An Investigation of the Effect of Coolants on Residual Stresses in Weldments Based on Entropy Generation

How to cool the weldments is the one of the important input parameters to control the welding process and achieve a safe design. Generally, several coolants can be used for this aim. However, air and water that have been studied in this paper not only have too many practical applications but also will be examined as representative coolants. Heat transfer analysis based on convection coefficients, is one of the best method to investigate the effect of these coolants on induced residual stresses behavior. To fulfill this, in the present work, entropy generation has been introduced as a tool to predict the distribution of residuals tresses qualitatively. To check the application of the proposed method, a 3D numerical model is employed to study the similar behavior of residual stresses and entropy generation due to variation of different Heat transfer coefficients. Furthermore, the effect of convection coefficients on residual stresses and entropy generation has been investigated for both free and forced convections. Based on the present method's results, one can find that the behavior of entropy generation and residual stresses distribution with respect to different convection coefficients are very similar. Finally, the application of entropy generation minimization is checked in looking for the range of a satisfactory design in welding.

Keywords:

Entropy generation , Residual stresses , Welding , Coolant , Convection coefficient