)
Publisher : Department of Mechanical Engineering, Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (178.188 KB) | DOI: 10.25077/metal.6.1.38-42.2022

Abstract

Unlike in the case of high Reynolds number airfoil, selecting a turbulent closure model for the low Reynolds number airfoil is still a challenge. A turbulent model used for high Reynolds number airfoil is not necessarily suitable for low Reynolds number airfoil due to the presence of separation bubbles in the low Reynolds number airfoil. In this study, we used two simple turbulent models, Spalart-Allmaras and k- , in calculating thrust coefficient of low Reynolds number airfoil used as propeller to determine their accuracy. It was found that there was a significant discrepancy between the numerical calculation results by both the turbulent model and the experimental data.  The k-  was a little more accurate than Spalart-Allmaras turbulent closure model.
Numerical Calculation of Thermal Stress in Cement Rotary-kiln Foundation at an early age Adek Tasri
METAL: Jurnal Sistem Mekanik dan Termal Vol 5, No 2 (2021): Jurnal Sistem Mekanik dan Termal (METAL)
Publisher : Department of Mechanical Engineering, Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (535.388 KB) | DOI: 10.25077/metal.5.2.67-71.2021

Abstract

This article discusses the early-age thermal stress, caused by the hydration heat, of a rotary kiln concrete foundation. We measure the hydration heat using an adiabatic calorie meter and perform finite volume numerical calculations to obtain the temperature distribution and finite element calculation to determine the thermal stress. The numerical simulation showed significant temperature differences between the core region and surface of the concrete. Compressive stress developed at the core, and tensile stress developed at the surface of the concrete during a heating period. The compressive stress was lower than the concrete compressive strength. The tensile stress was higher than the concrete tensile strength. So that crack developed in the surface. Heat treatment such as post-cooling or pre-cooling was needed to avoid the crack.