Tumble dryer works on principle of drawing in air through vents which is then heated and distributed throughout the drum to draw moisture from clothing. The air is blown and recirculated throughout the system by a forward curved radial fan which has a flat characteristic curve with distinct volatile area which has a negative impact on drying process. Measurements of aerodynamic properties defined the operation characteristic of the named fan and the operation characteristics in the volatile area. With intentions of running the equipment at the stable part of the curve we mathematically analyzed the effect of spinning frequency, diameter and fan height on operating characteristics. The most suitable combination from the previously listed parameters was chosen, which was based on geometrical adjustment of the fan. After that followed the manufacturing and installation of the adjusted fan on which we made aerodynamic characteristics measurement. Results of the mathematical analysis confirmed successful calculation of the adjusted fan. With the adjusted fan and the chosen mass of laundry we executed functionality tests of which the results showed 8 percent shorter drying cycles, power consumption dropped by 2 percent and lower values of pressure fluctuation were noticed.
|