A wall assembly for use within a gas turbine engine, comprising: a multiple of liner panels ; and a support shell with a contoured region that forms a cavity between the support shell and at least one of the multiple of liner panels ; wherein: the contoured region extends toward a forward circumferential rail and an aft circumferential rail that extend from at least one of the multiple of liner panels ; and an intermediate circumferential rail of the at least one of the multiple of liner panels is between the forward circumferential rail and the aft circumferential rail ; wherein the cavity is subdivided by the intermediate circumferential rail into a forward cavity that converges towards the forward circumferential rail and an aft cavity that converges towards the aft circumferential rail ; wherein a multiple of cooling impingement passages penetrate through the support shell on each respective side of the intermediate circumferential rail ; wherein a multiple of effusion passages penetrate through each of the liner panels and include a forward effusion passage and an aft effusion passage ; wherein the forward cavity and the aft cavity accelerate and direct impingement airflow from the impingement passages towards the forward and aft effusion passages . a multiple of liner panels ; and a support shell with a contoured region that forms a cavity between the support shell and at least one of the multiple of liner panels ; wherein: the contoured region extends toward a forward circumferential rail and an aft circumferential rail that extend from at least one of the multiple of liner panels ; and an intermediate circumferential rail of the at least one of the multiple of liner panels is between the forward circumferential rail and the aft circumferential rail ; wherein the cavity is subdivided by the intermediate circumferential rail into a forward cavity that converges towards the forward circumferential rail and an aft cavity that converges towards the aft circumferential rail ; wherein a multiple of cooling impingement passages penetrate through the support shell on each respective side of the intermediate circumferential rail ; wherein a multiple of effusion passages penetrate through each of the liner panels and include a forward effusion passage and an aft effusion passage ; wherein the forward cavity and the aft cavity accelerate and direct impingement airflow from the impingement passages towards the forward and aft effusion passages . the contoured region extends toward a forward circumferential rail and an aft circumferential rail that extend from at least one of the multiple of liner panels ; and an intermediate circumferential rail of the at least one of the multiple of liner panels is between the forward circumferential rail and the aft circumferential rail ; wherein the cavity is subdivided by the intermediate circumferential rail into a forward cavity that converges towards the forward circumferential rail and an aft cavity that converges towards the aft circumferential rail ; wherein a multiple of cooling impingement passages penetrate through the support shell on each respective side of the intermediate circumferential rail ; wherein a multiple of effusion passages penetrate through each of the liner panels and include a forward effusion passage and an aft effusion passage ; wherein the forward cavity and the aft cavity accelerate and direct impingement airflow from the impingement passages towards the forward and aft effusion passages . <EOS>