Interaction mechanism of water movement and gas desorption during spontaneous imbibition in gas-bearing coal

•The greater the gas pressure around the capillary with one end opening, the more obvious the plugging effect.•A multi-branched capillary bundle model is established.•The lower the gas pressure, the better the wetting effect on the micropores and some mesopores.•Spontaneous imbibition can be used as a supplementary measure to promote gas drainage.