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Owing to the injection of gas in the CERN LHC accelerator beampipe through the System for Measuring Overlap with Gas (SMOG), the LHCb experiment has been pioneering since 2015 fixed-target physics at the highest energy ever reached. Within the upgrade of the experiment, a confinement cell for the gas, SMOG2, and a new gas injection system were installed. This dedicated setup opens unique possibilities for extensive measurements for heavyion, hadron, spin and astroparticle physics. In this contribution, the SMOG2 system is presented, focussing on its validation and first outcome as obtained from the exploitation of the proton-gas data collected in 2022. [ABSTRACT FROM AUTHOR]

Oil wells can naturally produce reservoir fluids to the surface. Over time, the reservoir pressure decreased due to the consequences of producing fluid into the surface. This can result in the well being unable to produce naturally and have to use the artificial lift method. The continuous gas lift method was chosen by considering the availability of a compressor, gas injection source, gas-oil ratio, oil gravity, and overcoming the corrosion problems, sand, and gas production. The continuous gas lift design was carried out in three wells: the F-29 Well, I-10 Well, and A-04 Well. Reducing the wellhead pressure is an option to increase the production of the gas lift system. In the design of the continuous gas lift method, the well has not been able to produce oil according to the target of 70% AOF (absolute open flow) even though the wellhead pressure is lowered to 60 psi, but it showed that this method can increase production significantly. However, there must be further economic studies to do this, considering that the F-29 Well, I-10 Well, and A-04 Well have low reservoir pressure and relatively high water cut. After the reservoir pressure decreases, continuous gas lift is changed to intermittent gas lift because producing a large amount of oil at very low reservoir pressure with a large injection flow rate is considered less efficient. The intermittent gas lift is designed by changing the orifice into a PPO (production pressure operating) valve to inject gas with a particular cycle. [ABSTRACT FROM AUTHOR]

This study uses solid refused derived fuel (SRF) from municipal waste in a dual-reactor fluidized bed (DRFB) for the gasification process. Gasification which separates the process of endothermic and exothermic reactions is the focus of the development of gasification technology today. In addition to optimizing fuel conversion, the DRFB system can also recirculate the combustion gas, namely CO2, to the gasification reactor as a function of the gasification agent (CO2 loop). In this study, oxygen (O2) was used as an agent gas to reduce the appearance of NOx emissions when using air and to increase the production of CO syngas. The gas composition of the agent was varied from no oxygen (I), 25% oxygen (II), 50% oxygen (III) and 75% oxygen (IV). The city waste RDF used has a composition of 94% organic and 6% inorganic with a size of 1-5mm. The performance results were obtained in variation III with the highest solid to gas conversion (FCR) value of 0.685 kg/hour with a syngas composition value of CO=4.25%; CH4=1.73% and H2=16.43% and a gasification efficiency value of 48.99%. [ABSTRACT FROM AUTHOR]

The special injection molding process GITBlow combines the characteristic features of injection molding and blow molding and enables the production of complex hollow body structures with low wall thickness and connected functional surfaces in one process. In the first step, a preform is created using the described gas injection technology. In the second step, this preform is further formed by a second pressurization similar to blow molding after the mold cavity has been enlarged. This results in a biaxial stretching of the preform material without further melt displacement. The advantage of the GITBlow compared to the underlying single processes GAIM and blow molding as well as other special processes is the following aspects: Independent of component geometry, material and process control, the gas injection technology has a gas limit pressure from which a maximum cavity / component cross section ratio is achieved. As a result of the second inflation process, this value can be significantly increased with the GITBlow process. Only blow molding allows similar or even lower wall thicknesses, but here the geometrical design freedom with regard to the connected functional elements and surfaces is severely restricted due to the process. The results obtained so far at the University of Paderborn have shown that, when simulating the GITBlow process, a division into the three characteristic process steps of the process is target-oriented. This means that three successive simulation steps are carried out, which are oriented to the process sequence. These are in detail: 1) Preform production by means of gas injection molding; 2) Temperature compensation by heat transport; 3) Inflation by means of a second gas injection In the first years of the project, the focus was on the simulation of the behavior of amorphous materials. The current goal is to investigate the blowing behavior of semi-crystalline materials in the GITBlow process. For this purpose, strain tests were carried out at typical GITBlow strain rates, the results of which are now to be integrated into the description of the process and shall be described in this thesis. [ABSTRACT FROM AUTHOR]

Detection of the target gas using the sensor can be carried out in a static headspace where gas is not flowing but is injected or in a headspace where gas is flowing. The headspace with flowing gas has the advantage of repeatedly doing gas injection and flushing processes. This paper describes the dynamic headspace design with gas flow. The chamber headspace design uses hollow aluminum with an aperture of 3.8 x 3.8 cm. At one end of the headspace, the DC fan is installed, and the other is connected to the controlling valve to allow the gas injection and air flushing. The target gas is injected into the headspace at an adjustable rate. The gas is sucked in and discharged using a DC fan. The gas flow rate is controlled via the DC fans Pulse Width Modulation (PWM) setting. Using the PWM setting, the gas flow rate is obtained in the range of 2.81 x 10−6 m3/s – 12.06 x 10−6 m3/s with PWM duty cycle of 20%-100%. Airflow velocity control is carried out using a microcontroller STM32F401. The flow rate was calibrated to a mass flow meter sensor. [ABSTRACT FROM AUTHOR]

Well CAT-07H is a producing oil well located in Cath Offshore Field. This well hasbeen producing using gas lift method which its injection gas is supplied by COM-182 compressor. In June 2019, the production of this well was interrupted by the fault of COM-182 which initially supplied 1100-1300 psi injection pressure at CAT-07H casing to only 800-1000 psi after being repaired. Due this change of injection parameter, CAT-07H was no longer able to be produced due to insufficient injection pressure. In the other hand, the well having relatively high water cut (75%) and depleted reservoir pressure made this well can no longer flowing naturally. The most possible solution for this problem is to optimize gas lift injection depth to match the new supplied gas pressure. In this paper CAT-07H is the sample well candidate to be evaluated for GLPO installation. CAT-07H is initially a gas lifted well which receive gas from COM-182 compressor. Due to decrease in performance of COM-182 compressor, gas parameter received on CAT-07H from COM 182 is no longer suitable with existing gas lift installation. Based on evaluation, gas pressure generated from this compressor decreases from 1100-1300 psi range to 800-1000 psi range. Based on this data, gas lift optimization is required to adjust gas lift on CAT-07H to meet the new pressure range. 800 psi is used as design parameter with maximum injection gas rate of 1 MMSCFD. Based on the evaluation in this thesis, it is found that gas lift can be optimized using GLPO method by changing the injection point to 2900 ft with punch port diameter if 0.15 inch which can be acieved using 1606 L puncher. After the optimization using GLPO on CAT-07H, production rate can be optimized to 2532 BFPD with net production of 633 BOPD. [ABSTRACT FROM AUTHOR]

Miscible CO2 injection is one of the enhanced oil recovery (EOR) methods by expanding the volume of oil, reducing viscosity and density, reducing interfacial tension, and extracting oil into the CO2 phase which can reduce the mobility ratio of the oil. The miscible CO2 injection method chosen is the Water Alternating Gas (WAG) method. The WAG method is the latest technology to increase sweeping efficiency during injection, minimize the amount of CO2 that must be used, reduce the mobility ratio of oil and slow down the breakthrough that generally occurs in the continuous CO2 injection method. The purpose of this study was to determine the effect of cycle time and the optimal WAG ratio on the CO2 miscible WAG injection method to obtain the highest recovery factor value in field X. Cycle time and WAG ratio are important parameters in WAG CO2 injection because cycle time is the transition time between water injection and CO2 gas injection and WAG Ratio is the ratio of the amount of water injection rate and CO2 to be injected into the reservoir. If too much water is injected, the microscopic efficiency will decrease, while if too much CO2 gas is injected, it will cause a low sweep efficiency. Research methodology with three-dimensional simulation software CMG compositional. The results obtained from the CO2 miscible WAG injection method are the most optimal slug size using 2 PV with an inverted five spot well pattern, in a cycle time of 90 days (3 months), and the optimal WAG ratio using a 1:3 ratio (injection water rate 20,036). [ABSTRACT FROM AUTHOR]

The research work presents the flow characteristics of the steady flow field of a rocket engine with a nozzle, the objective of the work is to consider one of the rocket engines, simulate and present the variation of Mach, Density, Temperature, Thrust deflection, change in momentum due to the thrust vectoring. A numerical analysis was carried out to characterize the nozzle flow field of secondary injection thrust vector control (SITVC), and a simulation results was set out to analyze the impact of switching the injection position on the SITVC nozzle fluid flow structure and SITVC performance. Parameters. Due to the complexity of the rocket flow investigation, most of the research works are performed using the computational tool. And due to the advent of Computational Fluid Dynamics, the studies involving the fluid flow problem for complex systems has been tremendously helpful. Therefore, the research work has solved numerically the compressible 2-D steady Reynolds Average Navier Stokes equation. [ABSTRACT FROM AUTHOR]

Porous ceramics offer excellent mechanical, abrasion, chemical, and thermal characteristics. In addition, these porous network ceramic structures have a less density, mass, and thermal conductivity. In this work an attempt has been made to develop a porous ceramic material based on pure aluminium added with fly ash based cenosphere added with suitable binder bentonite. Bubble type melt gas injection method is adopted for production of porous ceramic foams. Aluminium powder percentages are varied for 60, 65, 70 and 75 wt.% and the porous structure obtained is assessed using macrostructure evaluation. Also, the percentage porosity of the fabricated ceramic foam is evaluated as per ASTM guidelines. It is found that with higher aluminium percentage the percentage porosity obtained higher with a dendritic like structure. [ABSTRACT FROM AUTHOR]

The influence of foreign gas injection on the boundary layer stability of the Mach 6 nozzle of the Transit-M wind tunnel is investigated within the framework of the linear stability theory. The N-factors of the Görtler vortices and the first and second Mack modes are obtained. For a given nozzle, the most unstable disturbances are Görtler vortices. It is shown that the light gas injection leads to a significant slowdown in the growth of Görtler vortices, and the higher the mass flow rate, the stronger this effect. However, an increase in the mass flow rate of a light gas leads to an acceleration of the second mode growth in the boundary layer of M = 6 nozzle; the second mode can lead to a transition earlier than the Görtler vortices at some parameters of the injections. Heavy gas injection accelerates the growth of Görtler vortices and second mode disturbances. The growth of the first Mack mode is slower during the injection of both light and heavy gases. [ABSTRACT FROM AUTHOR]

This work is devoted to the study of the influence of light gas injection on the stability of the boundary layer on the plate at Mach number M = 5.4. The boundary layer stability is calculated within the framework of the linear stability theory. Boundary layer equations in self-similar coordinates and the Fluent program from the Ansys package are used to calculate laminar boundary layers. Gas injection is simulated from the plate surface. It is shown that the injection of light gas leads to the stabilization of second mode disturbances. First mode disturbances are destabilized in the injection region and stabilized downstream of the injection region. [ABSTRACT FROM AUTHOR]

Due to economic and ecological trends, materials used in the automotive industry are expected to be lightweight. One of the most important advantages of lightweight materials is a reduction of raw material consumption, which results in lower production costs. In the automotive and aviation industry, one of the most important features of lightweight material is its density. Obtaining material with lower density allows to reduce a total weight of a vehicle, which causes improved performance and lower fuel consumption. One of the key solutions used to produce lightweight parts in the automotive industry is microcellular injection molding (MIM), which allows obtaining a part characterized with microcellular structure, consisting of plastic and gas pores inside of a part. The most important challenge in creating lightweight materials is to achieve comparable mechanical properties to the state before density reduction. This kind of result is possible to achieve by the control of porous material's structure, primarily gas cells size, amount and distribution. This work presents the influence of gas injection parameters on a part's structure, examined with use of 2 injection simulating tools and in actual experiment, where the structure was tested in use of computed microtomography. The second aim of the work was to compare results obtained in 3 different ways, which were: Moldex3D simulation, Cadmould simulation and an actual experiment. [ABSTRACT FROM AUTHOR]

To increase the active volume of injected gas, there were analyzed current state, as well as technological and thermodynamic parameters of all wells and field equipment at the Karadag Underground Gas Storage facility. To determine the total volume of injected gas, a preliminary calculation was carried out for each of the Underground Gas Storage wells. Based on the results of field research carried out at the Karadag Underground Gas Storage facility, a number of scientific and technical measures have been developed to improve the efficiency of the active volume of injected gas and there have been presented technological result and economic efficiency of their implementation. The optimal thermodynamic and technological mode of well operation was selected during the period of gas injection and withdrawal at the Karadag Underground Gas Storage facility. [ABSTRACT FROM AUTHOR]

Waxy crude oil deposition in production pipelines often causes flow assurance issues in production operation. The issue further deteriorates during restarting of the waxy crude oil pipeline after an emergency shut down or planned maintenance. This is due to the obstruction caused by the solid wax in the pipeline, which requires additional pressure to disintegrate the solid wax before achieving a steady flow. The conventional equation used to measure the minimum pressure required for pipeline restart is overestimated, since thermal shrinkage, gas voids formation, and compressibility are neglected. The present study describes the effect of water bath temperature on the cooling time of the waxy crude oil and the effect of gas injection duration on the restart pressure of the waxy crude oil pipeline. The experiment was carried out using a waxy crude oil flow loop rig. It was observed that as the water bath temperature decreases, the cooling time increases, and the cooling rate decreases. When different gas injection durations were injected, a longer duration yields to lower pipeline restart pressure. Longer gas injection duration implies more volume of gas; hence compressibility is increased, which provides more space for the movement of the gelled waxy crude oil and its disintegration within the pipeline during the restart process. Hence, the restart pressure of the pipeline can be greatly reduced. At water bath temperature of 20°C, the highest restart pressure reduction, 40.48% is achieved, whereas at water bath temperature of 32°C, the highest reduction in the restart pressure attained is 33.52%. [ABSTRACT FROM AUTHOR]

Underbalanced drilling operation has been discussed which is classify as unconventional drilling method by making the bottom hole pressure lower than the formation pressure. To accomplish underbalanced, with lightweight drilling fluids, gas injection down the drill pipe, and gas injection through a string. It categorized in relation to the density of the fluids into five main fluid types based mainly on equivalent circulating density (gas, mist, foam, gasified liquid and liquid). Fluid type is detect by the boundary conditions of the drilling system. The economic feasibility and the comparison to the conventional drilling was covered with case studies for x well used to show beneficial effectiveness circumstances to do underbalanced drilling. The operation has been simulated in Geological formations of Egypt which help to predict whether it is possible to achieve a stable underbalanced condition by showing changes of bottom hole pressure with specific data such as design for drill string, reservoir data, mud program and well trajectory. The study is helpful to rise recovery of hydrocarbon, to reduce problems related with aggressive formation destruction and decreased cost when related with the cost of conventional drilling for the same formation. Further aids of this method help in the decrease in drilling time, larger penetration rates, increased bit life, a fast-productive reservoir areas indication, avoid loss of circulation and differential pressure sticking. One of the most significant phases of the underbalanced drilling operation is the planning phase. The applicant reservoir must assess for its appropriateness for underbalanced drilling before undertaking an Underbalanced Drilling project. It used when the formation has a flow that could be ranges under control while drilling. So, it can be used in Southern Iraq if there is much more understanding of the formations with instructions. [ABSTRACT FROM AUTHOR]

Within the oil and gas industry there are a number of key factors which are important in carrying out a review of any reservoir which include ensuring that running expenses and down time are kept to a minimum, the process of ensuring maximum yield from a well, the development of the oil field and starting from the reservoir and finishing at the well-bore assuring the consistency of the flow over the complete production system so the production predictions for the complete operation are the final necessary piece of information. For the purposes of this research exercise a specific field was selected which was not opened fully until 2007 but was drilled in the 2000s and the objective is to identify how the gas lift process might be used to improve the production capacity of the initial wells within the field. In other words, the overall capacity of the field in terms of production capability into the future under a variety of different operation procedures is the main focus of this research exercise so that a proper evaluation can be carried out. In order to do this, it was necessary to gauge the best production rate within the design parameters and to develop the optimum gas lift using the PROSPER software program and the best parameters to achieve this analysis were the comparisons between the estimated and the actual observed pressures. Using these comparisons, it was obvious that the Beggs-Brill and Petroleum Expert2 methodology was the best and it was used in the gas lift design and from this the following parameters were optimised; the most efficient rates for gas injection, oil production, amount and depth of valves and the necessary pressure for opening and closing valves. Furthermore, the detail in terms of ratios of gas to oil and how water-cut affects this were analysed as well as reservoir pressure the range of gas lift techniques. It has been observed from the simulation that the gas lift method is more economically beneficial as long as the well continues to produce when the reservoir pressure 5300 psi and water cut 60% if the gas lift process has been applied. The results of gas lift design shown that the maximum oil production rate is (1260) STB/Day with optimum gas injection rate of (3) MM Scf/Day. [ABSTRACT FROM AUTHOR]

Gas injection is an efficient oil recovery technique if it is properly design, executed and surveyed. The injection of gas into a reservoir can be designed for pressure maintenance or gas flooding for oil displacement. This article presents the evaluation of the Gas Injection Project for Pressure Maintenance in R2U YS-32 reservoir of Central Yopales Oil Field through a reservoir characterization study that consisted of four phases: Data Compilation and Validation, Reservoir Static Model, Reservoir Dynamic Model and Gas Injection Performance Evaluation. The first phase was directed to compilate and validates the data available, which allowed detecting the additional information needs and establishing a reliable database for the following phases of the study. The Static Model consisted in geologically characterizing the reservoir using a conventional methodology. This allowed validating and/or reinterpreting the main stratigraphic and structural characteristics of the R2U YS-32 reservoir, thus determining the communication between the R2U YS-32 and R2 YS-68 reservoirs. Now they represent a single reservoir called R2U YS-32. Through static modeling, original oil in place (OOIP) of 33.35 MMbbl was volumetrically estimated. The Dynamic Model comprised the monitoring of production, injection, and pressure of the reservoir. This phase was developed, in large part, parallel to the Static Model phase. Through dynamic modeling, it was determined that the reservoir was initially saturated at a pressure of 1490 psi with a bubble pressure of 1617 psi and a gas cap size of m = 0.1255. It was also determined that the main mechanisms of production during the natural depletion period were the expansion of fluids and water intrusion, while gasinjection is the main mechanism during the secondary recovery. In addition, in this phase the volumetric OOIP was validated satisfactorily by material balance, being estimated at 33.33 MMbbl. Results showed that the gas injection did not achieved the expected results, basically because it did not manage to maintain reservoir pressure, minimize the advance of the aquifer, nor evenly sweep the oil towards the producing wells. This was mainly due to that during the first years of the gas injection, a large part of this was produced through the YS-68 well, which is connected to the reservoir's gas cap through a non-sealing fault. Additionally, the required gas volumes were not injected during the rest of the injection period. Since the reservoir has not produced since 2002, it is suggested to analyze different alternatives scenarios to reactivate the reservoir oil production including techniques like cyclic water injection or dump flooding that had been studied and planed in reservoirs/fields close to the Yopales field. [ABSTRACT FROM AUTHOR]

On the basis of the presented mathematical model, the problem of the formation of gas hydrate during the injection of gas (methane) into a porous layer of finite length, initially saturated with methane and ice, is considered. The cases when hydrate formation occurs both on the frontal surface and in the extended region are investigated. It is established that a part of the gas hydrate formed in the extended region can dissociate in the future, and the extended region of hydrate formation can degenerate into a frontal surface. [ABSTRACT FROM AUTHOR]

On the basis of the presented mathematical model, the problem of the formation of a gas hydrate during the injection of gas (methane) into a porous edge of the bed length, initially saturated with methane and ice, is considered. Cases where hydration formation occurs both on the frontal surface and in an extended area have been investigated. It has been established that a part of the gas hydrate formed in an extended region can further dissociate, and the extended hydrate creationregion can degenerate the military surface. [ABSTRACT FROM AUTHOR]

At the time of primary production, a large amount of oil reserves are left in the reservoir. The purpose of this research is to determine the results obtained from the CO2 injection and water injection methods.Therefore, CO2 injection is one of the Enhanced Oil Recovery (EOR) methods used for the remaining oil reserves in the reservoir. Water injection is used to maintain the energy reservoir to ensure that oil is pushed from the reservoir into the production well. In this study CO2 and Water Flooding were analyzed using a literature review from previous studies and the results of the simulation of these 2 methods.. The method used in this research is the observation of the mechanism and the results obtained with the two methods. The results showed that the oil production at the beginning of gas injection increased significantly and was almost the same as water injection of 5,000bbl/day. The decline in oil production using CO2 gas injection was faster compared to water, due to its low small viscosity and gas density. In addition, the injection of CO2 gas led to the recovery of oil from a larger one with a difference in acquisition of 1-2%, which would be greater when the injection volume is increased. It was concluded that water flooding may be injected at a depth of less than 1000ft with an average permeability of 10mD and oil saturation of less than 5%. Meanwhile, CO2 injection may be injected at a depth of over 2500ft. Therefore, both types of injection were suitable for sandstone or carbonate rocks. From the results of this study it can be concluded that the difference between the two methods is the type of miscibility where CO2 injection is miscible, while water injection is not mixed. These two things have two different mechanisms. [ABSTRACT FROM AUTHOR]

The theoretical and experimental investigation of the effect of the heavy gas (sulfur hexafluoride) blowing into the boundary layer on the hydrodynamic stability to controlled perturbations of the supersonic flat-plate boundary layer at Mach number 2 have been carried out. Artificial perturbations have been entered in the model's boundary layer by using a harmonic point glow discharge perturbation source. It is obtained that heavy gas blowing stabilizes the supersonic boundary layer. In experiments at the excitation frequency f = 14 kHz, unit Reynolds number Re1 = 3×106 m−1 and streamwise coordinate x = 90 mm, it was obtained that for gas injection rate Q = 0.12 g/cm2 there is a stabilization of perturbations for all spanwise wave numbers, i.e. the complete stabilization of perturbations – for all wave numbers, the spatial disturbance amplification rates are less than zero. [ABSTRACT FROM AUTHOR]

Surface modification of carbon-based nanoparticles has become essential and is challenging for bio-applications. The submerged arc discharge method is a promising technique because liquid can be used as the medium for both synthesis and surface modification at once. Submerged arc discharge using gas injection is rarely applied; therefore, the surface characteristics of the nanoparticle product have not yet been reported in detail. In this study, we investigated those surface characteristics using Fourier transform infrared (FTIR) spectroscopy to analyse the functional groups attached to the carbon nanoparticle produced by submerged arc discharge in ethylenediamine medium under different gas injections of N2 and Ar. The FTIR analysis indicated successful amine-surface modification of nanoparticles produced in arc discharge in the ethanol-ethylenediamine medium. This conclusion was reached from the observation of several absorption peaks at wavenumbers of 1020 cm-1, 870 cm−1, and 700 cm−1 as C-N vibrations, NH2 wagging and twisting, and NH2 bending, respectively. The effect of variations of gas injections influences the characteristics of FTIR spectra. Altogether, the representative peaks of amine groups have different performance signals due to variations of gas injections. [ABSTRACT FROM AUTHOR]

Injection foam molding provides the industry with advantages from production through to the life cycle of plastic components. Despite numerous applications, many questions regarding the fundamentals of this technology are fraught with uncertainty. One aspect of supreme importance is the relationship between the gas content during processing and its influence on the process and part performance. To refine the foaming technology and to comply with modern market requirements, it is crucial to understand this dependence, as proper process design and tailoring of mechanical properties require this knowledge. This work represents a thorough investigation of the influence of CO2 content on both the process and the produced components. Using talc filled polypropylene in a MuCell® process, initially the dynamic solubility limit, i.e. the ultimate amount of gas dispersible in the polymer melt during an injection molding process, was determined via a bulk modulus methodology. During this procedure, foamed plates were molded at different CO2 contents. Processing parameters, morphology and bending behavior of the produced plates were monitored and measured. The results show interesting mechanical behavior, especially close to the determined solubility limit. Based on these outcomes our experiments clearly argue for larger gas contents in physical foaming, which also benefit injection pressure/work or torque during processing. In contrast to these findings, trials with a chemical blowing agent (also yielding CO2) were carried out with the same material. The TGA of the blowing agent yielded an astonishing difference regarding gas concentration in the melt of one order of magnitude compared to physical foaming. In spite of the vanishingly small amounts of gas in chemical foaming, a fine morphology developed. This study provides novel insights into the complexity of injection foam molding, critically assesses gas contents during processing but also poses new questions.. [ABSTRACT FROM AUTHOR]

Such extreme work conditions as underwater offshore production on the Arctic shelf fundamentally new types of compressor units is required using. The efficiency criteria for the Arctic gas producing complexes are met by the compressor based on the gas-dynamic vibration scheme, the principle of kinetic compression and volumetric gas injection during the vibrational piston-nozzle motion in the sound frequency range. The complete absence of mechanical friction of the structural elements the advantage of the compressor. This paper considers a multi-stage scheme of the compressor with electromagnetic actuator for hydrocarbon production and the recent health estimated analysis on the calculation kinetic magnetoelectric compressor compression volumetric discharge as an analogue wave compressor basis. [ABSTRACT FROM AUTHOR]

The subject of research was an opposed reciprocating compressor (RC) providing gas injection into the underground gas storage. Issues concerning implementation of compressor start-up conditions to recirculating line have been considered. As a tool, the compressor-network analysis method is used, which consists in determining the system operating points through matching characteristics of the reciprocating compressor and the network, for which in this case the recirculating line with the control valve is considered. Recommendations have been received to select a control valve type for the reciprocating compressor operating in both single-stage and two-stage modes. [ABSTRACT FROM AUTHOR]

The foam injection molding process provides a multitude of advantages both during production and throughout the life cycle of foamed components. Yet still there are many uncertainties concerning the conditions inside the cylinder during gas injection. For a better understanding of these processes, the solubility of gases in polymers is crucial. In current literature, almost exclusively static solubility is investigated. It is questionable whether results from static solubility measurements are relevant for highly dynamic processes like injection molding. Additionally, it is unknown whether the limits detected in static measurements also count for dynamic systems. In this work, a novel measurement method based on the bulk modulus of gas containing polymer melts, which provides in-line determination of dynamic solubility limits, was applied. Using a talc filled polypropylene in a MuCell®-process the question was whether the solvable amount of gas can be influenced and increased by a larger gas injection time to dosing time ratio (Rt=ti/td). Starting at a gas concentration that was initially beyond the solubility limit the ratio Rt was increased stepwise, while process pressure and gas content were kept constant. The bulk modulus method in combination with transmissive ultrasonic measurements proves that the dynamic solubility can be increased above 1.6 wt% nitrogen at 140 bar. In addition, compression work and injection work were monitored and compared to the respective states of solution. These findings show that the influence of material on solubility limits might only be relevant at long dosing and gas injection times as an equilibrium cannot develop in short times typical for injection molding. This approach is useful when large amounts of gas should be dissolved in the melt in order to achieve high density reductions. It opens new perspectives for injection foam molding. [ABSTRACT FROM AUTHOR]

In this work the quality of the slim-tube packing was demonstrated, the inner diameter and porosity was determined by using X-ray computed tomography. The literature analysis of slim tube packing over was carried out. It is noted that in all cases of slim tube does not accept the most theoretically possible dense rhombic packaging. Moreover, the presence of interstices due to loose contact of the grains to each other illustrates the technological limitations when filling out. To confirm the absence of signs of defective packing, it is recommended to check the quality of the slim-tube. [ABSTRACT FROM AUTHOR]

A critical issue concerning geomechanical safety for UGS (underground gas storage) in compartmentalized reservoirs is fault reactivation. Indeed, the displacement (land subsidence, land upheaval) and the stress fields caused by the seasonal injection and production of CH4 into and from deep reservoirs is peculiar. The need of improving our understanding of compartmentalized reservoir behavior and to define safe bounds for the pressure fluctuation in order to prevent undesired land movements and induced seismicity is becoming even more important. This also in view of the expected energy transition when large amount of green energy will potentially be stored and recovered through UGS of compressed air or hydrogen. In this framework, an in-depth modelling investigation has been carried out for the typical UGS geological setting and operations in The Netherlands. The specific goals of the study are the following: (i) explaining the possible mechanisms responsible for seismic events unexpectedly recorded during UGS phases; (ii) understanding which are the critical factors (e.g. the geological configuration, the geomechanical properties, and the reservoir operations) that increase the probability of fault reactivation during the various UGS stages; and (iii) advancing possible guidelines for safe UGS operations. This contribution summarizes the main outcomes obtained by the modelling simulations: the combinations of factors causing fault reactivation during primary production (PP) are also more prone to generate fault failure during cushion gas injection (CG) and UGS. In fact, fault activation during PP leads to a stress redistribution and a new (deformed) "equilibrated" configuration that is newly loaded, in the opposite direction, when the pressure variation changes the sign because of CG and/or UGS. Finally, the various combinations have been ranked to highlight the conditions where the fault system is most likely reactivated during CG and UGS operations: the initial stress regime of the system, the geomechanical properties of the fault, and dislocation of the reservoir compartments are the major influencing drivers to fault instability. [ABSTRACT FROM AUTHOR]

Dual fuel (natural gas (NG)-diesel oil (DO)) is one of the interesting strategies that can be applied to diesel engines related to emission reduction. On the other hand its application causes a decrease in diesel engine performance. So it is necessary to look for system settings that can produce the best performance. One possible setting to analyze is the NG injection pulse width. In this study, a variation of NG injection pulse width was carried out to determine the effect on the engine performance at low to high loads. From the experimental results, it can be seen that the variation of gas injection pulse width does not significantly affect torque, power, and BMEP. There is an increase by reducing injection pulse width up to 9 ms in medium and high loads but the changes are small. Variation of injection pulse width 11 ms has the lowest SFOC and the highest thermal efficiency at medium to high loads. While the biggest substitution is obtained by injection pulse width 12 ms but at 75% load, the substitution is lower than 11 ms. [ABSTRACT FROM AUTHOR]

The progress of the improvement of dual-fuel diesel engines with diesel and natural gas fuel is quite significant. One of them implemented the split injection strategy or can also be referred to as multiple injections. This study analyzed the effects of natural gas split injection on the combustion and emission of modified dual-fuel diesel engines. The study was carried out numerically at 2000 rpm at low to high loads using proportional injection between the first injection (160°BTDC) and the second injection (100°BTDC). Moreover, natural gas substitution is maintained at 50% of the total fuel energy used. The simulation model is calibrated with the appropriate engine size. In addition, the model is validated with the results of experiments on engines with the same parameters. Results from natural gas split injection were compared with single-injection natural gas on different injection timings (160°BTDC and 100°BTDC). The results show that natural gas split injection has a significant effect on different loads. The split injection causes an increase in peak cylinder pressure and heat release rate thereby increasing torque at all loads compared to the single injection. Fuel consumption, CO, and HC in split injection mode are smaller compared to the single injection at 160°BTDC injection timing and greater than 100°BTDC at low loads up to 75% load. However, at high load is greater than all single injection. NOx split injection emissions at high load actually decrease compared to the single injection. [ABSTRACT FROM AUTHOR]

The use of Natural Gas (NG) in internal combustion engines has been increased in this decade. The objective of this paper is to investigate the NG injection timing on the dual-fuel engine. In this paper experimental based on dual fuel engine strategy (DFE strategy) was tested with several variations of gas injection based on CA at the modified direct-injection engine into a DFE strategy. In the data test, the variation is CA 260, 244, 230, 214 bTDC. This research is for observed how it affects the engine performance. The indication of the effect of NG injection based on the CA variation is the non-homogenization of the NG-air mixture in the intake manifold, and the delay in mixing NG-air to go into the combustion chamber. From several data tests that have been done, there is an increase in engine power, thermal efficiency and a decrease in SFOC fuel consumption. The optimum combination of the DFE strategy has a fluctuating value when taken from test experimental data. The trend is seen, that CA 230 bTDC is the optimum value to be operated in the DFE strategy. Because there is an increase in Torque, Efficiency thermal, and a decrease in SFOC of fuel consumption. [ABSTRACT FROM AUTHOR]

Development of marine engine technology is driven increasingly by strict emissions regulations. Dual fuel technology which uses natural gas as supporting fuel is a smart solution due to it is cleaner, cheaper and can reduces dependency on fossil fuel oil. However the phenomenon of methane slip is the biggest challenges on applications of diesel – natural gas dual fuel engine. A large amount of fuel with poor oxygen especially when engine on low load condition make some parts of methane were unburned, these uncompleted combustion raises methane slip. Meanwhile crevice or dead volume in the cylinder make gas trapped and come out as exhaust gas without participating on combustion. It is evident that being the same greenhouse gases the effect of methane slip is more dangerous than CO2 causing global warming and climate change. This research was carried out experimentally to find out how the natural gas injection time affected on the combustion performance and methane slip. On this study, three variation pulse width as injection timing of natural gas 260° BTDC, 230° BTDC and 214° BTDC were investigated to single cylinder diesel engine on constant speed 2000 rpm. The pressure of gas injection was taken fixed 3 bar, while the pilot injection timing was constant at 18 BTDC. From 30 cycles analyzed at each injection time, a significant relationship was found between optimizing the gas injection time and the gas duration to the methane slip value. Backing the injection time towards the closing of the intake valve with the right injection duration can reduce the value of methane slip. Although the 260° BTDC injection time in this research is optimal compared to the others due to the CNG wasted due to the duration of the injection that passes through the intake valve. [ABSTRACT FROM AUTHOR]

This paper concerns the description of the one-dimensional steady-state flow pattern arising from the injection of gas at supersonic velocity into a duct of uniform or diverging cross-sectional area when back pressure is applied. The considered problem is described by a boundary value problem for a singularly perturbed second order ordinary differential equation with a small parameter. But the solution of such problems is difficult, especially for small values of the parameter. Until today, there is a need to create new effective methods for solving singularly perturbed boundary value problems. The aim of the work is to find a solution to one typical aerodynamics problem. Obtained solutions will allow testing methods of numerical and asymptotic solving of this type boundary value problems. The exact solution has obtained for the constitutive equation in the case of uniform cross-sectional area. The paper found a considered problem general solution, which is divided into three independent branches. On this basis, systems of transcendental equations for finding the exact solution of the considered boundary value problem are given. The possibility of the obtained equations systems solvability and the uniqueness of the boundary value problem solution are discussed. The results obtained are in good agreement with the results of the asymptotic analysis carried out in the works of Chang, Howes, and Crocco. The form of the analytic relations confirms the possible presence of boundary and interior layers on the integral curves of the considered boundary value problem. [ABSTRACT FROM AUTHOR]

The special injection molding process GITBlow was developed by the Kunststofftechnik Paderborn and combines the processes of gas assisted injection molding (“GIT”) and blow molding (“Blow”). The parts feature large, thin-walled hollow spaces and additional functional elements. This is realized by using two consecutive gas injections and a mold with two cavities of different sizes. The first gas injection creates a hollow space within the part. In a second larger cavity the hollow space is inflated further by a second gas injection. The aim of the current research project is to manufacture hybrid structures consisting of GITBlow structures and continuous fiber-reinforced thermoplastic sheets. The new approach is to join the parts with the molten sheet material during the final phase of inflation in order to strengthen the parts locally. The parts produced with this process are characterized by their low weight, large volume and high compressive strength. To achieve the highest possible bond strength between the two components, it is necessary to maximize the temperature of the GITBlow part within the joining area. In a case study with Polycarbonate (Covesto Makolon OD 2015) and Styrene-Butadiene copolymer (Styrolution Styrolux 656C) the influence of the melt temperature and various process times on these factors can be shown. For PC a maximum temperature in the joining area of 165°C can be achieved while still maintaining optimal part quality (SBC: 120°C). Further investigations show that heat transfer within the part is of major importance for the final temperature distribution. With this knowledge an optimization of the process concerning the production of hybrid structures can be achieved. [ABSTRACT FROM AUTHOR]