Energikonsumtion hos en diskmaskin
The dishwasher is a wide spread product that occurs in many households. It saves the user time,water and energy. When using a dishwasher instead of doing dishes by hand a lot of energy issaved.The importance of lowering the energy consumption does not only come from the consumerwinnings but also from an environmental point of view. Scientists are certain that the globalwarming comes from the emission of green house gasses that is created by human consumptionof oil, gas and coal.Dishwashers today are a lot more energy efficient than older dishwashers, but there are stillmargins to lower the energy consumption. The aim with this project is to investigate thedishwasher and it?s washing cycle, noting different phases and components that contribute towaste of energy. Among these areas the most beneficial should be investigated further andsolutions on how to lover the energy consumption should be made.The most promising way to lower the energy consumption was found out to be the usage of acontra flow tube heat exchanger. The heat exchange should occur twice, first between the mainwash and the cold rinse and later between the cold rinse and the hot rinse. This stops cold waterfrom entering the tub of the dishwasher cooling down its interior and dishware.The channels of the heat exchanger were dimensioned to get the highest possible temperatureefficiency. The final channels are rectangular with the dimensions 0,03×0,005 m and the length0,34 m. With 80 channels the heat exchanger gets a temperature efficiency of 0,95. Due to thatthe heat exchange occurs twice with the same heat the efficiency is lowered to 0,90.With a temperature efficiency of 0,90 the total energy consumption of the heater can be loweredby 18%. That means that the declared value of the energy consumption could be lowered from1,05 kWh to 0,86 kWh.