System and method for a high spatial resolution multipoint sensing of process parameters

Abstract

A high spatial resolution multipoint sensor having a plurality of sensor elements, each arranged at a respective plurality of discrete locations for sensing process parameters at the respective discrete locations, and a carrier having the plurality of sensor elements are arranged thereon, the carrier including a first material for maximizing sensitivity of the sensor elements to the sensed process parameter, and a second material for minimizing coupling of the sensed parameter between the sensors wherein the first material is arranged on the carrier at each discrete location and the second material is arranged on the carrier between the discrete locations to thereby minimize coupling of the sensed process parameters between adjacent sensor elements and allow closer spacing of sensor elements. The sensor can measure multiple closely spaced parameters simultaneously with minimal interference from neighboring sensors.

Description

System And Method for a High Spatial Resolution Multipoint Sensing of Process ParametersCross Reference to Related Applications

[0001] This application claims priority to US provisional patent application No. 63472382, filed June 12, 2023, the entirety of which is incorporated herein by reference.Field

[0002] The present matter relates to the field of multipoint sensing, and more particularly to methods and systems for high spatial resolution multipoint sensors such as optical fiber cables.Background

[0003] Intelligent sensing techniques are important in monitoring critical parameters in industries, such as steel industries, civil engineering, and power industries provide remote and continuous monitoring of process parameters for condition-based maintenance, reduced use of human involvement, remote monitoring of key components, and autonomous operation. Intelligent sensing techniques are particularly important during severe industrial accidents and post-accident recovery such as those at nuclear power plants. Of the various parameters monitored, temperature is one of the more important measured parameters in practice. For example, accurate temperature monitoring is important for ensuring, amongst others, product quality and process safety, and detecting equipment malfunctions. Monitoring and controlling battery pack temperature dynamics is critically important. Large-scale devices, such as electric vehicles and grid-scale energy storage require battery packs to be constructed with thousands of cells. There is a need for temperature monitoring of these battery packs which may develop so called localized hot spots. Temperature sensors are utilized to provide cartographies of temperature of shields for spacecraft or aircraft wings.

[0004] In industrial applications, multipoint temperature detecting techniques have been used for their ability to measure temperature with high spatial resolution. Contact-free techniques, such asinfrared imaging, can detect temperature variations over a large area and from a distance with high spatial resolution, but require a clear path to the sensing area without obscuring objects in the field of view between the detector and the objects or sensed area. Another technique uses microelectromechanical systems (MEMS) sensors which are small, highly sensitive sensors that can detect temperature variations with high degree of spatial resolution. MEMS sensors can be integrated into other devices, such as smartphones or wearables, allowing for temperature monitoring in real-time, but they typically operate in a temperature range between -40°C and 125°C, which may not be wide enough for some applications. Contact techniques, such as, thermocouples (TC), resistance temperature detectors (RTD), and thermistors can be arranged in an array to achieve a high spatial resolution. However, these arrays are typically used in applications where temperature variations occur over a small area. On the other hand, the thermistor array may be encapsulated in protective probes, and non-conductive material to isolate power supply wires and signal wires for their protection and minimize their impacts on temperature profile. For applications require acquiring data from multiple locations, sensor output wiring can be problematic, if applications have limited deployable space, then cabling may pose even more challenging.

[0005] Another promising solution is based on optical fiber sensors (OFSs) or fiber optic sensors (FOSs), which use optical fiber as the sensing element and the signal channel. OFSs may be used to detect temperature variations with high degree of spatial resolution. The fiber optic sensors consist of a temperature-sensitive elements that change the optical properties in response to variations in temperatures in localized areas. The OFSs can be embedded in the object or placed on the surface of the object to measure the variations of temperature, strain, and vibrations. They are compact in size and are capable of surviving in harsh environments. Other features, such as low attenuation loss, broad bandwidth, and multiplexing sensing ability, make OFS a competitive candidate that can acquire temperatures at multiple measurement points by using a single optical fiber. Its passive sensing capability does not require on-site power at the sensing points. The compact OFSs can be integrated into key components, which lead them to be intelligent embedded components and structures. A spatially distributed optical fiber temperature sensor has been used in a steel industry, where the sensor has survived both mechanically and optically at a temperature exceeding 700 °C. If special materials, such as Sapphire, are used, it can survive at 1800 °C. In the nuclear industry, OFSs are used in normal operations and during an accident to enhance the safetyof nuclear power plants (NPPs). They are used to monitor temperatures of a reactor, steam pipes, and spent fuel pools. They have also been used to detect fire within the reactor and auxiliary buildings. Rayleigh-backscatter-based distributed OFSs have been deployed to obtain high- resolution liquid-sodium temperature measurements. Two fiber-optic distributed temperature sensors (DTS) have been used to map the temperature distribution inside a 19-rod bundle. A fiber Bragg grating (FBG) based OFS is not only used in a lab-scale test rig but also deployed in a commercial facility. For example, a sapphire FBG based multipoint temperature sensor was installed in boilers at a commercial power plant. The OFSs were probed into a coal-fired boiler and a gas-fired boiler. Although FBGs may be engraved in a series to detect temperatures at multilocations, these probes may lack spatial resolution due to ‘thermo-smear’ induced by the OFS protective cladding / sheath. For example, it has been shown that a high thermal conductivity copper tube may eradicate temperature gradients, making it difficult for the optical fiber to distinguish closely spaced temperature features from neighboring measurement points.

[0006] A capillary or protective sheath is needed to protect the OFSs since they are sensitive to strain. The capillary is typically made of high thermal conductivity material such as, stainless steel, which is also rigid and resistant to environmental degradation, And resistant to vibration, mechanical stresses, and aggressive / corrosive media. In addition, thermal lag between the sensing element and the medium being measured may cause changes to the thermal profile at the point of measurement. These effects can cause measurement errors, particularly in applications where rapid temperature changes occur.

[0007] It is recognized that the outputs of a multipoint temperature sensor represent approximations of the temperatures at locations when a conventional OFSs probe is immersed in a fluid or a solid. A variety of factors may cause deviations between the probe output and the actual temperature at points of interest. First, the presence of the probe itself may affect the thermal profile at the point and in its surroundings, thereby altering the temperature distribution. A second factor is that the sensor may affect the neighboring locations at which temperatures are being measured. For example, deviation between fluid and probe temperatures results from thermal leakage (or stem conduction), where the heat is conducted along the probe and out to the environment or the isothermal zone, thus causing the probe temperature to deviate from the actual temperature. The third factor is that the protective sheath can also act as a heat conduction pathbetween the sensing elements. This is referred to as thermal smearing. In addition, in transient processes, the heat capacity of the sensor introduces temperature lag behind any change of the interested environment, resulting in a response-rate “error”.Summary

[0008] In accordance with a general aspect there is provided monitoring methods and techniques for high resolution multipoint indirect or direct measurement of process parameters in challenging environments wherein measurements are made at multiple spatially separate points. And further wherein for example the process parameters include but are not limited to temperature, pressure, or strain.

[0009] In accordance with one aspect of the present matter there is provided a high spatial resolution sensor for sensing process parameters in an environment, the sensor having a plurality of sensor elements, each arranged at a respective plurality of discrete locations for sensing process parameters at the respective discrete locations, and a carrier having the plurality of sensor elements are arranged and supported thereon, the carrier including a first material for maximizing sensitivity of the sensor elements to the sensed process parameter, and a second material for minimizing coupling of the sensed parameter between the sensors wherein the first material is arranged on the carrier at each discrete location and the second material is arranged on the carrier between the discrete locations to thereby minimize coupling of the sensed process parameters between adjacent sensor elements and allow closer spacing of sensor elements.

[0010] In accordance with an embodiment of the first aspect the first material is a conductor, and the second material is an insulator.[OH] In accordance with an embodiment of the first aspect the carrier is an optical fiber, and the sensor elements are optical fiber sensors.

[0012] In accordance with a further aspect of the present matter there is provided a high spatial resolution temperature sensor having a sensor carrier and temperature sensor elements arranged at distinct locations along the carrier for sensing temperature at the distinct locations on the sensor carrier, a first material arranged at the discrete locations, and a second material different to the firstmaterial configured and arranged on the carrier to minimize thermal shunting effects between the temperature sensor elements.

[0013] In accordance with another aspect of the present matter there is provided a high spatial resolution temperature sensing cable having a protective sheath, and temperature sensors arranged along the cable for measuring temperatures along an entire length of the sensor cable and wherein the sheath is configured to minimize thermal shunting effects between distinct temperature sensors.

[0014] In accordance with a further aspect of the present matter, the sheath at the sensing point is configured to minimize thermal lag and thereby minimize temperature errors.

[0015] In accordance with a further aspect of the present matter spatial resolution of the sensing elements are in a range of less than a millimeter to meters.

[0016] In accordance with another aspect of the present matter the sensing cable is an optical fiber cable.

[0017] In accordance with another aspect of the present matter the sheath provides mechanical support and protection for the sensing cable.

[0018] In accordance with an embodiment of the present matter, the spacing of the temperature sensors determines the spatial resolution. In an embodiment the spacing is in a range of less than a millimeter to a few millimeters.

[0019] In another aspect there is provided an optical fiber temperature sensing element comprising a probe having a segmented structure configured to form a conductor-insulator-conductor structure for minimizing thermal shunting effects to provide high spatial resolution temperature measurement while providing a mechanically protective sheath around the optical fiber.

[0020] In another aspect the optical fiber temperature sensing element includes adjacent OFSs to detect temperatures independently having reduced thermal smearing between adjacent OFSs.

[0021] In another aspect the optical fiber temperature sensing element has improved resolution by staggering an arrangement of the sensor cables.

[0022] In accordance with a still further aspect of the present matter there is provided a sensor system for measuring a physical property of an environment including a high spatial resolution sensor according to embodiments of the present matter, a light source, a light detection module, and a signal processing module, wherein the high spatial resolution sensor is coupled to the light source and wherein the light detection module detects light properties resulting from interaction of sensor elements with environment parameters being measured, the detected light properties being processed by the signal processing module to produce a signal indicative of the physical property being measured.

[0023] In accordance with another aspect of the present matter the cable is a multicore cable.

[0024] In accordance with another embodiment of the first aspect of the present matter the sensor is configured for the sensing of process parameters simultaneously in one of a linear arrangement, in a planar arrangement or in three-dimensional arrangement.

[0025] Many further features and combinations thereof concerning embodiments described herein will appear to those skilled in the art following a reading of the instant disclosure.Brief Description of the Drawings

[0026] Embodiments of the present matter will now be described by way of example with reference to the accompanying drawings in which like references denote similar elements, and in which:FIG. 1A and FIG. IB show, respectively, a schematic diagram of an optical fiber sensor (OFS) probe with five sensing points and a partial cross-sectional view of the probe along a section line a-a;FIG. 2A and 2B show a simplified model of an equivalent thermal circuit for the probe;FIG. 3A shows a single segment cladding structure according to an embodiment of the present matter;FIG. 3B shows a multi-segment cladding structure according to an embodiment of the present matter;FIG. 4A-4C show a model and different cladding of the sensor for evaluating smear effect caused by thermal shunting according to an embodiment of the present matter;FIG. 5 shows a plot of temperature versus distance along a sensor according to an embodiment of the present matter; andFIG. 6 shows an illustration of a staggered arrangement of two sensors in accordance with an embodiment of the present matter.Detailed Description

[0027] The detailed description set forth below is intended as a description of exemplary designs of the present disclosure and is not intended to represent the only designs in which the present disclosure can be practiced. The term “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other designs. The detailed description includes specific details for purposes of providing a thorough understanding of the exemplary designs of the present disclosure. It will be apparent to those skilled in the art that the exemplary designs described herein may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the novelty of the exemplary designs presented herein. In the description and drawings numerals are used to indicate similar structures and features. In the present description spatial resolution refers to distance between independent measurement locations, or a physical dimension. High spatial resolution refers to a reduced distance between independent measurement locations. In other words, sensor or measurement locations may be placed closer together and still differentiate between these measurements.

[0028] The present matter provides a high spatial resolution sensor having a plurality of sensor elements, each arranged at a respective plurality of discrete locations for sensing process parameters at the respective discrete locations, and a carrier having the plurality of sensor elements are arranged thereon, the carrier including a first material for maximizing sensitivity of the sensor elements to the sensed process parameter, and a second material for minimizing coupling of thesensed parameter between the sensors wherein the first material is arranged on the carrier at each discrete location and the second material is arranged on the carrier between the discrete locations to thereby minimize coupling of the sensed process parameters between adjacent sensor elements and allow closer spacing of sensor elements.

[0029] In the following description an exemplary temperature measurement sensor is described in accordance with an embodiment of the present matter.

[0030] Referring to FIG. 1A and FIG. IB there is shown, a schematic diagram of a sheathed multipoint temperature probe 100 and a partial cross-section 120, respectively. A sheathed multipoint temperature probe comprises a high-density ceramic insulation, typically magnesium oxide, and then encased within a metal sheath. Common sheath materials are copper, stainless steel or Alloy 600, but any suitable metal could be used. As mentioned earlier, OFSs are sensitive to strain, a capillary or protective sheath is required to protect the OFSs. The probe 100 further includes wires 101 connecting to a processing block (not shown) for coupling signals to and from the multipoint sensors. Generally, this processing block may be located away from the sensor (depending on the environment) or at one end of the probe.

[0031] Referring back to FIG.’s 1A and IB, the temperature probe 100 includes a cylindrical multipoint sensing probe 112 having an optical fiber core 113 incorporating spaced sensing locations 102, 104, 106, 108 and 110 with correspondingly located sensor elements, an outer sheath 114, and an inner concentric ceramic type of material 116, surrounding the optical fiber 113. The ceramic material 116 is preferably a high thermal conductive material to reduce thermal lag in a radial direction of the cylindrical probe 112, while providing a thermal path along an axial direction.

[0032] In the probe 100, heat is transferred through different types of material, such as the sheath 114 and the ceramic insulation material 116, due to a temperature (T) gradient, which can be described by Fourier’s law stated as, dT pc— = V ■ kVT (1) where p is the density and c is the specific heat of the material, k is referred to the thermal conductivity of the material and has units of W / m ■ K, when a thermal perturbation is applied at some point in a medium.

[0033] Referring to FIG. 2A there is shown a schematic diagram of a portion 200 of the temperature probe 100 for a pair of spaced sensor elements Si and S2 and in FIG. 2B there is shown an equivalent thermal circuit model 220, according to an embodiment of the present matter. As illustrated the sensor elements Si and S2 are located at distinct locations along the probe, and spatially separated by a distance Li. In other words, the distance Li determines the special resolution of this portion of the probe. Let the environment temperature of a small area (201) of the probe be Ti. Note 201 is aligned to the location of Si and the effective convective thermal resistance is Ro. Taking the role of sheath into thermal resistance network analysis, heat is transferred to the location, 202, of sensor element S2through the sheath along a path Pxand also through the ceramic material along a path P2. Each of the materials have a respective thermal conductivity of kxand k2. Therefore, Rx= Lj / kjAj and R2= L2 / k2A2are the thermal resistances of Pxand P2. The overall thermal resistance between 201 and 202, R, (K / W), in the probe is given by:where L1?L2are the distances (m) between the measured point (201) and the sensor location (202) S2through the path Pxand P2. Axand A2are the cross-section area (m2) perpendicular to the path of heat flow. Form equation (2) it may be seen that the thermal resistance R decreases as kxincreases, it means when the sheath is applied, the overall resistance R decreases. As a result, the temperature detected at the location of sensor S2is higher than the temperature detected without the sheath. This phenomenon is similar to the short circuit that happened to the electrical circuit: a conductive wire / path averages the temperatures.

[0034] In the present illustrative embodiment, a high spatial resolution temperature sensor is described. The temperature sensor is implemented with multiple senor elements such as FBGs temperature sensor elements constructed in short segments along multiple distinct locations of the optical fiber. In order to achieve a high spatial resolution sensor each FBG in the plurality of FBGs should preferably distinctively acquire the temperature at its distinct location along the multipoint OFS with little or no interference from temperature at locations of adjacent or distant FBGs on the OFS.

[0035] The FBGs sensor elements are used as an illustrative embodiment of the general principles applicable to a sensor carrier according to the present matter. While operating principles of FBG-based OFSs are well known, they may be summarized as follows. The OFS uses the light propagating in the optical fiber to detect the measurement parameter. The principle of the sensor based on the Bragg grating is to detect the shift in wavelength of the reflected ‘Bragg’ light, which corresponds to the change of the environment (in this case temperature) of the sensing spot. To theoretically investigate the FBG, analyzing the light propagation in the optical fibers with a perturbation is to solve Maxwell’s equations with appropriate boundary conditions, the normally applied technique is based on the coupled-mode theory and the wavelength of reflected light is expressed as:where E is the applied strain, P; coefficients are the Pockel’s coefficients the stress-optic tensor, v is Poisson’s ratio, aA= stands for the coefficient of thermal expansion of the fiber material,an= - -s— presents the thermo-optic coefficient, while AT is the change in temperature. For a neff dT complex grating, the transfer matrix method is applied to analyze the behaviors of Bragg gratings. As Eq. (2) implies, to eliminate or decrease the thermal shunting effect introduced by the sheath while keeping a rapid response to the thermal perturbation, the sheath has to have a higher sensitivity to the perturbation at locations of sensing elements and a lower thermal conductivity elsewhere.

[0036] Referring to FIG. 3A there is shown a carrier structure 300 for a sensor according to another embodiment of the present matter. The sensor comprises FBGs based OFS 302 which includes a carrier 303 sheath comprised of a first material such as copper 304 and a second material such as polyetheretherketone (PEEK) 306 forming a cladding segment for the OFS. The cladding comprised of copper-PEEK (CP) segments may be repeated along the length of the OFS with the copper part of the segment located over the FBG and the PEEK part of the segment located in the spacing between adjacent FBGs as illustrated in the OFS 320 shown in FIG. 3B.

[0037] In other embodiments the structure is configured as Copper-PEEK, where multi-CP structures may be assembled as Copper-PEEK sections to protect the OFSs. Other types of OFSs not limited to FBGs may be used as sensing elements.

[0038] The structure for a sheath (cladding) or carrier according to the present matter comprises in one embodiment copper sections separated by a low conductivity section, which in oneembodiment may comprise a high-performance thermoplastic material having a low thermal conductivity, such as the PEEK. The thermal conductivity of copper and PEEK are 384.1 IV / m ■ K and 0.25 W / m • K, respectively.

[0039] In other embodiments low conductivity material, such as aerogel (0.013 W / m ■ K), which are extremely porous and very low in density materials, may be used to achieve improved performance.

[0040] In one embodiment, intervals between distinct locations of the FBGs sensor elements are 10 mm. In other embodiments, smaller or larger intervals may be used. Furthermore, a higher spatial resolution may be achieved by using distributed temperature sensing (DTS) sensors, which use the Raman effect to measure temperature, for example, the DTS sensor with a sensing element having a length of 1.04 mm and minimum sensor interval of 0.65 mm. In an embodiment the adjacent copper-PEEK segments are connected by being screwed together. In another embodiment the adjacent copper-PEEK segments are connected by snap connections. In a still further embodiment, the adjacent copper-PEEK segments are connected by glued connection.

[0041] Referring to FIG. 4A, there is shown 400 a schematic drawing of a modelled sensor 300 to illustrate a smear effect caused by thermal shunting as described earlier. A finite element method (FEM) model for numerical analysis of the thermal shunting effect is built in a general -purpose simulation software such as COMSOL Multiphysics®. Three heaters 402,404, 406 are arranged to introduce thermal perturbation. The heat sources are 100 W / m2. Five sensing elements are arranged linearly along the optical fiber 302 and spaced apart from the 0 mm to 110 mm. FIG. 4B shows a longitudinal cross-section of the sensor having a sandwich like sheath of Copper- PEEK-Copper and FIG. 4C shows a longitudinal cross-section of the probe with a copper sheath. In the illustrated embodiment the outer diameter of the tubular copper sheath is 0.8 mm and the inner diameter is 0.125 mm, which is same as the diameter of the bare optical fiber (SM25). The lengths of the copper and the PEEK are selected to be 10 mm.

[0042] Referring to FIG. 5 there is shown results of the numerical analysis, with temperature versus distance above the end of the probe. A line is plotted along an interface of the optical fiber and the inner wall of the copper. Four scenarios are investigated, namely bare OFS, sheathed with copper, without sensor (Air), and Copper-PEEK sheathed. In FIG. 5 a solid line with triangle represents the temperature detected by a bare OFS, which introduce the least disturbance to the exact temperature as shown by the dash-dot line. The dotted line is the temperature when a coppertube is employed to protect the OFS. The solid line is the temperature measurement when the OFS is protected by a Copper-PEEK sheath. From FIG. 5 it may be seen that a bare OFS performs better in detecting and tracking the temperature profile of the medium. However, it also exposes the fragile optical fiber to the environment. As a result, it is the least favourable design in a real- world application. As the dotted line indicates, when a copper is employed to protect the OFS, the thermal perturbation caused by three heaters can hardly be detected distinctly. The OFS protected by Copper-PEEK sheath has the capability of detecting the temperatures along the probe. However, for the copper sections, the thermal shunting effects may still be seen at both the ends of the probe. The results prove that the proposed Copper-PEEK protected OFSs is most effective in eliminating the thermal shunting caused by the metal sheath while achieving a high spatial resolution.

[0043] In summary, it may be concluded that a bare OFS is the most sensitive to monitor the nonisothermal layer, but it is also susceptible to strain disturbance caused by thermal fluids, especially during temperature transients.

[0044] Copper protected OFS is immune to strain disturbance, but it is less sensitive to capture the different non -isothermal layer, thus it is not suitable for applications requiring high spatial resolution.

[0045] The copper-PEEK protected OFS not only achieve a high spatial resolution, but also be able to detect the temperatures at different points, even the adjacent two isothermal layers can be detected distinctively.

[0046] The temperatures acquired from the copper protected are difficult to be decoupled because of the thermal shunting caused by the protective sheath while the bare OFS is susceptible to interference caused by strain. The proposed copper-PEEK protection achieves a high spatial resolution and is also able to detect the temperatures at different points, even the adjacent two isothermal layers can be detected. Furthermore, as OFSs are sensitive to strain, a protective structure according to the preset matter provides a suitably rigid sheath to protect the OFSs.

[0047] Referring to FIG. 6 there is shown an arrangement of the OFS to achieve a high spatial resolution in detecting non-isothermal layers in, for example, a process for melting and heating wax. In this arrangement spatial resolution is further improved by arranging two probes that are staggered and separated by a known distance Y (sensor elements in each probe being at a known distance in the X or axial direction) wherein the copper sections of the first sensor line up with the PEEK section of the second sensor. In a still further embodiment (not shown) multiple probes maybe arranged in this staggered arrangement. In a still further embodiment, the probes may be configured in a non staggered arrangement so that the PEEK-copper sections line up.

[0048] The temperature sensor structure according to embodiment of the present matter may be configured to operate in a temperature range exceeding that of typical MEMS which can only operate in a range between -40°C and 125°C. Furthermore, the protective carrier of the present matter reduces bulk and weight of the probes, which allows use in applications where space is limited or where the probe needs to be inserted into small or narrow spaces.

[0049] While the above embodiments have been described with respect to temperature sensors using OFS, other types of sensors may be implemented in accordance with embodiments of the present matter. For example, pressure and strain sensors based on OFS. In a strain sensor application, the second material may be chosen to allow an enhanced sensitivity of a sensor element to strain at distinct locations while the second material may minimize the pressure or strain effects on adjacent sensor element locations. Furthermore, while probes with a PEEK-Copper have been described in the above illustrative embodiments it is understood that any dissimilar materials may be configured in an arrangement according to the present matter to enhance the spatial resolution of the measured or sensed parameters.

[0050] In a still further embodiment (not shown) the sensors may be configured to sense more than one type of process parameters. In which case the first and second materials may be chosen based on the process parameters.

[0051] Further while the cladding or sheathing material is described with respect to cylindrical arrangement other structure may also be used depending on the application, for example it may be desirable to sense temperature in one direction only. In which case the segmented cladding may be non-cylindrical. In other embodiments OFS may be embedded in a matrix like structure to form a planar high-resolution sensor. In other embodiments the OFS may be embedded in mat or substrate with thermally conductive regions and thermally insulated regions. This mat may allow for a predetermined and known spacing between sensing elements in both an x and y direction. In other words, a pre-set spatial resolution.

[0052] The present matter may include sensing of pressure using the OFS as pressure sensing elements. In this case the segmented cladding may comprise alternating easily deformable material with more rigid material wherein the pressure sensor elements are located at the easily deformable material.

[0053] In an embodiment (not shown) the high spatial resolution sensor is used coupled to a sensor system for measuring one or more physical properties of an environment. In general, the system includes a light source to stimulate the OFS, a light detection module, and a signal processing module. The light detection module detects light properties resulting from interaction of sensor elements in the OFS with environment parameters being measured, the detected light properties are then processed by the signal processing module to produce a signal indicative of a physical property being measured. In another embodiment according to the present matter, data from the OFS is read by the system which includes a light source, a light modulation module, a light detection module, a signal processing module, a data acquisition module, data interpretation module, and feedback or control modules. The light source may be as a laser diode or LED, which generates light that is transmitted through OFS. The OFS interacts with the environmental process parameter being measured to change one or more of its light properties (intensity, phase, wavelength, polarization). The interaction between the light and the sensing element within the optical fiber modulates the light signal. This modulation encodes the information about the physical environmental process parameter being measured. The modulated light travels through the optical fiber to a photodetector or optical receiver, which converts the optical signal back into an electrical signal. The electrical signal is then processed by the signal processing module. The processing may include amplification, filtering, and demodulation of the electrical signal. The processed signal is then fed into a data acquisition (DAQ) module, which digitizes the signal for further analysis and storage. The digitized data may be interpreted by the data interpretation module, the interpreting process may include calibration, analysis, visualization, and storage. The interpreted data may be used to provide real-time feedback or control through the feedback or control modules.

Claims

What is claimed is:

1. A high spatial resolution sensor comprising: a plurality of sensor elements, each arranged at a respective plurality of discrete locations for sensing process parameters at the respective discrete locations; and a carrier supporting the plurality of sensor elements, the carrier including a first material for maximizing sensitivity of the sensor elements to the sensed process parameter, and a second material for minimizing coupling of the sensed parameter between the sensors wherein the first material is arranged on the carrier at each discrete location and the second material is arranged on the carrier between the discrete locations to thereby minimize coupling of the sensed process parameters between adjacent sensor elements and allow closer spacing of sensor elements.

2. The sensor of claim 1, wherein the carrier is cylindrical, and the sensor elements are optical fiber-based sensors supported along a longitudinal axis of the cylindrical carrier.

3. The sensor of claim 1, wherein the first material is a thermally conductive material, and the second material is a thermally nonconductive material.

4. The sensor of claim 1 , wherein the first material is but not limited to copper, and the second material is but not limited to polyetheretherketone (PEEK).

5. The sensor of claim 1, including multiple contiguous segments of said first and second materials.

6. The sensor of claim 1, wherein the first and second materials provide a rigid support and protective structure for the sensor elements.

7. The sensor of claim 1 , including a signal processing block for coupling signals to and from the sensor elements, to determine measurements of the process parameter being sensed.

8. The sensor of claim 1, wherein the sensed parameter is temperature.

9. The sensor of claim 1, wherein the sensed parameter is pressure.

10. A method for a high spatial resolution sensor comprising: configuring a plurality of sensor elements, each at a respective plurality of discrete locations along a sensor probe; sensing process parameters by the sensor elements at the respective discrete locations; and supporting the plurality of sensor elements on a carrier, the carrier including a first material for maximizing sensitivity of the sensor elements to the sensed process parameter, and a second material for minimizing coupling of the sensed parameter between the sensors wherein the first material is arranged on the carrier at each discrete location and the second material is arranged on the carrier between the discrete locations to thereby minimize coupling of the sensed process parameters between adjacent sensor elements and allow closer spacing of sensor elements.

11. A temperature sensing element comprising: a sensing cable configured for sensing temperature at spaced locations along the sensing cable; and a protective sheath having a segmented thermal conductor-isolator-conductor structure for minimizing thermal shunting effects between the spaced measurement locations to achieve high spatial resolution temperature sensing along the sensing cable.

12. The temperature sensing element of claim 11, wherein the sensing cable is an optical fiber cable.

13. The temperature sensing element of claim 12, wherein the temperature sensors are optical fiber sensors.

4. The temperature sensing element of claim 11 including a sensor system for measuring a physical property of an environment, the system further including a light source, a light detection module, and a signal processing module, wherein the sensing cable is coupled to the light source and wherein the light detection module detects light properties resulting from interaction of sensor elements with environment parameters being measured, the detected light properties being processed by the signal processing module to produce a signal indicative of the physical property being measured.

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