Partially transitioned flame start-up of a perforated flame holder

Abstract

A combustion system includes a perforated flame holder configured to hold a main combustion reaction substantially between input and output faces thereof. A main fuel nozzle is positioned to emit a main fuel stream toward the input face. An igniter assembly is configured to ignite a preheat flame supported by the main fuel stream between the main fuel nozzle and the perforated flame holder, and to selectably control a degree of ignition of the fuel stream by the preheat flame. During a start-up of the combustion system, the perforated flame holder is preheated by the preheat flame. When the perforated flame holder reaches a start-up temperature, the preheat flame is shifted from fully igniting to partially igniting the fuel stream, allowing fuel and oxidant to reach the perforated flame holder. A flame is ignited in the perforated flame holder while the preheat flame burns. The preheat flame is then released.

Dependencies are inferred from the claim text.