A premixed partial oxidation (POx) syngas generator is provided. The syngas generator includes a premixing device configured to mix a fuel stream and oxygen in a premixing region to form a gaseous pre-mix. The premixing device includes a fuel inlet configured to introduce the fuel stream within the premixing device and a flow conditioning device configured to pre-condition the fuel stream. The premixing device also includes an oxygen inlet configured to introduce oxygen into the fuel stream to facilitate premixing of the fuel stream and oxygen in the premixing region located downstream of the flow conditioning device. The syngas generator also includes a combustion chamber configured to combust the gaseous pre-mix from the premixing device to produce a synthesis gas enriched with carbon monoxide and hydrogen gas.