En studie med teoretisk modell och CFD-simuleringar av luftflödet i en värmepumpstorktumlare

Abstract: Drying clothes is an essential but energy demanding process in modern society. A common way to dry clothes is tumble drying. Electrolux is one of the world leading manufacturers of household appliances and currently is working on a heat pump tumble dryer product. This master thesis is a study of the aerodynamic properties for the internal air flow for the mentioned heat pump tumble dryer. If pressure losses can be reduced then the energy required for the fan can be lowered. The goal is to identify pressure distribution and potential geometry improvements across the system. The work consisted in building a prototype of a theoretical pressure distribution model, doing CFD simulations inside the heat pump side of the geometry, and one geometry change was tested in CFD and at the lab in Ljungby. The theoretical model was constructed with laundry load and filter clogging as inputs and pressure distribution as outputs. The model was useful in identifying critical values for load and filter in creating suction in the drum, to help keep the hatch from leaking through its rubber seals. The CFD was performed at the heat pump side of the system. Results from this was useful in identifying wake regions near the inlet and outlet, but also in quantifying potential in future aero dynamical improvements. The geometry improvement consisted of moving the compressor component in the hope to reduce pressure losses close to the inlet of the heat pump, and also to achieve a more even distribution of flow for the condenser but the results that showed the compressor placement had no relevance to either conditions.