A method for transferring fluid within a processing device, the method comprising: providing a processing device comprising at least one process array that comprises a first chamber and thermal transfer structure containing resident fluid, wherein the thermal transfer structure comprises a transfer conduit connected to the first chamber at a first port, wherein the first chamber includes an upstream end and a downstream end, and wherein the first port is located at an intermediate location between the upstream end and the downstream end; providing analyte in the first chamber; passing a first portion of the resident fluid through the transfer conduit into the analyte in the first chamber by heating at least a portion of the resident fluid in the thermal transfer structure such that the volume of the resident fluid within the thermal transfer structure increases to force the first portion of the resident fluid into the first chamber; cooling the heated resident fluid in the thermal transfer structure after passing the first portion of the resident fluid into the first chamber, wherein the volume of the resident fluid within the thermal transfer structure decreases such that at least a portion of the analyte in the first chamber is drawn into the thermal transfer structure through the transfer conduit; and wherein the process array comprises a second chamber and a second conduit extending between the second chamber and the first chamber, wherein the method comprises delivering fluid from the second chamber to the first chamber through the second conduit by rotating the processing device about an axis of rotation which coincides with the center of the processing device. providing a processing device comprising at least one process array that comprises a first chamber and thermal transfer structure containing resident fluid, wherein the thermal transfer structure comprises a transfer conduit connected to the first chamber at a first port, wherein the first chamber includes an upstream end and a downstream end, and wherein the first port is located at an intermediate location between the upstream end and the downstream end; providing analyte in the first chamber; passing a first portion of the resident fluid through the transfer conduit into the analyte in the first chamber by heating at least a portion of the resident fluid in the thermal transfer structure such that the volume of the resident fluid within the thermal transfer structure increases to force the first portion of the resident fluid into the first chamber; cooling the heated resident fluid in the thermal transfer structure after passing the first portion of the resident fluid into the first chamber, wherein the volume of the resident fluid within the thermal transfer structure decreases such that at least a portion of the analyte in the first chamber is drawn into the thermal transfer structure through the transfer conduit; and wherein the process array comprises a second chamber and a second conduit extending between the second chamber and the first chamber, wherein the method comprises delivering fluid from the second chamber to the first chamber through the second conduit by rotating the processing device about an axis of rotation which coincides with the center of the processing device.