The invention discloses a vertical humidifier with a variable-
diameter evaporator, and belongs to an evaporative humidifier. The humidifier comprises a housing, wherein an evaporating water tank is arranged in the housing, an
evaporator is arranged in the evaporating water tank, a fan is installed below the
evaporator, and the air inlet end of the fan communicates with an air inlet of the housing;a
water storage tank is further installed on the upper part of the evaporating water tank, the evaporator surrounds the lower part of the
water storage tank, and the
water storage tank further communicates with the evaporating water tank through a water inlet; and an air outlet is formed in the upper part of the housing, the air outlet communicates with the air outlet end of the fan, and the evaporator is arranged in an
airflow channel between the air outlet and the air outlet end of the fan. The fan is installed on the lower part of the evaporator, so that operating
noise waves pass throughthe evaporator and are reduced, and
silence is realized; the turbulence and
mass transfer effects of
airflow can be increased by the variable-
diameter evaporator with a tight lower end and a loose upper end, so that the humidification amount is effectively increased; and additionally, a vertical compact product structure surrounded by the variable-
diameter evaporator is adopted, so that the size of the evaporator is smaller.