Patent Description:
Wellbores are drilled into the earth for a variety of purposes including tapping into hydrocarbon bearing formations to extract the hydrocarbons for use as fuel, lubricants, chemical production, and other purposes. These hydrocarbons are often transmitted to processing plants via pipelines. Fluidic channels such as pipelines and wellbores need to be inspected to determine issues such as leaks, blockages by deposits, or structural erosion or damage.

Most methods for monitoring the integrity of fluidic channels are intrusive, such as using pigs, overhead drones, low flying airplanes, and the like. These methods can entail considerable investments in money and time.

<CIT> discloses a method and system for assessing the condition of a pipeline in a pipeline system. The method includes generating a pressure wave in the fluid being carried along the pipeline system at a pressure wave generating location along the pipeline system and detecting pressure wave interaction signals at two closely spaced measurement locations along the pipeline. The method then includes determining a system response function for the pipeline based on the detected pressure wave interaction signals for each measurement location and characterising the pipeline based on the system response function.

<CIT> discloses a method and system for assessing the condition of a pipe carrying a fluid. The method includes the steps of generating a pressure wave in the fluid being carried along the pipe and detecting a pressure wave interaction signal resulting from an interaction of the pressure wave with a localized variation in pipe condition. The method then involves deter- mining from the timing of the pressure wave interaction signal the location of the localised variation in pipe condition and the extent of the localised variation in pipe condition based on a characteristic of the pressure wave interaction signal.

<CIT> discloses methods and systems to estimate physical dimensions of actual obstructions identified as being in a wellbore of an injection well are provided. Methods and systems include the determination of a well performance model with a simulated obstruction, using inflow performance and outflow performance relationships.

<NPL>") investigates experimentally the wave scattering effect of rough blockages in the pipeline and its impacts on the transient analysis for pipe systems. Two experimental configurations of rough blockages (hard gravels and fibrous materials) are considered to examine the wave scattering effect on transient wave propagation. The results obtained are used to validate and verify the findings of previous numerical and analytical studies. The results of this study provide fundamental understanding and profound implications to practical applications such as transient-based pipe system design and pipe blockage detection.

<CIT> discloses tube waves used to locate and characterize a solids deposit inside a fluid-filled pipe. An acoustic tube wave pulse is transmitted along the pipe. On encountering a solids deposit, the tube wave pulse is perturbed and partially reflected by changes in the boundary conditions between the fluid and the pipe to produce two deposit-modified acoustic waves. One is a perturbed wave travelling in the same direction as the tube wave pulse. The other is a reflected wave travelling in the opposite direction. One of these deposit-modified acoustic waves is received to produce an acoustic signal. Accumulated acoustic signals are processed by Fast-Fourier Transform to produce frequency-based digital data. Phase data from the frequency-based digital data is inverted to produce slowness spectrum data. Power data from the frequency-based digital data is inverted to produce attenuation spectrum data. Spectrum data is used to locate a solids deposit in the pipe. Inversion model processing of the spectrum data is used to estimate solids deposit thickness and type.

<CIT> discloses a system and method for monitoring a characteristic of an environment of an electronic device. The electronic device may include a printed circuit board and a component. A sensor is placed on the printed circuit board, and may be between the component and the board, and connects to a monitor, or detector. An end user device may be used to store, assess, display and understand the data received from the sensor through the monitor.

Implementations of the present technology will now be described, by way of example only, with reference to the attached figures, wherein:.

It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the examples described herein. However, it will be understood by those of ordinary skill in the art that the examples described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure.

Disclosed herein are systems and methods for non-intrusively determining deposits in a fluidic channel. A measured pressure profile is obtained using pressure pulse technology which is then used to iteratively improve an estimation of deposit of a fluid channel. When the error between the measured pressure profile and the modeled deposit is within a curtained predefined threshold, a final deposit is output as a function of range to show location of deposits within the fluidic channel.

In order to obtain a measured pressure profile, pressure pulses are induced in the fluidic channel. One or more sensors measure a pressure profile based on the pressure pulses reflecting off of obstructions in the fluidic channel. The measured pressure profile may be then forwarded to a data acquisition system, or a processing unit.

The data acquisition system also generates a forward model of deposits in the fluidic channel. The forward model is generated using an initial estimate of the deposits at desired grid points and data regarding the pressure pulses. Based on the forward model, a simulated pressure profile is generated. An error is calculated using the measured pressure profile and the simulated pressure profile. If the error is not within a predetermined threshold, or in other words, when the error is too high or outside of the predetermined threshold, then the inputs to the forward model are updated. The updated forward model is adjusted based on the error. With the updated forward model, another simulated pressure profile is generated, and the error is calculated. If the error is once again outside of the predetermined threshold, then updating the forward model and subsequent steps are repeated until the error is within the predetermined threshold. If the error is within the predetermined threshold, then the forward model is output, and a model of deposits in the fluidic channel is generated. Since the inputs to the forward model are updated based on the error, this method may reduce the time for processing loads and enables processing completion, for instance, by a factor of greater than <NUM>. The resolution of such an inversion scheme can also be much higher. For example, instead of the resolution being in terms of kilometers, the resolution utilizing the method can provide resolution in terms of meters.

The method can be employed in an exemplary system <NUM> shown, for example, in <FIG> illustrates a schematic diagram of a fluidic channel <NUM>. The fluidic channel <NUM> illustrated in <FIG> is a pipeline. In other examples, the fluidic channel <NUM> can be, for example, a pipeline, a wellbore, a drill string, or any channel through which fluid flows. The portion of the fluidic channel <NUM> may have any orientation or extend only in one direction or multiple directions, for example vertical or at an angle, along any axis, and may be but is not required to be horizontal as schematically depicted in <FIG>. The fluidic channel <NUM> has walls <NUM> which form an annulus <NUM> through which fluid can be contained in and flow. The fluid can be one fluid or more than one fluid. The fluid can include, for example, water or oil. The fluid can also substantially fill the entire fluidic channel <NUM>. In other examples, the fluid can partially fill the fluidic channel <NUM>. The walls <NUM> of the fluidic channel <NUM> can form a cross-sectional shape such as substantially circular, ovoid, rectangular, or any other suitable shape. The walls <NUM> of the fluidic channel <NUM> can be made of any combination of plastics or metals, suitable to withstand fluid flow without corrosion and with minimal deformation.

Within the fluidic channel <NUM>, for example along the walls <NUM>, deposits <NUM> may form. The deposits <NUM> can extend into the annulus <NUM> of the fluidic channel <NUM> any amount and in any shape and form to impede flow of the fluid. For example, in some areas, the deposits <NUM> may completely block the annulus <NUM> of the fluidic channel <NUM>. In some areas, the walls <NUM> of the fluidic channel <NUM> do not have any deposits <NUM> formed thereon. In yet other areas, the deposits <NUM> only partly block the annulus <NUM>. The deposits <NUM> can be, for example, wax deposits, clay deposits, or any other possible deposits that can adhere to the walls <NUM> of the fluidic channel <NUM> such that the fluid flow is at least partly impeded.

To obtain the measured profile, and inspect the fluidic channel <NUM> in a nonintrusive manner, at least one pressure pulse, such as a water-hammer pulse, can be induced. To induce the pressure pulses, a device <NUM> can be used. The device <NUM> can create a pressure pulse that travels through the fluidic channel <NUM> at the local speed of sound in the medium. An example of a device <NUM> is used in the PressurePulse™ Service by Halliburton Energy Services, Inc. The device <NUM> is not a permanent fixture or attachment. As such, the device <NUM> can be disposed in the fluidic channel <NUM> or coupled with the fluidic channel <NUM> only when needed to create pressure pulses. In other examples, the device <NUM> can be a permanent fixture in the fluidic channel <NUM>. The device <NUM> can be, for example, a valve. The device <NUM> can create the pressure pulse by opening and closing the valve. When the valve is shut, a pressure pulse is generated that travels upstream of the valve. The device <NUM> can be electrically programmed, such that different pressures can be induced based on the open and close sequences. The quicker the valve is opened and closed, the greater, or sharper, the pressure pulse.

As the pressure pulse travels along the fluidic channel <NUM>, any encountered obstructions or deposits <NUM> generate a reflected signal which is received back at the device <NUM>. The system <NUM> includes a sensor <NUM> to receive the reflected pressure pulse signals. The sensor <NUM> can be a known distance from the device <NUM>. The sensor <NUM> can be a pressure transducer. In other examples, the sensor <NUM> can be any suitable sensor that measures pressure or stress of the fluid, for example a string gauge or an optical fiber transducer. The reflected signals are then passed through a transmission system <NUM> to a data acquisition system <NUM> to be interpreted to map out and quantify any deposits <NUM> in the fluidic channel <NUM>. The data acquisition system <NUM> can be at the surface, within a vehicle such as a submarine, or any other suitable location such that the data can be interpreted by an operator. The data acquisition system <NUM> can include a non-transitory computer readable storage medium. The non-transitory computer readable storage medium includes at least one processor and stores instructions executable by the at least one processor. The transmission system <NUM> can be wireline, optical fiber, wirelessly such as through the cloud or Bluetooth, or any other suitable method to transmit data.

Referring to <FIG>, a flowchart is presented in accordance with an example embodiment. The method <NUM> is provided by way of example, as there are a variety of ways to carry out the method. The method <NUM> described below can be carried out using the configurations illustrated in <FIG>, for example, and various elements of these figures are referenced in explaining example method <NUM>. Each block shown in <FIG> represents one or more processes, methods or subroutines, carried out in the example method <NUM>. Furthermore, the illustrated order of blocks is illustrative only and the order of the blocks can change according to the present disclosure. Additional blocks may be added or fewer blocks may be utilized, without departing from this disclosure. The example method <NUM> can begin at block <NUM>.

At block <NUM>, a pressure pulse is induced in a fluidic channel as described above. One or more pressure pulses can be induced. For example, a sequence of pressure pulses of differing sharpness can be induced. In other examples, the pressure pulses may all have the same sharpness. In yet other examples, only one pressure pulse is induced. The pressure pulse is induced by a device which can be a valve. By opening and closing the valve, a pressure pulse is induced. The faster the valve is closed, the sharper the pressure pulse. The pressure pulse travels upstream in the fluidic channel and reflects off of any obstructions such as deposits in the fluidic channel.

At block <NUM>, the pressure fluctuations are then recorded by one or more sensors. The data is then transmitted to a data acquisition system to interpret the data.

At block <NUM>, a measured pressure profile is obtained. The measured pressure profile, as shown in <FIG>, is provided as a diagram <NUM> of pressure versus time. Section <NUM> of the diagram <NUM> illustrates the pressure spike created by the opening and closing of the valve. The quicker the valve is closed, the sharper the pressure spike. Section <NUM> of the diagram <NUM> illustrates pressure fluctuations which correspond to obstructions such as deposits in the fluidic channel.

Referring back to <FIG>, at block <NUM>, the deposits in the fluidic channel are modeled. The modeling can be performed by a data acquisition system which includes a non-transitory computer readable storage medium. The non-transitory computer readable storage medium includes at least one processor and stores instructions executable by the at least one processor. To model the deposits, a baseline simulation, at block <NUM>, is used. The baseline simulation is a simulation of the fluidic channel if there are no deposits. The baseline simulation can be calculated using hydrodynamic equations by knowing information about the fluidic channel such as the fluid, the diameter and shape, the pressure pulse that would be created by the device, among other known data. From the baseline simulation, a simulated pressure profile, as illustrated in <FIG>, can be created. As shown in <FIG>, similar to the measured pressure profile in <FIG>, a simulated pressure profile is provided as a diagram <NUM> of pressure versus time. Section <NUM> of the diagram <NUM> illustrates the pressure spike created by the opening and closing of the valve. However, different than the measured pressure profile of <FIG>, there are no fluctuations in the pressure, as the simulated pressure profile is based on the baseline simulation which assumes that there are no deposits in the fluidic channel. If there are known deposits or obstructions which would cause fluctuations in the fluidic channel, those may be shown in the simulated pressure profile.

The model of the deposits is then created by comparing the simulated pressure profile with the measured pressure profile and adjusting the simulated pressure profile until the simulated pressure profile and the measured pressure profile substantially match. To substantially match, the error between the simulated pressure profile and the measured pressure profile must fall within a predetermined threshold. Modeling the deposits will be described in further detail in <FIG> below.

Referring back to <FIG>, at block <NUM>, if the simulated pressure profile and the measured pressure profile are substantially matching, a model of deposits in the fluidic channel is generated.

Referring to <FIG>, a flowchart is presented in accordance with an example embodiment. The method <NUM> is provided by way of example, as there are a variety of ways to carry out the method. The method <NUM> described below can be carried out using the configurations illustrated in <FIG>, for example, and various elements of these figures are referenced in explaining example method <NUM>. Each block shown in <FIG> represents one or more processes, methods or subroutines, carried out in the example method <NUM>. Furthermore, the illustrated order of blocks is illustrative only and the order of the blocks can change according to the present disclosure. Additional blocks may be added or fewer blocks may be utilized, without departing from this disclosure. The example method <NUM> can be implemented using data acquisition system which includes a non-transitory computer readable storage medium. The non-transitory computer readable storage medium includes at least one processor and stores instructions executable by the at least one processor to implement the example method <NUM>. The example method <NUM> can begin at block <NUM>.

At block <NUM>, a forward model of a fluidic channel is generated. The forward model is generated using water-hammer equations. The forward model is based on the baseline simulation. The forward model incorporates an initial guess at deposits, or estimated deposits, at desired grid points. The grid points may be <NUM> meter, <NUM> meters, <NUM> meters, <NUM> meters, or any desired resolution. The initial guess at deposits includes, for example, any known deposits. The known deposits may be known because of previous experience or known obstructions in the fluidic channel. The initial guess at deposits can also be set at <NUM>, which provides that no deposits are known.

The forward model also incorporates a valve closing profile. The valve closing profile includes how the device created a pressure pulse, for example, how fast the valve was closed and/or the sequences of opening and closing the valve. As such, the valve closing profile includes the known information of the pressure pulses and known reflections that would occur from any known deposits or obstructions in the fluidic channel.

At block <NUM>, a simulated pressure profile is generated from the forward model. The simulated pressure profile is a diagram of pressure versus time and reflects the initial pressure spike from the device creating the pressure pulse and pressure fluctuations from the pressure pulse reflecting off of estimated obstructions in the fluidic channels such as deposits.

At block <NUM>, an error is calculated. The error indicates an amount that the simulated pressure profile does not correspond to the measured pressure profile. To calculate the error, the measured pressure profile from the at least one sensor is utilized. The error is calculated based on the difference between the measured pressure profile and the simulated pressure profile. The error can be calculated using the equation:<MAT>.

At block <NUM>, the error is compared with a predetermined threshold.

If the error is not within the predetermined threshold, the forward model is updated at block <NUM>. The updated inputs (for example the deposit as a function of range) to the forward model can be calculated using the equation:<MAT> As such, the forward model is adjusted based on the error. The adjustable factor α has a sign which is the same as the sign of the difference between the measured pressure profile and the simulated pressure profile. The value of the adjustable factor α is empirically tested. For example, the first iteration of the adjustable factor α may be the largest number that is not numerically unstable. The value of the adjustable factor α can be dynamically adjusted depending on the magnitude of the error to ensure a slower rate of convergence when the simulated pressure profile is close to the measured pressure profile, or when the error begins to grow rather than reduce with the number of iterations. The steps of generating a forward model <NUM>, generating a simulated pressure profile <NUM>, calculating an error <NUM>, determining whether the error is within, or less than, a predetermined error <NUM>, and updating the forward model <NUM> are repeated until the error is within the predetermined threshold.

For example, the first iteration of the adjustable factor α can be <NUM>. If the error is not within the predetermined threshold, then in the next iteration, the adjustable factor α may be set at <NUM>. If, once again, the error is not within the predetermined threshold, in the following iteration, the adjustable factor α may be set at <NUM>. In each iteration, the adjustable factor α is changed to be a higher or a lower value based on the change of the error until the error is less than the predetermined threshold.

By basing the adjustments to the forward model on the error, the processing time can be reduced, for example, from <NUM> to <NUM> hours to <NUM> to <NUM> minutes on average.

If the error is within the predetermined threshold, then at block <NUM>, the forward model is outputted.

At block <NUM>, a model of deposits in the fluidic channel is then generated and outputted. <FIG> illustrates an exemplary diagram <NUM> of a model of deposits in the fluidic channel. The exemplary diagram <NUM> provides for amount of deposits versus distance from the device and/or sensor. As illustrated in <FIG>, the model of deposits in the fluidic channel provides for a visualization of the amount of obstruction that the deposit creates at each point of the fluidic channel.

Claim 1:
A method for non-intrusively determining deposits (<NUM>) in a fluidic channel (<NUM>), the method comprising:
obtaining, from one or more sensors (<NUM>), a measured pressure profile based on at least one pressure pulse induced in a fluidic channel;
generating (<NUM>) a forward model of deposits in the fluidic channel;
generating (<NUM>), using the forward model, a simulated pressure profile;
calculating (<NUM>), using the measured pressure profile and the simulated pressure profile, an error;
updating (<NUM>), when the error is outside a predetermined threshold, the forward model including updated inputs calculated using updated deposit = the deposit + α * sqrt(the error), wherein α is an adjustable factor, the value of which is empirically tested;
repeating, until the error is within the predetermined threshold, the steps of generating the forward model, generating the simulated pressure profile, calculating the error and updating the forward model;
adjusting the updated forward model based on the error;
outputting (<NUM>), when the error is within the predetermined threshold, the forward model;
generating (<NUM>), using the forward model, an estimate of deposits in the fluidic channel; and
outputting the estimate of deposits in the fluidic channel.