Abstract

Whirlpool Corporation designs and develops appliances which are intended for household and commercial purpose and Dishwasher is one such appliance. The Dishwashers are handled by consumers, children, or others who may be unskilled. Every time a consumer uses the dishwasher, they open the door to keep the utensils inside. This door is connected to the dishwasher tub with a door tab. The integrity of this door tab is important from the performance aspect of the door. The failure of the door tab may also lead to the safety hazard issue and hence it becomes important to provide a robust and reliable door tab. During door cycle testing which is cyclic in nature, failure of the tab is observed. The tab sustains for around 25% of the required door cycles (opening and closing of door). In order to understand the root causes of the failure and to identify significant factors, the simulation studies are carried out. The simulation methodology is developed to replicate the door cycle test. The door cycles are simulated in order to evaluate the bending stresses developed on the door tab during its real time application for one cycle. The fatigue life of the door tab is predicted using a uniaxial fatigue approach. This approach is utilized to correlate the simulation results with actual test data. There is a significant difference in the test and simulation results. To improve the correlation, a multi-axial fatigue approach is adopted in order to incorporate the non-proportional loading which is observed to be critical during door cycling operation. Using a multi-axial approach, good correlation is observed on the door tab failure cycles. To evaluate and improve the current design of the door tab, the root causes and factors are identified in simulation studies. Alternatively, the fatigue life was also evaluated using a commercial fatigue software and compared with the analytical outcomes. This paper also extends its scope on suggesting countermeasures to fix the issue and drive improvement to enhance the life and the reliability of the Dishwasher door tab.