Method of producing melt, method of producing glass article, melting apparatus, and equipment for producing glass article

A method of producing a melt, comprising:

• directly contacting a first heating element with an inside of a solid-liquid mixture layer including a batch raw material of glass and a mixture of solid and liquid phases denatured from the batch raw material to apply thermal energy to the solid-liquid mixture layer by heat transfer from the first heating element;
• supplying the batch raw material from above the solid-liquid mixture layer;
• and
• continuously producing a liquid phase melt without using electrodes to Joule heat the solid-liquid mixture layer, the liquid phase melt having a bulk density greater than that of the solid-liquid mixture layer in a lower layer in contact with the solid-liquid mixture layer,
• wherein a thermal diffusivity of the solid-liquid mixture layer is 3 mm2/second or less, the first heating element includes an electric resistance heating element or a heat exchanger tube, and the first heating element does not include electrodes for Joule heating the melt.