The present disclosure is directed to a combustor including an annularly shaped liner that at least partially defines a hot gas path of the combustor and a flow sleeve that circumferentially surrounds at least a portion of the liner. The flow sleeve is radially spaced from the liner to form a cooling flow annulus therebetween. A plurality of fuel injector assemblies circumferentially spaced about the flow sleeve and each fuel injector assembly extends radially through the flow sleeve, the cooling flow annulus and the liner. A first portion of the flow sleeve defined between a first pair of circumferentially adjacent fuel injector assemblies of the plurality of fuel injector assemblies bulges radially outwardly with respect to an outer surface of the liner so as to enlarge a flow volume of the cooling flow annulus.