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Excessive liquid carryover in T-junction presents a serious operational issue in offshore production platform. Slug flow and diameter ratio of T-junction are considered as two major factors causing liquid carryover. Regular and reduced T-junction are being used as partial phase separator but their efficiency is low. Converging T-junction with two distinct diameters (primary and secondary) in branch arm is used to improve the phase separation efficiency. The motivation is to combine specific feature of regular and reduced T-junction to increase separation efficiency of existing T-junction without involving too much operational workover. The purpose of this paper is to numerically evaluate the separation efficiency of a converging T-junction design. The present model and its methodology was validated with in-house experimental data for 3 inches diameter flow loop.

The slug flow regime was simulated using incompressible Eulerian mixture model coupled with volume of fluid method to capture the dynamic gas-liquid interface.

The analyses concluded that T-junction with primary-secondary branch arm diameters combination of 1.0-0.5 and 0.67-0.40 managed to achieve 95 per cent separation efficiency. The research also confirmed that over reduction of T-junction secondary diameter ratio below 0.2 will lead to decrease in separation efficiency.

The present research is limit to air/water two-phase flow but the general results should be applicable for wider application.

The proposed design limited excessive workover and installation for current and existing T-junction. Hence, cutting down installation cost while improving the separation efficiency.

The present research resulted in higher separation efficiency, cutting down production down time and lead to operational cost saving.

The present research proposes an original and new T-junction design that can increase phase separation efficiency to over 90 per cent. The finding also confirmed that there is a limitation whereby smaller diameter ratio T-junction does not always resulted in better separation.

Offshore industries encounter severe production downtime due to high liquid carryovers in the T-junction. The diameter ratio and flow regime can significantly affect the excess liquid carryovers. Unfortunately, regular and reduce T-junctions have low separation efficiencies. Ansys as a commercial computational fluid dynamics (CFD) software was used to model and numerically inspect a novel diverging T-junction design. The purpose of diverging T-junction is to merge the specific characteristics of regular and reduced T-junctions, ultimately increasing separation efficiency. The purpose of this study is to numerically compute the separation efficiency for five distinct diverging T-junctions for eight different velocity ratios. The results were compared to regular and converging T-junctions.

Air-water slug flow was simulated with the help of the volume of the fluid model, coupled with the K-epsilon turbulence model to track liquid-gas interfaces.

The results of this study indicated that T-junctions with upstream and downstream diameter ratio combinations of 0.8–1 and 0.5–1 achieved separation efficiency of 96% and 94.5%, respectively. These two diverging T-junctions had significantly higher separation efficiencies when compared to regular and converging T-junctions. Results also revealed that over-reduction of upstream and downstream diameter ratios below 0.5 and 1, respectively, lead to declination in separation efficiency.

The present study is constrained for air and water as working fluids. Nevertheless, the results apply to other applications as well.

The proposed T-junction is intended to reduce excessive liquid carryovers and frequent plant shutdowns. Thus, lowering operational costs and enhancing separation efficiency.

Higher separation efficiency achieved by using diverging T-junction enabled reduced production downtimes and resulted in lower maintenance costs.

A novel T-junction design was proposed in this study with a separation efficiency of higher than 90%. High separation efficiency eliminates loss of time during shutdowns and lowers maintenance costs. Furthermore, limitations of this study were also addressed as the lower upstream and downstream diameter ratio does not always enhance separation efficiency.

In plethora of petroleum, chemical and heat transfer applications, T-junction is often used to partially separate gas from other fluids, to reduce work burden on other separating equipment. The abundance of liquid carryovers from the T-junction side arm is the cause of production downtime in terms of frequent tripping of downstream equipment train. Literature review revealed that regular and reduced T-junctions either have high peak liquid carryovers (PLCs) or the liquid appears early in the side arm [liquid carryover threshold (LCT)]. The purpose of this study is to harvest the useful features of regular and reduced T-junction and analyze diverging T-junction having upstream and downstream pipes.

Volume of fluid as a multiphase model, available in ANSYS Fluent, was used to simulate air–water slug flow in five diverging T-junctions for eight distinct velocity ratios. PLCs and LCT were chosen as key performance indices.

The results indicated that T (0.5–1) and (0.8–1) performed better as low liquid carryovers and high LCT were achieved having separation efficiencies of 96% and 94.5%, respectively. These two diverging T-junctions had significantly lower PLCs and high LCT when compared to other three T-junctions. Results showed that the sudden reduction in the side arm diameter results in high liquid carryovers and lower LCT. Low water and air superficial velocities tend to have low PLC and high LCT.

This study involved working fluids air and water but applies to other types of fluids as well.

The novel T-junction design introduced in this study has significantly higher LCT and lower PLC. This is an indication of higher phase separation performance as compared to other types of T-junctions. Because of lower liquid take-offs, there will be less frequent downstream equipment tripping resulting in lower maintenance costs. Empirical correlations presented in this study can predict fraction of gas and liquid in the side arm without having to repeat the experiment.

Maintenance costs and production downtime can be significantly reduced with the implication of diverging T-junction design.

The presented study revealed that the diameter ratio has a significant impact on PLC and LCT. It can be concluded that novel T-junction designs, T2 and T3, achieved high phase separation; therefore, it is favorable to use in the industry. Furthermore, a few limitations in terms of diameter ratio are also discussed in detail.

The purpose of this paper is to present a practical way to create three kinds of double emulsions such as double emulsion, double-component double emulsion and viscoelastic double emulsion.

A hierarchical T-junction microfluidic device is selected to simulate this phenomenon. A system of the three-phase flows consists of the inner, middle and outer phases were simulated by the direct numerical simulation (DNS) method. The dripping regime is considered for the droplet formation in both T-junctions. The adaptive mesh refinement technique is used to simulate the droplet formation and determine the interface rupture.

The one-step and two-step encapsulation are used to create the double emulsion and the viscoelastic double emulsion, respectively. In both T-junctions, droplets are created by the balance of three parameters which are instability, viscous drag and pressure buildup. The one-step formation of double emulsion is presented for encapsulates the viscoelastic fluid.

The simulated hierarchical microchannel shows some desirable features for creating the complex compounds. The encapsulation process is simulated in micro-scale that is useful for drug delivery applications.

The narrow‐wall inclined‐slot coupling between rectangular waveguides from an H‐plane T‐junction, is numerically analysed, for the first time, via a 3D generalised locally conformed FDTD technique. The structure is excited by a combined pulsed modulated TE_mn mode scheme which enables the imposition of higher‐order ABCs or advanced PMLs very close to the slot, thus achieving significant reduction of the computational demands. Numerical results, which are shown to be in very good agreement with those obtained by independent scientific research, indicate that the proposed technique can sufficiently handle this class of problems.

Theoretical investigations have been performed on slowly propagating cracks in T‐junctions and cross bars using computer procedures developed to analyse the amount and direction of crack growth using automatic mesh modification and the finite element stress analysis program, BERSAFE. The procedures may be used in a linear or non‐linear material. The crack growth for the linear elastic case is calculated to be in the direction of the maximum energy release rate. For the non‐linear case, the direction is taken to be that of Jwi. These procedures have been applied to fatigue crack growth calculations in this paper.

This paper aims to present the design, fabrication and analysis of a wideband, enhanced gain 1 × 2 patch antenna array with a simple profile structure to meet the desired antenna traits, such as wide bandwidth, high gain and directional patterns expected for the upcoming fifth-generation (5G) wireless applications in the millimeter wave band. To enhance these parameters (bandwidth and gain), a new antenna geometry by using a T-junction power divider is presented.

The theory behind this paper is connected with advancements in the 5G communications related to antennas. The methodology used in this work is to design a high gain array antenna and to identify the best possible power divider to deliver the power in an optimized way. The design methodology adopts several steps like the selection of proper substrate material as per the design specification, size of the antenna as per the frequency of operation and application-specific environment condition. The simulation has been performed on the designed antenna in the electromagnetic simulation tool (high-frequency structure simulator [HFSS]), and optimization has been done with parametric analysis, and then the final array antenna model is proposed. The proposed array contains 2-patch elements excited by one port adapted to 50 Ω through a T-junction power divider. The 1 × 2 array configuration with the suggested geometry helps to improve the overall gain of the antenna, and the implementation of the T-junction power divider provides enhanced bandwidth. The proposed array designed using a 1.6 mm thick flame retardant substrate occupies a compact area of 14 × 12.14 mm².

The prototype of the array antenna is fabricated and measured to validate the design concept. A good agreement has been reached between the measured and simulated antenna parameters. The measured results confirm its wideband and high gain characteristics, covering 24.77–28.80 GHz for S₁₁= –10 dB with a peak gain of about 15.16 dB at 27.65 GHz.

The proposed antenna covers the bandwidth requirements of the 26 GHz n258 band (24.25–27.50 GHz) to be deployed in the UK and Europe. The suggested antenna structure also covers the federal communications commission (FCC)-regulated 28 GHz n261 band (27.5–28.35 GHz) to be deployed in America and Canada. The low profile, compact size, simple structure, wide bandwidth, high gain and desired directional radiation patterns confirm the applicability of the suggested array antenna for the upcoming 5 G wireless systems.

The purpose of this paper is to describe design and development of a pole climbing robot (PCR) for inspection of industrial size pipelines. Nowadays, non‐destructive testing (NDT) methods are performed by dextrous technicians across high‐level pipes, frequently carrying dangerous chemicals. This paper reports development of a PCR that can perform in situ manipulation for NDT tests.

Introduces a PCR including a novel four‐degrees of freedom climbing serial mechanism with the nearly optimal workspace and weight, unique V‐shaped grippers and a fast rotational mechanism around the pole axis. Simplicity, safety, minimum weight, and manipulability were concerned in the design process.

The developed prototype proved possibility of application of PCRs for NDT inspection on elevated structures. Design and development of PCRs which are able to pass bends and T‐junctions faces much more difficulties than those which should climb from a straight pole.

The robot is successfully tested on an industrial size structure (exterior diameter of 219 mm) with bends and T‐junctions.

Design and development of a novel pole climbing and manipulating robot for inspection of industrial size pipelines. The robot is able to pass bends and T‐junctions. The V‐shaped grippers offer many advantages including safety and tolerance to power failure. After grasping the structure, in case of power failure in any of the grippers' motors, the robot does not slip on the structure. The Z‐axis rotational mechanism provides fast navigation around the pole which is not possible with the traditional serial articulated arms.

The structure‐borne sound generated by power equipment can be isolated effectively through vibration absorber under hull base structures. The practical vibration isolation performance is limited due to the weight, size and cost. The dramatic attenuating wave propagation characteristic of hull base without adding weight is essential to the vessel acoustic stealth.

The characteristics of vibration wave propagated from typical shape base link structures have been investigated according to impedance mismatch and wave conversion in non‐homogeneous structure. The hull base is simplified to three degrees of freedom damped system through the mechanical impedance method. The influence of blocking mass weight, as well as location properties to the base vibration isolation performance have been discussed. Furthermore, the structure‐borne sound design of a typical hull base is carried out.

The impedance mismatch of the hull base is further increased by the comprehensive use of high transmission loss base link structures, blocking mass as well as damping layer. The effectiveness of structure‐borne sound design is verified through numerical calculation together with underwater model test. The test data show that the noise has been reduced larger than 3 dB.

The paper describes what is believed to be the first application of the high transmission loss base in hull structures based on the literature survey. The method of structure‐borne sound design of a typical hull base can be applied in different types of vessels.