Determination of ion wind velocity using the method of characteristics (MOC) and its application for drying of black turmeric (Curcuma aeruginosa Roxb) slices

Abstract

Ion wind drying also called corona wind drying in this study using a pin-multi ring concentric electrode. The purpose of the research is to determine the velocity of the ion wind by the characteristic of the method (MOC) and to apply it for drying the black turmeric (Curcuma aeruginosa Roxb). In theory, the ion wind velocity is equal to the ion mobility multiplied by the electric field. In MOC, the ion mobility is obtained from the graph of the relationship between the electric corona discharge current and the applied high voltage. The ion wind produced by corona discharge has been drying of the black turmeric slices with an applied high voltage 4 kV, the gap electrode 6 mm and drying time 0-30 minutes with a 5 minute time interval. Sliced black turmeric was circle formed with a radius of 15 mm and a thickness of 2-8 mm with an interval of 2 mm thickness. According to the results obtained, a constant of comparing the ion wind velocity with the MOC.. Its value is around 102 which is hypotheses of the value of the relative permittivity the ion wind. The drying rate maximum of the black turmeric (Curcuma aeruginosa Roxb) slices occurs at the beginning of drying is after a 5 minute drying time. This characteristic for all the variations of the samples radius. This causes the moisture content of the black turmeric slices to drop drastically.