Natural convection in a non-rectangular cavity, with the thermally-insulated non-vertical sidewalls or isothermal non-horizontal endwalls, is examined. The top horizontal endwall is at higher temperature than the bottom horizontal endwall. Emphasis is placed on ascertaining the initiation of flow by the local baroclincity in the immediate vicinity of the non-vertical or horizontal section of the wall. Comprehensive numerical solutions are obtained to the governing Navier-Stokes equations with Boussinesq-fluid approximation. For an exemplary a cavity with slanted sidewalls or endwalls, details of the flow and temperature fields are portrayed. The global heat transport through the cavity, expressed by the total heat transport ratio compared with rectangular cavity, is shown to be augmented as the system Rayleigh number and the incline angle increase. For the case of an oscillating sidewall form, numerical results demonstrate the presence of a series of mini-cavities. The global heat transport compared with rectangular case decrease as insulated sidewall is more oscillatory.
