溶液在单管程列管换热器的管内流动,其对流传热系数为500W/(m.℃),若吧单程管改为双管程,其他条件不变,
此时对流传热系数是?
A770500W/(m.℃)B870W/(m.℃)
C970W/(m.℃)D1000W/(m.℃),