Wet dishes out of the dishwasher

[lisab]

When a dishwasher is finished with its cleaning/drying cycle, all the dishes in it are at the same temperature. But the glass and ceramic ones are dry, while the plastic ones have drops of water all over them.

Why? Is it a heat capacity difference, or is it a surface energy effect? Or...?

 

[Aero51]

My first guess would be location porosity and shape. I am at a bar right now can't help you with a heat xfer analysis :(

 

[chemisttree]

Ceramic ones cool more slowly than the plastic ones. They are at the same temperature for only a short time. The ceramic ones also shed water better since they have a higher surface energy than the 'greasy' poly.

 

[256bits]

Hi Lisab.
That is a very good question that you bring up on what to expect from your dishwasher. A perfectly functioning dishwasher can alleviate some of the drudgery of kitchens tasks after the meal is served and make your life more enjoyable knowing that it is doing the job it was supposed to do.
I did notice that you did not mention silverware. A check for drops of water are being left on some of the plates and cups and the eating utensils leads to a conclusion that the settings on the dishwasher may be leading to a degradation of performance and may require a reset. Before doing that though, as it involves intricate detail and perseverance, please do your own verification that you have pressed the right buttons. As most dishwashers do not come with a manual this may take some trial and error to get things right. Coaching the diswasher for correct procedure will help as it may have forgotten, or it may be taking shortcuts to complete the task so it can take a rest break sooner.

In any event, you may have become accustomed to your dishwasher and have grown so fond of it after all the years of service and being together that it part of the family. That is OK. Some shortcomings will have to be overlooked, but many have chosen this path instead of aquiring a brand new shinier model, which, like many products nowadays, do not have the reliabilitity and endurance and especially the cherished memorable moments of your keepsake model.

Some hints on how to get the best performane from your dishwasher:
1. Praise your dishwasher for a job well done ( even if not ), and it may begin to work harder and more efficient knowing that such a thankless task is being very much so appreciated.
2. contrarily, refrain from yelling at or berating your dishwasher as it may become disillusioned and depressed and that is not good for its interior working parts.
3. Give you dishwasher a much needed break sometimes and do the washing and drying yourself. Some pampering does wonders.
4. Act apologetic for any ardeous task the dishwasher may encounter such as dried on egg yolk or greasy food cleanup. The dishwasher will feel part of the solution and attack the problem with so much more vigor.

While specific to each household, the patron-dishwasher relationship can last years if nurtured, and after every meal the relaxation period can be most enjoyable for the both of you. After all, dishwashers are human too.

 

[LudusRex]

This is a common observation and can be explained by a combination of heat capacity and surface energy effects. The glass and ceramic dishes have a higher heat capacity, meaning they can absorb more heat energy before reaching the same temperature as the plastic dishes. This allows them to dry faster as they can dissipate the heat more quickly.

On the other hand, plastic has a lower surface energy compared to glass and ceramic. This means that water molecules are more likely to stick to the surface of plastic, forming droplets. This is due to the cohesive forces between the water molecules being stronger than the adhesive forces between the water and plastic surface.

Additionally, the shape and texture of the dishes can also play a role in the drying process. Glass and ceramic dishes often have smoother surfaces, allowing water to flow off more easily. Plastic dishes, on the other hand, may have more irregular surfaces, providing more places for water droplets to cling onto.

In conclusion, the difference in heat capacity and surface energy between glass/ceramic and plastic dishes contribute to the varying levels of dryness observed after a dishwasher cycle. Other factors such as dish shape and texture can also play a role.