Fluid–structure interaction investigation for coal-water slurry preheaters: Effects of different loads on mechanical performance

The mechanical performance caused by fluid pressure or uneven temperature in heat exchangers is important to predict dangerous locations and guide the manufacture or installation. Under the background of coal-water slurry (CWS) preheating technology, using fluid–structure interaction, the distribution law, and mechanism of von Mises stress and deformation for CWS preheaters under different loads were studied, and sensitivity analysis combining metamodel of prognosis was carried out to determine the most influential parameters on mechanical performance. The results illustrate maximum von Mises stress under coupled pressure and temperature occurs at the perforated location on the baffle closed to the shell outlet, but maximum total deformation is located at the outer edge of the baffle near the shell inlet. When the folding angle, folding ratio, relative height is 30°, 0.4, and 0.5, respectively, under coupled loads, the thermal stress is dominant at lower velocity, and total deformation caused by the pressure is dominant at all different shell-inlet velocities. With increasing shell-inlet velocity, maximum von Mises stress decreases first and then increases, and maximum total deformation increases. The shell-inlet velocity and relative height are the most influential and non-influential parameters, respectively, for maximum total deformation. The research lays the foundation of mechanical analysis for material failure, structure destruction, and parameter screening of design variables for CWS preheaters.