关键词: 射频, 液体加热, 阳栅比, 升温速率

Abstract:

Radio frequency (RF) electromagnetic wave has the advantages of high penetration depth and fast heating speed, which could save time in food sterilization process and preserve the nutrient contents and high quality of food to the largest extent. Taking tap water and sodium chloride solution as material, this paper studied the affecting regulation of factors on electric fluid ratio of anode to grid and the liquid heating rate by RF heating. Those factors included liquids height-diameter ratio, liquid air ratio and electrical conductivity. The results showed that when the liquid air ration was changing, the electric fluid ratio of anode to grid of RF heating machine first went up, then reduced and reached the maximum value. The lager was the electric fluid ratio of anode to grid, the faster was the RF heating speed. The larger the height-diameter ration was, the quicker of RF heating was. When the electrical conductivity of liquid was around 900~1 000 μs/cm, the electric fluid ratio of anode to grid was relatively larger and the RF heating of liquid was also relatively faster.

Key words: radio frequency, liquid , heating, electric fluid ratio of anode to grid, temperature increasing speed rate