Acoustical burner control system and method

An acoustically operated burner control system for optimally controlling a flow of air and fuel into a flame-producing combustion burner throughout a range of firing rates, comprising:

• first and second valve assemblies for modulating the flow of air and fuel into the burner;
• a microphone means for generating an electrical signal indicative of the aggregate intensity of all sounds generated by said combustion flame that are above 1 Khz in frequency,
• an acoustical waveguide for acoustically coupling said microphone means to said flame and isolating the microphone means from the heat generated by the flame, and
• a controller operatively connected to the first and second valve assemblies and electrically connected to said microphone means for maintaining the aggregate sound intensity of all sounds generated by said combustion flame that are above 1 Khz in frequency at a pre-selected level associated with optimality at each point within said range of burner firing rates.

An acoustically operated burner control system for optimally controlling a flow of air and fuel into a flame-producing combustion burner throughout a range of firing rates, comprising:

• first and second valve assemblies for modulating the flow of air and fuel into the burner;
• a microphone means for generating an electrical signal indicative of the aggregate intensity of all sounds generated by said combustion flame that are above 1 Khz in frequency;
• an acoustical waveguide having a distal end disposed within the envelope of said combustion flame for acoustically coupling said microphone means to said flame and isolating the microphone means from the heat generated by the flame, and
• a controller operatively connected to the first and second valve assemblies and electrically connected to said microphone means for maintaining the aggregate sound intensity of all sounds generated by said combustion flame that are above 1 Khz in frequency at a pre-selected level associated with optimality at each point within said range of burner firing rates.

An acoustically operated burner control system for optimally controlling a flow of air and fuel into a flame producing combustion burner throughout a range of firing rates, comprising:

• first and second electrically operated valve assemblies for modulating the flow of air and fuel into the burner;
• a microphone means of generating an electrical signal indicative of the aggregate intensity of all sounds generated by said combustion flame having a frequency above 10 Khz;
• a solid acoustical waveguide having a distal end disposed within the envelope of said combustion flame for acoustically coupling said microphone means directly to the envelope of said flame and isolating the microphone means from the heat generated by the flame;
• a probe means for establishing the aggregate sound intensity associated with an optimal flow of air and fuel into the burner for each point throughout the firing range of the burner, and
• a controller including a microprocessor having a memory for storing each of said sound levels associated with optimality, an output electrically connected to said first and second valve assemblies;
• and an input electrically connected to said microphone means, wherein said controller maintains the aggregate sound intensity of all sounds having a frequency above 10 Khz that are associated with optimality at each point along said firing range of said burner by modulating said valve assemblies to equate the sound intensity sensed by said microphone means with the sound intensity entered into said microprocessor memory, and wherein each level of optimality is associated with an aggregate sound intensity which is less than the sound intensity associated with an excess air condition but greater than the sound intensity associated with an excess fuel condition.

A method for optimally controlling a burner control system that includes an air valve assembly and a fuel valve assembly for modulating air and fuel to a flame producing combustion burner over a range of firing rates, comprising the steps of:

• monitoring the level sound intensity of all sounds produced by the combustion flame of the burner by a microphone means acoustically coupled to the flame by a solid acoustical waveguide having a distal end disposed within the envelope of said combustion flame;
• obtaining, for a plurality of points long said range of firing rates, the sound intensity level associated with stoichiometric optimality by measuring the level of intensity of all sounds having frequencies of over 10 Khz generated by said combustion flame when said burner is burning air and fuel at a stoichiometric ratio at said points along said firing rate;
• interpolating and recording a sound level for each point along the firing range of said burner that is associated with optimality;
• operating said burner at a selected point along said firing range, and
• maintaining the sound intensity level of all sounds generated by the combustion flame having acoustical frequencies of over 10 Khz at the optimal sound level associated with said selected point along said firing range by adjusting said valve assemblies.