An Experimental Study of Surface Improvement in FDM Parts by Vapor Treatment Process

Fused deposition modeling (FDM) is one of the most adaptable additive manufacturing method owing to the cost-effectiveness and environment-friendly nature. However, FDM technique still possesses major difficulties in terms of poor surface quality because of adding layer by layer manufacturing process for the prototypes. It is desirable to explore an efficient technique for FDM parts to enhance the poor surface quality and dimensions precision. In the present paper, an effort has been made to enhance the surface quality and optimize the critical processing parameter of FDM based benchmark using vapor smoothing process (VSP). A comparative experimental study has been performed by design of experiments (DOE), Taguchi technique to find the influence of input design parameters on the surface finish of benchmark FDM parts. The results of the present investigation show that VSP treatment improves the surface quality of FDM parts to micro level with negligible dimensional variation. It is observed that improved surface quality is found in the 1,2, -Dichloroethane chemical at 90° part build orientation, 0.25 mm layer thickness, 10% fill density and 90 second exposure times

A case study of thermal mixing behavior of hot and cold fluid in T-junction with/without mixing jets

Three-dimensional numerical simulations are performed to study the turbulent mixing of hot and cold fluids at a T-junction with unique branch pipe extended mixing jets. The major aim of the current research is to compare the performance of two distinct designs for thermal mixing and flow characteristics of a T-junction. We investigate the effects of the momentum ratio and temperature difference of mixing fluids on temperature gradients for proposed configurations of T-junctions. The finding demonstrated that a T-junction with jets appears to mix hot and cold fluids more homogeneously. The addition of the mixing jets significantly lessens the internal wall's temperature gradients and improves the efficacy of thermal mixing. The thermal mixing efficiency for T-junctions with mixing jets increased by 25%, 42%, and 50%, respectively. At the same momentum ratio, the length of the thermal mixing in the T-junction with mixing jets is dramatically reduced by 77%, 79%, and 83%. The stress distribution is also determined using thermo-mechanical coupled analysis. The result shows the reduction in peak stresses substantially with the mixing jet T-junction. The current study will help the researcher to evaluate safety issues in high-temperature applications and better understand thermal mixing, flow characteristics, and thermal cracks