A New Condition Monitoring System Improves the Reliability of the RCD Element During the MPD Jobs

Managed pressure drilling (MPD) is a technology that allows for precise wellbore pressure control, especially in formations of uncertain geomechanical properties (in specific: Fracture pressure and pore pressure gradients). The rotating control device (RCD) is the backbone to the MPD equipment. A new condition monitoring system was developed to improve the reliability of the RCD elements and to eliminate its catastrophic failures during MPD jobs. The new method to increase the reliability of an RCD is based on understanding and quantifying the factors affecting the lifetime of the RCD components. The condition monitoring system was designed to be attached onto the RCD and collect data from an array of sensors during the MPD jobs. Sensors are measuring: vibrations, acoustic emissions, rotation, pipe movement, temperatures and contamination level in the coolant fluid. System is capable to display the measurements in the real time to the operator, giving early warnings to take actions in order to prevent catastrophic failures of the RCD during the job. Data is also recorded to allow further processing and analysis using ML and AI techniques. The authors will discuss in detail the background and rationale to the new technology, including a review of the condition monitoring system, its elements, and functionality. The system design and intended operation will be explained including, sensors and data collection points in the condition monitoring process. No catastrophic failures of the RCD were encountered when the RCD condition monitoring system was installed and running in the field up to date. The measurements collected from the array of sensors and presented in the real time to the MPD operators, allows to monitor changes in condition of the critical RCD elements. From the system design, sensor type, and frequency of data inputs, it was concluded that the quantification of some parameters affecting the lifetime of RCD could be successfully performed in post analysis, using advanced AI techniques. This condition monitoring system can optimize the MPD operations, making MPD jobs safer and reducing the Non Productive Time. The novelty of this condition monitoring system is in the approach of measuring and displaying critical values to the operator during the job and possibility to quantification of the factors affecting the RCD elements lifetime.

UNIDIRECTIONAL COUPLED FINITE ELEMENT SIMULATION OF THERMOELASTIC TCP-DISPLACEMENT THROUGH MILLING PROCESS CAUSED HEAT LOAD

The paper presents a numerical simulation of thermal induced tool displacement during milling oper-ation. An unidirectional finite element model is developed which consists of two sections. A CFX model and a thermal transient model. With the aid of CFX module, the conjugated heat transfer be-tween milling tool and coolant fluid is described. The result of these efforts is the body temperature field of the end mill cutter due to thermal load, which is the thermal fingerprint of the cutting process. Subsequently the calculated body temperature field is linked with a transient-structural module to cal-culate the resulting thermal elastic displacement of the milling cutter. The thermo-elastic displace-ment of the tool is determined by examining a pilot node at the tip of the end mill, whose displace-ment is calculated in relation to the global coordinate system of the model.

Heat Transfer Enhancement in Subchannel Geometry of Pressurized Water Reactor Using Water-Based Yttrium Oxide Nanofluid

Simulation of Computational Fluid Dynamic is applied to present the thermal performance of water-based Yttrium oxide nanofluid in subchannel of pressurized water reactor (PWR) system. Thermal hydraulic aspect such as pressure drop and heat transfer are estimated in typical conditions of pressurized water with flow rates ranged (20×103≤Re≤80×103) using fresh water (0 %vol.) and different volume fraction of water-Yttrium oxide nanofluid (2 and 4% vol.) as coolant fluid. Results were obtained and compared with correlations of single-phase pressure drop and convective heat transfer for the case of fully developed turbulent flow. The addition of Yttrium oxide nanoparticles to the coolant fluid in pressurized water reactor led to increase in convective heat transfer coefficient and pressure drop. Increasing the nanoparticle volume fraction of (2 and 4% vol.) causing an increase in the average Nu by 3.46% and 7.61%, respectively. The CFD model established in ANSYS software was validated by comparing the pressure drop of CFD results with Blasius correlation and Nu with Ma¨ıga et al. correlation and gave a good agreement.

Simulation of a Plate Heat Exchanger Operating with Nanofluid Coolant Using CFD

The use of nanofluids as coolant fluid in a plate heat exchanger (PHE) was investigated by conducting 3D CFD (Computational Fluid Dynamics) simulations. Al2O3/water nanofluid with volume concentrations of 2%, 3% and 4% was used as coolant fluid and water as hot fluid. In addition, the effects of corrugation angle of the plates were analyzed by varying them between 0° and 60°. Validation was performed by using heat transfer coefficients experimentally obtained in a previous study. Results show that the use of nanofluids in higher concentrations improves the performance of the PHE’s parameters. The angles of 30° and 60° between the plates reduce pressure drop and reflux regions improving the heat exchange. The variations of the nanofluid flow must take into account the proper pressure drop for the process where is PHE is employed because the increased flow rate results in a significant increase in the pressure drop. In general, this work has potential to be used for enhancing the design of PHEs.

Statistics and Computational Fluid Dynamics Analyses of the Experimentally Confirmed Thermal Behavior of Self-designed Internally Cooled Smart Cutting Tool

When compared with dry machining, using traditional cutting fluids has some weaknesses such as environmental pollution, high machining costs and harmful effects on human health. Internally cooled cutting tools (ICCT) have been a promising, sustainable, health-friendly and green technologies for turning applications. However, the effects of different types of internal coolant fluids on insert tip temperature (Ttip) have not been investigated for ICCTs. Within effective cooling, machining quality of metallic materials and tool life can improve. Therefore, a conjugate heat transfer (CHT) model for a self-designed internally cooled smart cutting tool (ICSCT) was set. The CHT simulation was experimentally confirmed using pure water. After that, the effects of flow velocity (Vf), inlet temperature of the coolant fluid (Tinlet) alongside different types of glycol-based heat transfer fluids (including pure water) on Ttip were statistically evaluated by the Taguchi method and analysis of the variance (ANOVA). It was found that the most effective factor was the Tinlet at a contribution ratio level of 88.32%. Additionally, Vf and the type of heat transfer fluid were found to be significant according to statistics. Hence, since no external coolant is used, the designed smart tool can be counted as being environmentally friendly and health friendly. In conclusion, the glycol-based fluids can be a better choice for internally cooled tool designs owing to their superior features, e.g., corrosion prevention, nontoxicity and stable heat transfer capability at lower temperatures compared to pure water although pure water has better thermal properties than the glycol-based fluids.

Redesign of the TG20 Heavy-Duty Gas Turbine to Increase Turbine Inlet Temperature and Global Efficiency

The even more stringent limitations set by the European Commission on pollutant emissions are forcing gas turbine manufacturers towards the redesign of the most important components to increase efficiency and specific power. Current trends in gas turbine design include an increased attention to the design of cooling systems and enhanced best practices for the study of components interaction. At the same time, the recent crisis suffered by the oil and gas industry reduced the interest in brand new gas turbines, thus increasing the service market. Therefore, original equipment manufacturers would rather propose the replacement of specific components within the gas turbine plant during its maintenance with compatible elements that are likely to guarantee increased performance and longer residual lifetime at a more desirable nominal working point. In the present activity the cooling system of the TG20 heavy-duty gas turbine has been redesigned to increase the turbine inlet temperature while contemporaneously reducing the total amount of coolant mass-flow. Specifically, the cooling scheme of the rotating blade of the first turbine row has been reviewed at the Department of Energy (DENERG) of Politecnico di Torino in cooperation with EthosEnergy Italia S.p.a.. The paper presents a new design, which, starting from the original solution featuring fifteen smooth pipes, adopts an improved geometry characterized by the presence of turbulators. The activity has been carried out using Computational Fluid Dynamics (CFD) for the coolant/blade interaction and one-dimensional models developed at EthosEnergy for the redistribution of the cooling flows in the cavities. The mutual effects between the coolant fluid and the blade are analyzed using a Conjugate Heat Transfer (CHT) approach with Star-CCM+. The validation of the computational approach has been performed exploiting the experimental data available for the NASA C3X test case. The TG20 rotating blade of the first turbine row has been analyzed considering the two different coolant configurations. The impact of the main flow on the thermal field has initially been included by imposing a temperature field on the blade surface. The latter field has in turn been obtained by means of a separate computation for the solid only. Full CHT simulations has hence been performed, thus quantifying the accuracy of the proposed approach. The obtained results are discussed in terms of thermo-fluid-dynamic effects.

Thermal Analysis and Optimization of Nano Coated Radiator Tubes Using Computational Fluid Dynamics and Taguchi Method

Automotive heat removal levels are of high importance for maximizing fuel consumption. Current radiator designs are constrained by air-side impedance, and a large front field must meet the cooling requirements. The enormous demand for powerful engines in smaller hood areas has caused a lack of heat dissipation in the vehicle radiators. As a prediction, exceptional radiators are modest enough to understand coolness and demonstrate great sensitivity to cooling capacity. The working parameters of the nano-coated tubes are studied using Computational Fluid Dynamics (CFD) and Taguchi methods in this article. The CFD and Taguchi methods are used for the design of experiments to analyse the impact of nano-coated radiator parameters and the parameters having a significant impact on the efficiency of the radiator. The CFD and Taguchi methodology studies show that all of the above-mentioned parameters contribute equally to the rate of heat transfer, effectiveness, and overall heat transfer coefficient of the nanocoated radiator tubes. Experimental findings are examined to assess the adequacy of the proposed method. In this study, the coolant fluid was transmitted at three different mass flow rates, at three different coating thicknesses, and coated on the top surface of the radiator tubes. Thermal analysis is performed for three temperatures as heat input conditioning for CFD. The most important parameter for nanocoated radiator tubes is the orthogonal array, followed by the Signal-to-Noise Ratio (SNRA) and the variance analysis (ANOVA). A proper orthogonal array is then selected and tests are carried out. The findings of ANOVA showed 95% confidence and were confirmed in the most significant parameters. The optimal values of the parameters are obtained with the help of the graphs.

Turbulent Flow Characteristics in a Blocked Exterior Subchannel of a Helically Wrapped Rod Bundle

Liquid metal fast reactor using sodium as a coolant typically utilize a tightly packed triangular lattice of fuel pins enclosed in a hexagonal duct. During the reactor operation, partial or total flow blockage of coolant channels, may occur at different spatial locations within the fuel assembly, due to potential isolated or combined causes, including collection and accumulation of debris, and cladding deformation. Previous studies have shown that the flow characteristics within the wire-wrapped fuel assembly, i.e., including the interior and exterior subchannels, are very complicated and strongly influenced the flow and heat transfer phenomena between the coolant fluid and fuel rods. It is important to understand and characterize the effects of channel blockage to the flow mixing characteristics in the exterior sub-channels (or bypass channels) of the wire-wrapped fuel bundle. Texas A&M University has conducted isothermal flow experiments in a wire-wrapped 61-pin hexagonal fuel bundle to support the research on advanced nuclear fuel development sponsored by the US Department of Energy (DOE). The experimental facility employs matched-index-of-refraction (MIR) techniques and laser diagnostic velocity measurement techniques. In this article, we present the time-resolved particle image velocime-try (TR-PIV) measurements to characterize turbulent flow characteristics in the exterior subchannels of the wire-wrapped fuel bundle, under the presence of a localized total blockage of one of the exterior subchannels. From the obtained TR-PIV velocity fields, turbulent flow characteristics including mean velocity, root-mean-square fluctuating velocity, and Reynold stress, are computed and presented. In addition, spectral analysis to the turbulent velocity fields is performed to investigate the characteristic flow frequencies associated to different flow conditions with the presence of the blockage. Finally, proper orthogonal decomposition (POD) analysis is performed to the velocity snapshots to reveal the dominant flow structures that play important roles in the flow dynamics and heat transfers of the fuel bundle.

3-D Multi-Tubular Reactor Model Development for the Oxidative Dehydrogenation of Butene to 1,3-Butadiene

The oxidative dehydrogenation (ODH) of butene has been recently developed as a viable alternative for the synthesis of 1,3-butadiene due to its advantages over other conventional methods. Various catalytic reactors for this process have been previously studied, albeit with a focus on lab-scale design. In this study, a multi-tubular reactor model for the butadiene synthesis via ODH of butene was developed using computational fluid dynamics (CFD). For this, the 3D multi-tubular model, which combines complex reaction kinetics with a shell-side coolant fluid over a series of individual reactor tubes, was generated using OpenFOAM®. Then, the developed model was validated and analyzed with the experimental results, which gave a maximum error of 7.5%. Finally, parametric studies were conducted to evaluate the effect of thermodynamic conditions (isothermal, non-isothermal and adiabatic), feed temperature, and gas velocity on reactor performance. The results showed the formation of a hotspot at the reactor exit, which necessitates an efficient temperature control at that section of the reactor. It was also found that as the temperature increased, the conversion and yield increased whilst the selectivity decreased. The converse was found for increasing velocities.

Design, Modeling, and Experimental Investigation of Active Water Cooling Concentrating Photovoltaic System

This work presents performance study of a concentrating photovoltaic/thermal (CPV/T) collector and its efficiency to produce electric and thermal power under different operating conditions. The study covers a detailed description of flat photovoltaic/thermal (PV/T) and CPV/T systems using water as a cooling working fluid, numerical model analysis, and qualitative evaluation of thermal and electrical output. The aim of this study was to achieve higher efficiency of the photovoltaic (PV) system while reducing the cost of generating power. Concentrating photovoltaic (CPV) cells with low-cost reflectors were used to enhance the efficiency of the PV system and simultaneously reduce the cost of electricity generation. For this purpose, a linear Fresnel flat mirror (LFFM) integrated with a PV system was used for low-concentration PV cells (LCPV). To achieve the maximum benefit, water as a coolant fluid was used to study the ability of actively cooling PV cells, since the electrical power of the CPV system is significantly affected by the temperature of the PV cells. This system was characterized over the traditional PV systems via producing more electrical energy due to concentrating the solar radiation as well as cooling the PV modules and at the same time producing thermal energy that can be used in domestic applications. During the analysis of the results of the proposed system, it was found that the maximum electrical and thermal energy obtained were 170 W and 580 W, respectively, under solar concentration ratio 3 and the flow rate of the cooling water 1 kg/min. A good agreement between the theoretical and experimental results was confirmed.