摘要:
A method of absorption spectroscopy to determine a rapidly variable gas parameter. The method includes transmitting light from a synchronization light source to a synchronization detector. The transmitted light is periodically interrupted by a moving mechanical part between the synchronization light source and synchronization detector. The output from the synchronization detector is used to generate a repeating time signal having variable phase delay. This signal is used to control the timing of laser spectroscopy wavelength scans. Multiple spectroscopic scans may be repeated at multiple selected time signal phase delay and the results averaged for each phase. Apparatus for implementing the above methods are also disclosed.
摘要:
A method of monitoring combustion properties in an interior of a boiler of the type having walls comprising a plurality of parallel steam tubes separated by a metal membrane. First and second penetrations are provided in the metal membrane between adjacent tubes on opposite sides of the boiler. A beam of light is projected through a pitch optic comprising a pitch collimating lens and a pitch relay lens, both residing outside the boiler interior. The pitch relay lens projects the beam through a penetration into the boiler interior. The beam of light is received with a catch optic substantially identical to the pitch optic residing outside the boiler interior. The strength of the collimated received beam of light is determined. At least one of the pitch collimating lens and the catch collimating lens may then be aligned to maximize the strength of the collimated received beam.
摘要:
A method of monitoring combustion properties in an interior of a boiler of the type having walls comprising a plurality of parallel steam tubes separated by a metal membrane. First and second penetrations are provided in the metal membrane between adjacent tubes on opposite sides of the boiler. A beam of light is projected through a pitch optic comprising a pitch collimating lens and a pitch relay lens, both residing outside the boiler interior. The pitch relay lens projects the beam through a penetration into the boiler interior. The beam of light is received with a catch optic substantially identical to the pitch optic residing outside the boiler interior. The strength of the collimated received beam of light is determined. At least one of the pitch collimating lens and the catch collimating lens may then be aligned to maximize the strength of the collimated received beam.
摘要:
A method for measuring combustion parameters within a combustion zone of a gas turbine engine, the combustion zone being defined between an inner and outer casing. The method includes transmitting a beam from a transmit optic optically coupled to a bore in the outer casing off a portion of the inner casing and receiving a portion of the beam reflected off the inner casing with a receiving optic optically coupled to a bore in the outer casing. An apparatus for practicing the method includes a laser generating a beam and a transmitting/receiving optics pair, the transmitting/receiving optics pair being configured for operative association with a port in an outer casing of a gas turbine engine, whereby the transmitting/receiving optics are in optical communication by reflecting the beam off a portion of an inner casing.
摘要:
A method of measuring the combustion property in a measurement volume within a casing defined in part by a casing wall. The method includes providing a port in the chamber wall. Also provided is a fiber assembly comprising a single mode transmit core surrounded by a multimode receive core means. The fiber assembly is operatively coupled to the port to provide optical communication between the fiber assembly and measurement volume. A detection beam capable of detecting a select combustion property is transmitted from the single mode fiber and reflected off a reflection surface within the chamber, the reflection surface being configured to reflect and optically couple at least a portion of the detection beam to the multimode receive core means. The detection beam optically coupled to the multimode receive core means is then measured.
摘要:
A method for measuring combustion parameters within a combustion zone of a gas turbine engine, the combustion zone being defined between an inner and outer casing. The method comprises transmitting a beam from a transmit optic optically coupled to a bore in the outer casing off a portion of the inner casing and receiving a portion of the beam reflected off the inner casing with a receiving optic optically coupled to a bore in the outer casing. An apparatus for practicing the method comprises a laser generating a beam and a transmitting/receiving optics pair, the transmitting/receiving optics pair being configured for operative association with a port in an outer casing of a gas turbine engine, whereby the transmitting/receiving optics are in optical communication by reflecting the beam off a portion of an inner casing.
摘要:
An apparatus and methods for measuring combustion parameters in the measurement zone of a gas turbine engine. The measurement zone is defined as being between an outer casing and an engine component having a reflecting surface inside the outer casing. The apparatus comprises a laser generating a transmitting beam of light of a select wavelength and a multimode transmitting fiber optically coupled to the laser. A transmitting optic is optically coupled to the multimode optical fiber for transmitting the beam into the measurement zone. The reflecting surface is configured to provide a Lambertian reflection. A receiving optic is positioned to receive the Lambertian reflection. Means are provided in operative association with the multimode transmitting fiber for averaging modal noise induced signal level variation of light propagating within the multimode transmitting fiber.
摘要:
A method of absorption spectroscopy including obtaining absorption data at multiple wavelengths along more than one line-of-sight path through a quantity of gas of interest. The method further includes identifying more than one temperature and gas species concentration bin along the multiple line-of-sight paths and creating a map of temperature and gas species concentration. The map thus created will have at least two-dimensional information derived from select temperature and gas species concentration bins identified along more than one line-of-sight path. Apparatus for implementing the above method is also disclosed.
摘要:
A pitch side optical system for use in diode laser spectroscopy consisting of more than one diode laser having select lasing frequencies with each diode laser being coupled to an end of a distinct input optical fiber. The pitch side optical system further consists of a multiplexer optically coupled to the other end of less than all of the input optical fibers with the multiplexer outputting multiplexed laser light to a pitch side optical fiber. The pitch side optical system further consists of a coupler optically coupled to the far end of the pitch side optical fiber and the far end of an unmultiplexed input optical fiber with the coupler combining the multiplexed laser light and the unmultiplexed laser light and outputting the combined light to a transmission optical fiber. Typically, the coupler is located near the combustion process. The pitch side optical system further consists of a pitch optic coupled to the transmission optical fiber. Typically, all optical fibers used in the pitch side optical system are single mode optical fibers.
摘要:
A method of sensing a process utilizing a sensing apparatus consisting of more than one diode laser having select lasing frequencies, a multiplexer optically coupled to the outputs of the diode lasers with the multiplexer being further optically coupled to a pitch side optical fiber. Multiplexed laser light is transmitted through the pitch side optical fiber to a pitch optic operatively associated with a process chamber which may be a combustion chamber or the boiler of a coal or gas fired power plant. The pitch optic is oriented to project multiplexed laser output through the process chamber. Also operatively oriented with the process chamber is a catch optic in optical communication with the pitch optic to receive the multiplexed laser output projected through the process chamber. The catch optic is optically coupled to an optical fiber which transmits the multiplexed laser output to a demultiplexer. The demultiplexer demultiplexes the laser light and optically couples the select lasing frequencies of light to a detector with the detector being sensitive to one of the select lasing frequencies.