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This study focuses on the effects of continuous volumetric discharge of sinusoidal plasma actuator at 20 kHz coupled directly with methane-air premixed flame in the near field of the injector exit. A plasma actuator composed of a needle-type electrode placed at the center of the nozzle, connected with high-voltage, while the nozzle was acted as a grounded electrode with different input electrical power values was designed to enhance lean blowout performance in a swirl model combustor. The ionic wind induced by the electrical body force given by the flow ionization leads to velocity disturbance and subsequently affects the flame. To investigate the possible mechanism of the combustion control by the plasma through the aerodynamic effect high speed flow visualization was analyzed under quiescent conditions. Flow visualizations showed that the plasma discharge affects the flow dynamics near the burner exit. It was observed that by increasing the electrical power used for the actuation a recirculation zone is formed in the non-reacting flow field. Furthermore, comparative experiments between conventional and plasma-assisted combustion were carried out to analyze the combustion enhancement in terms of lean blowout performance. The effect of the input electric power of the plasma actuator was studied, and it was seen that at coupled plasma powers corresponding to less than 1% of the thermal output power, there is a significant improvement in the blow-out limit.

This paper investigates the influence of using thermopressor devices in the heat using ejector refrigeration machine cycles. The thermopressor is a multifunctional apparatus in which refrigerant vapor is cooled, and a simultaneous pressure is increased. A calculation method was used to determine the thermodynamic and energy efficiency of a thermopressor as part of an ejector refrigeration machine. It is proposed to use the apparatus for cooling the vapor in front of the condenser. The calculation considered the pressure loss in the nozzle (confuser), the working chamber, the diffuser, and the frontal resistance of the injected liquid droplets. The thermopressor application in the ejector refrigeration machine cycle allows increasing the ejection coefficient and the ejector refrigeration machine thermal coefficient due to increasing the pressure. The expected increase in the thermal coefficient is 1.5–2.0%. The results obtained are an important contribution to the development of thermopressor technologies and can be used to design jet devices.

This chapter presents a detailed theoretical study, numerical modelling and some applications for solar heating and cooling systems focused on active and combisystems. Important information’s on simulating solar heating systems are discussed and the TRNSYS program is also briefly described. Additionally, a detailed review of different solar thermal-driven refrigeration and cooling systems including sorption technology (open systems or closed systems) and thermo-mechanical technology (ejector system) is also provided. The study refers to a comparison of various solar thermal cooling systems, and to some suggestions for the use of these systems. A comprehensive survey of solar thermo-electric (TE) cooling systems is also provided. Finally, the possibility of solar TE cooling technologies application in “nearly-zero” energy buildings is briefly discussed and some future research directions are included.

The primary objective of a liquid fuel injection system is to provide the combustion chamber with the proper amount of fuel and with a spatial pattern that will result in efficient combustion over the entire flight path of the ramjet. In [1], empirical methods for designing fuel injectors were defined. In this work, the approach of Wu [2] to calculate the breakup time of the jet, the correlation of Lefevbre [3] for the average diameter of the droplets of fuel, the study of Turns [4] to calculate the time of vaporization of the droplet and the data processed by Kundu, Colket and Fuller [5, 6, 7] for the delay have been selected to provide guidelines to injector design.

A conventional ramjet combustion chamber is simply a hollow cylinder. Combustion chambers may be divided into single stage and two stages according to the organization of their combustion processes. A stabilized combustion chamber includes the following elements: (1) an installation for the introduction and atomization of the fuel; (2) ignition units; (3) turbulence rings; (4) flameholders; (5) mixers. Spark ignition, ignition by incandescent wire, and pyrotechnic ignition are possible means of igniting the fuel mixture. Spray, swirl and pneumatic injectors are used to feed the fuel into the combustion chamber. The design of individual elements depends upon the purpose and upon the dimensions of the combustion chamber.

In-cylinder fuel-air mixing quality is significant to improve economy performance, power performance, and emission performance of diesel engines. An in-cylinder mixture formation process is a complex unsteady process, which is influenced by a fuel injection system, fluid flow, and the geometry of a combustion chamber. Spray characteristics of a high pressure common rail diesel engine are investigated in this paper by using the methods of experimental and numerical simulations. The influence of different injection pressures and different back pressures on spray characteristics are studied, in a constant volume bomb by means of two high-speed cameras. Results show that the cavitation inside the injector affects the fuel-air mixing processes. It's possible to increase the chamfer at the entrance of the injection hole to suppress the cavitation phenomenon inside the injector. Increasing fuel injection pressure is conductive to the promotion of fuel diffusion and evaporation, thereby improving the uniformity of fuel-air mixture and the speed of fuel-air mixing processes. Higher back pressure can help to reduce the concentration of fuel-air mixture and improve mixture uniformity. However, it is an adverse effect on the speed of fuel-air mixing processes.

The current state-of-the-art combustion control concepts are based on cycle-to-cycle actuation and the control of cycle-integral values. A more advanced combustion control concept, the so-called combustion rate shaping, aims to control the combustion process in a highly time resolved manner. In case of the fullest extent, the crank-angle-resolved in-cylinder pressure signals are controlled. The concept relies on the actuation side on injection systems that are highly flexible as given for modern injection systems. In this chapter, two aspects of the combustion rate shaping are detailed. First, the modeling of the combustion process is investigated. A low-order model is required that is able to reproduce the combustion process in case of highly flexible injection events. A suitable approach based on data-based models is presented. Second, the digitalization of a continuous injection profile is examined. Digitalization is needed when a series-production injector is applied as they are only capable of realizing digital injection events. In both parts, optimization-based methods are depicted.

In modern Launcher Rocket Engines (LRE), the study of the behavior of the injector in combustion chamber has been complicated by the fact that lower fuel temperature and higher pressure are used to achieve larger enthalpy values. In addition to this, methane has become more and more common in aerospace application, therefore transcritical states are often reached by the mixing of fuel and oxidizer. The goal of this work is to correctly characterize the transcritical mixing of coaxial \(N_2/H_2\) injector. Real-gas thermodynamic is used for this purpose in combination with appropriate inlet turbulent boundary conditions. In particular, an effort has been made to use realistic inlet turbulent conditions and a high order scheme has been employed for the calculation of the convective fluxes.

The stability behavior of a virtual thrust chamber demonstrator with low injection pressure loss is studied numerically. The approach relies on an eigenvalue analysis of the Linearized Euler Equations. An updated form of the stability prediction procedure is outlined, addressing mean flow and flame response calculations. The acoustics of the isolated oxidizer dome are discussed as well as the complete system incorporating dome and combustion chamber. The coupling between both components is realized via a scattering matrix representing the injectors. A flame transfer function is applied to determine the damping rates. Thereby it is found that the procedure for the extraction of the flame transfer function from the CFD solution has a significant impact on the stability predictions.

High-order spatial discretizations significantly improve the accuracy of flow simulations. In this work, a multi-dimensional limiting process with low diffusion (MLP$$^\text {ld}$$) and up to fifth order accuracy is employed. The advantage of MLP is that all surrounding volumes of a specific volume may be used to obtain cell interface values. This prevents oscillations at oblique discontinuities and improves convergence. This numerical scheme is utilized to investigate three different rocket combustors, namely a seven injector methane/oxygen combustion chamber, the widely simulated PennState preburner combustor and a single injector chamber called BKC, where pressure oscillations are important.

The principal components, i.e., the combustion chamber and the nozzle, of the thrust chamber of a rocket engine are presented and discussed together with their performance parameters. Injectors, engine cycles, and igniters are discussed. Methods are given for their quantitative design. Cooling systems and combustion stabilising devices are also presented.

The dynamics of improvement of equipment and technology of dust suppression in the mining and metallurgical complex of Russia shows their insufficient efficiency of providing sanitary conditions, and most importantly the localization of explosions of dust mixtures. Further increase of efficiency of coal mining and mineral processing is significantly limited by the imperfection of technology of localization and elimination of coal dust explosions. On the basis of the theory of attached vortices the method of high-pressure hydro-vortex dust separation is developed. The mathematical model of the hydro-vortex inertial, kinematic heterocoagulation, significantly increasing the energy efficiency of dust suppression, is proposed. The graphical model of interaction in the contact zone at the moment of collision in the system “liquid-solid” is refined; the equations of the Stokes and Reynolds criteria for hydro-vortex inertial orthokinetic heterocoagulation are obtained. An equation for calculating the value of the reduction of the required energy of the total absorption of dust particles in the function of the liquid droplets circulation is obtained. The equations for the calculation of the effective contact angle and the minimum diameter of the absorbed dust particles in the function of the liquid droplets spin rate are obtained. It is shown that the hydro-vortex coagulation significantly reduces the size of the dispersed dust composition, water consumption, increasing the efficiency of dust suppression. A significant reduction in the size of the dispersed dust composition increases the efficiency of the system of localization of coal dust explosions, reduces the morbidity of silicosis. The use of patent-protected swirl injectors has confirmed the reduction of the minimum size of the absorbed dust by four times, increasing the efficiency of dust collection up to 99% while reducing the water consumption at 20%.

Almost all hydraulic systems in hydropower stations are constructed for turbine and pump operations. Except for Pelton turbines, at which only the injector nozzles are included in the hydraulic system, all other types of turbines and pumps are found within the hydraulic network and the pipeline system. This fact determines that to compute each hydraulic transient the hydraulic characteristics of the respective turbines and pumps must be taken into account. In case of emergency shutdowns of turbines or pumps, for instance, the extended characteristics of these machines with changeable rotational speed must be known. Furthermore, the moment of inertia of the entire rotor system plays an essential role in affecting the changing rate of rotor rotations.

The flexibility in managing the air-fuel mixture formation in engines equipped with Gasoline Direct Injection (GDI) has demonstrated being an effective system to pursue the growing demand of energy efficiency and reduction of pollutant emissions. This injection modality improves the spray characteristics in terms of a better atomization of the fuel, finer droplet size and better distribution in the combustion chamber to enhance the combustion efficiency. Nowadays, it is known that very high-pressure injections are adopted in GDI systems to improve the spray atomization and, subsequently, the evaporation processes in the engine combustion chamber. In this study, the investigation of the influence of the pressure on gasoline spatial spread and thermo-dynamic status was carried out for different ambient densities (from 0.2 to 11.50 kg/m3) and gas temperatures (from room to 200 °C) by a hybrid optical setup, shadowgraph and Mie scattering, to acquire in a cycle-resolved mode both the vapor and the liquid phases of the spray. The study was performed in a constant volume chamber (CVC) using a ten-hole GDI injector, 0.10 mm in diameter, with the injection pressure ranging from 40.0 to 100.0 MPa. The influences of the ambient and injection conditions on the characteristic parameters of the jets, such as tip penetration, cone-angle, and fuel spread, were extracted by a customized image-processing procedure developed in C#.

One of the ways to determine the fire resistance of building structures is to conduct tests in special fire furnace. The design, metrological instruments and control methods of the fuel supply system and injectors in these furnaces are not perfect. Conditions that created in this way ensure uneven temperature distribution over the heated surfaces of the tested structures in combustion furnaces.

A stochastic sensitivity analysis and calibration of the cavitation model parameters in the URANS simulations of a configuration representative of high-pressure injectors for automotive applications is carried out. A popular homogeneous-flow cavitation model is considered, in which the mass transfer due to cavitation is given by the Schnerr–Sauer model together with the classical Rayleigh–Plesset equation. A stochastic approach based on the generalized Polynomial Chaos (gPC) expansion is adopted, which allows continuous response surfaces of the quantities of interest in the parameter space to be obtained starting from a few deterministic simulations. The considered uncertain parameters are the so-called scaling factors. The calibration of these parameters is carried out by using the gPC response surfaces for a axisymmetric simplified geometry against the experimental value of the critical cavitation point, i.e. the condition at which the injector is choked. The procedure is carried out for two different turbulence models, viz. the k − ω SST and RSM models. The so-obtained optimal parameter set-ups are then validated for the real three-dimensional geometry. The k − ω SST optimal set-up gives very accurate predictions also in the three-dimensional case. Finally, the results obtained with this optimal set-up are compared to those given by standard values, confirming that the predictions of the different flow regimes occurring in high-pressure injectors are highly sensitive to cavitation model parameters.

Multipacting in an elliptic superconducting cavity can occur near the equator, but it is usually not very strong, and as shown in Chaps. 8 and 10, one can eliminate this multipacting by changing the cell shape in the equatorial region. It was thought that such cavities are essentially multipactor-free. However, tests of the Cornell Energy Recovery Linac (ERL) injector cavity [2] and KEK Ichiro cavity [3] showed relatively strong multipacting, which was later attributed through computer simulations to the transition regions between the cavity end cells and beam pipes. For the ERL cavity, the presence of multipacting in this region was experimentally confirmed by measuring electric current at a biased probe and correlated temperature changes at the outer wall [2]. Our analysis shows that the amplitude of the electric field along the cavity profile line has a minimum at the location of the multipactor discharge. Similarly, the possibility of multipactor existence in the transition region was found during our work on designing a multicell superconducting cavity for the future Cornell ERL main linac.

The article addressed and resolved issues of improving the energy efficiency of vacuum units: motor - liquid ring pump with an upstream ejector. The purpose of the study was to determine the relationship between the required power N and the magnitude of the residual pressure of the vacuum water-ring pump BBH-0,25 psat, the pre-actuated stationary BBH-0.25E and the pulsed BBH-0.25EP ejector. The way the system modeling asynchronous motor - liquid ring pump - ejector ballasts (BP-VVNE), which is based on a joint consideration of the electrical, hydraulic and gas dynamic subsystems. Simulation System AD-VVNE carried out on the basis of the equivalent circuit, which is not done by the authors of known works devoted to the modeling of water ring pumps with ejectors. At the same time the actual asynchronous car with electromagnetic interactions between windings is replaced with rather simple electric circuit that allows to simplify calculation of characteristics significantly.

Currently, concern in the development of the Far North and the Arctic has sharply increased. High-power air-cooled diesel engines can be widely used in such severe conditions. In this regard, the problem of determining the possible limits of forcing air-cooled diesel engines becomes relevant again. The solution of the problem was performed by calculation and experimental determination of possible limits of forcing air-cooled diesel engines according to the chosen criterion that defines the forcing limit. As a result, the acceptable levels of forcing air-cooled diesel engines supercharged at different excess air ratios, and the degree of cooling of supercharged air were determined. Based on the analysis of the calculation results, it is concluded that supercharged air-cooled diesel engines are particularly critical to the ratio of the boost pressure to the back pressure at the outlet. It is shown that with an increase in this ratio, the maximum and average temperatures of the injector firing face decrease linearly. The estimation of the possible limits of increasing the diameter of the air-cooled diesel cylinder with different levels of forcing on the average effective pressure is performed.

The design of injector nozzles providing improvement of the fuel injection and atomization processes quality in diesel engines is suggested. This is achieved by making grooves on the injector nozzle, each of which forms an expansion of the output channel of the corresponding spray hole. Experiments have been carried out for the D-245.12S diesel engine, alternately equipped with experimental and serial injector nozzles, and operated on diesel fuel, and on 80% diesel fuel and 20% rapeseed oil mixture. The possibility is demonstrated in terms of improving the exhaust gases toxic characteristics using the diesel engine equipped with the experimental injector nozzles and operated on 80% diesel fuel and 20% rapeseed oil mixture. The combination of the experimental nozzles and composite biofuel, containing 80% of diesel fuel and 20% of rapeseed oil, resulted in lower emissions of nitrogen oxides by 8.1%, of carbon monoxide—by 12.4%, and of unburned hydrocarbons—by 15.9%.

We theoretically determined the estimated model for the fuel supply system, which allows us to investigate the relationship of the maximum engine crankshaft speed with the change in the technical condition of individual elements of the fuel system. The change in the pressure and capacity of the fuel system is associated with the change in the flow characteristics of the electromagnetic injectors, filter resistance, and technical condition of the pump. In connection with various mechanisms of failures of the fuel system elements and changes in their technical condition, we considered a simulation model of the fuel system. We presented the results of studying the output characteristics of electric gasoline pumps of the vehicles’ fuel system. We considered two diagnostic methods to determine the technical condition of the pump: dynamic and static. To control the technical condition of the fuel system elements, we developed a testing method based on load and stress testing. For a pump used in a vehicle, the change in its characteristics with the change in the supply voltage typical for these conditions is of a great importance. The paper presents a study of the relationship between the technical conditions of the gasoline electric pump with its quality indicators of the fuel system operation. We determined that it is possible to monitor the technical condition of the pump by measuring the difference of the values of the crankshaft speed when the sparking and fuel supply are off. We presented experimental results by the dynamic method, which has the most informative and information capacity.

Modern diesel engines are equipped with a Common Rail injection system. The injector is probably the most complex component in this system. To facilitate Common Rail system testing or research it can be individually mounted, separate from the engine, on an experimental stand. In this way, the shape and characteristics of the fuel jet can be analyzed more easily. Viewing and analyzing the electrical signal was done in the paper through the AVL Indicom program. In the paper is analyzed the control signal of an electromagnetic injector, during injection of a quantity of fuel from 2 to 40 mg, with differed strategy injection: one, two or three injections.

Fuel combustion optimisation in compression-ignition engines with multi-stage HPCRS injection is the main direction of research in the area of the thermodynamic stability of fuels with FAME addition, also including the formation of PM. This paper presents stages of multi-aspect diagnostic inference in relation to the causes of failures of an engine’s functional systems as a result of PM deposits. The engine operating parameters were evaluated using a dedicated tester, showing the significance of diagnostic procedures during the vehicle servicing periods, which prevent the occurrence of emergency states signalled by the MIL warning lamp. The diagnostic procedure showed a gradual injector dysfunction which contributed to PM formation, necessitating an earlier service intervention. XRF spectrum analysis in relation to the determination of elements forming the PM along with IR spectroscopy showed the presence of organic FAME compounds in the PM deposit.

Two-phase nozzles can work in jet injectors of various applications, including jet heat pumps (steam-water injectors) and thermocompressors. Lack of a reliable description of the mechanism of the evaporating liquid flow limits their use as energy-efficient working bodies. The estimation of effect of the vapor content on the initial pressure and temperature will make it possible to determine the variant of initial parameters, at which the overproduction of the vapor is the greatest. The goal of this work is to investigate the effect of pressure and temperature at the nozzle inlet to outlet vapor content. We use the model of a compressible two-phase medium, the kinetic model of evaporation/condensation. The model also includes the dynamic and mechanical equilibrium of the process. The mathematical model using CFD package of Ansys CFX software considers the dynamic growth of the vapor bubble. The obtained results show the average deviation from the experimental value, particularly 2% for pressure and 10% for speed. Increasing pressure and temperature at the nozzle inlet leads to increasing the vapor mass fraction at the nozzle outlet.

Now, two approaches are known for simulating a two-phase flow of sprayed liquid in a gas by using an injector. These are a method of mutually penetrating continua and the method of turbulent jets. Taking into account the flow peculiarities revealed in the analysis of the experimental results, it turned out that none of the abovementioned approaches taken separately can be used to model the spray flow. But it is possible to use their combination.

The basis of the method for calculating the processes of heat and/or mass transfer in a two-phase gas-droplet system consists of equations describing the hydrodynamics of such a system, taking into account the interfacial interaction. Knowledge and understanding of the mechanism of interaction of phases in a two-phase flow, which is created by spraying a liquid in a gas, is definitely not sufficient (as will be shown below). This is one of the main reasons for the abovementioned problem (see Chap. 1).

In this paper, a bench study of the pump-ejector system for simultaneous water and gas injection (SWAG) was conducted. For these purposes, a pump-ejector system stand was used. A differential pressure gauge was used to determine the gas flow at the ejector intake. According to the results of differential manometer calibrations, a new formula was obtained which reduces its inaccuracy to 1% at pressures below 0.6 MPa. In addition, according to the pressure-energy diagrams, it was determined that the gas injection with excess pressures in the ejector suction chamber significantly increases the efficiency of the pumping-ejector system overall.

This chapter will cover the steps involved in folding the lens and preparing the lens for injection into the eye. Care must be taken not to touch the hydrophilic optic, to inject it through the correct wound size and to open it in the anterior chamber initially.

The effects of several operational parameters (pressure, temperature, CO2 flow rate, solution flow rate, injector type, and concentration of solute in the ethanol solution) during Supercritical AntiSolvent (SAS) precipitation process on the energy consumption cost per unit of manufactured product were investigated using experimental design technique. In this work, two different injectors were used. A completely randomized experiment would eventually require a modification of the apparatus after each experimental run. To avoid this, the experimental runs were done accordingly with a split-plot experimental design. For this study, Ibuprofen sodium salt was used as a model solute, ethanol was used as solvent, and CO2 was used as antisolvent. This supercritical fluid-based has been used successfully for several food and pharmaceutical applications since the production of small micro- and nanometer-sized particles have attracted growing interest in these industries. Focusing on energy saving, an SAS precipitation process was simulated using the SuperPro Designer simulation platform. The effect of temperature versus concentration of ethanolic solution and pressure versus solution flow rate interactions on the energy consumption cost per unit of manufactured product was demonstrated. The lowest estimated energy cost per unit of manufactured product was obtained using an ethanolic solution of 0.04 g mL−1 at 12 MPa of pressure and a solution flow rate of 1 mL min−1. This result was independent of the temperature. Thus, the present work reports a systematic energetic-economic study of the supercritical antisolvent micronization process, aiming increase knowledge about this process and its further incorporation by the food and pharmaceutical industries.

In computational fluid dynamics a lot of theoretical and numerical effort is made to have a method with the ability to correctly simulate fluid-structure interaction, free surfaces, as well as evolve multiple components and phases within a system. Traditionally, commercial and open source software is based on meshes where the implementation of open boundaries and interfaces is not trivial. A particle method, the Smooth Particle Hydrodynamics (SPH), has the advantage of being mesh free and the ability to treat open surfaces. This paper presents a study of the characteristics and capacity of the GPUSPH open source software to simulate a fluid injection through a fork injector submerged in a tank. The objective of this system is to study the formation of vortices and the oscillations of the free surface in the tank, an open problem in continuous metal casting industry. A system similar to that described by [3] and [12] has been simulated to study the velocity field inside the tank and compare with previous results. Our fiducial simulation reproduce the qualitative behavior observed in physical and numerical experiments [3, 4, 5, 6, 7, 8, 9, 12]. However, in order to reproduce the dynamics of water near the nozzle more than a million particles are required leading to somewhat higher computational cost in comparison to the mesh based methods.

A microjet with a maximum speed of 300 m/s and a diameter of 150 μm is ejected from a nozzle by the pulsed laser-induced bubble expansion. At every pulse of laser irradiation in the driving chamber, adverse air bubble growth has been a major issue in sustaining a uniform jet speed and overall performance of drug delivery. Here, a check valve is introduced to the drug chamber for controlling the flow dynamics inside and thus preventing ambient air from entering the nozzle. The newly designed valve in the laser-induced microjet injector proves that constant jet speed is possible regardless of the number of laser pulses, which allows the penetration of porcine skin to reach a depth well beyond 1.5–2.25 times the previously attained depths.

Supersonic gaseous ejector is practically a supersonic confined jet, where the primary supersonic jet flows through the confined passage and thereby entrains the secondary flow from the ambient. In this paper, the flow field of the supersonic gaseous ejector is investigated prominently using 2D-PIV measurement technique to study the mixing progression between the primary and the secondary flow at different operating conditions. A rectangular supersonic gaseous ejector (air-air) of low area ratio (AR = 3.7) is used in this study. Two separate supersonic primary flow nozzles of design, Mach number (MPD) 2.0 and 2.5, are considered in this experimentation. Differences between the supersonic free jet and the supersonic ejector or confined jet on the aspects of flow mixing are brought out clearly regarding flow kinematics. Centerline velocity decay, vorticity field, and wall static pressure distribution are used in parallel to explain the mixing progression in the ejector. Influence of the nozzle operating conditions on the gaseous mixing process is found to be prominent. Even a moderately underexpanded primary jet in a low AR supersonic ejector is observed to mix faster due to larger vorticity generation and early interaction of the mixing layer with the confined passage.

In order to support sustainable powertrain concepts, synthetic fuels show significant potential to be a promising solution for future mobility. It was found that \(\mathrm {CO_2}\) emissions during the combustion process of synthetic fuels can be reduced compared to conventional fuels and that sustainable fuel production pathways exists. Furthermore, it is possible to burn some synthetic fuels soot-free, which indirectly also eliminates the well-known soot-\(\mathrm {NO}_x\) tradeoff. However, in order to use the full potential of the new fuels, optimization of currently used injection systems needs to be performed. This is still challenging since fundamental properties are not known and pollutant formation is a multi-physics, multi-scale process. Therefore, the high-fidelity simulation framework CIAO is improved and optimized for predictive simulations of multiphase, reactive injections in complex geometries. Due to the large separation of scales, these simulations are only possible with current supercomputers. This work discusses the computational performance of the high-fidelity simulations especially focusing on vectorization, scaling, and input/output (I/O) on Hazel Hen (Cray XC40) supercomputer at the High Performance Computing Center Stuttgart (HLRS). Moreover, the impact of different internal nozzle flow initial conditions is shown, the effect of different chemical mechanisms studied, and the predictability of soot emissions investigated. The Spray A case defined by the Engine Combustion Network (ECN) is used as the target case due to the availability of experimental data for this injector.

The present paper analyses a gas ejector flow in a transition regime and requirements are formulated to experimental data suitable for numerical experiment. A single-stage axisymmetric supersonic ejector is considered. A flow transition regime feature is low-frequency pressure pulsations connected with periodic shock-train separation point displacement. Pressure oscillations are similar to those of damping oscillator with variable mass. The so-called ejector pressure ‘hysteresis’ is considered. This phenomenon should be used for gas saving to provide minimal vacuum chamber pressure level. There are the same ‘hysteresis’ and pressure pulsations in variable-shape nozzles, which is of space engineering concern.The natural experiments also showed the minimal vacuum chamber pressure to conform to minimal high-frequency ejector noise level. The ejector flow from start to a steady-state regime was simulated by both software FlowVision and original code. A numerical experiment gives acceptable average flow parameters and absolutely inacceptable low-frequency characteristics. The work has been performed supported by RFBI Grant No. 16-38-60185.

Using low-grade thermal energy instead of electricity to operate a refrigeration system can have important environmental benefits, especially when it is powered by a renewable energy source. Ejector refrigeration is one of the most promising technologies because of its relative simplicity and low capital cost when compared to an absorption refrigerator. An ejector heat pump is a heat-operated cycle capable of utilizing solar energy, waste energy, natural gas or hybrid sources (e.g. solar/gas). An ejector system basically consists of a generator, evaporator, condenser, ejector, expansion valve, and a pump. The ejector system has very few moving parts and so is simple in design. In addition, it has the potential of long life and, unlike vapour-compression systems, produces no noise or vibration. The system could be manufactured at relatively low cost, since inexpensive construction materials may be used. Although they have a relatively low coefficient of performance compared to air-conditioning systems using mechanical compressors, the ejector cooling technologies have attracted extensive attentions with ever-increasing awareness and pressures for protecting the environment and have achieved significant improvement in coefficient of performance as compared to other systems. The continuous developments in solar collector technology open the way to the effective utilization of solar energy to power the ejector systems and utilization of environmental friendly refrigerants is also the major concern. This chapter introduces the principle of the ejector, basic ejector cycle, solar-driven ejector system and its operating. The refrigerants, solar collectors, and PCM heat storage for solar ejector system applications are also introduced. A complete solar ejector air-conditioning system used in a building is presented in this chapter.

This study proposes a technique called intelligent well completions which uses water injection to improve sweep efficiency and recovery factor in oil production. The application of the technique in a water-flooding operation aims to optimize the outflow control valve (OCV) settings and injection rate of each segment of the oil production reservoir. A dynamic reservoir model was built using a reservoir flow performance simulator. It was observed that smart injection wells yield a better sweep efficiency with a favourable mobility ratio and improved pressure maintenance leading to an increase in field oil efficiency (FOE) when compared to the conventional wells and overall increase in net present value (NPV). In addition, the reservoir field oil efficiency was increased by 5% using the proposed technique.

It has been experimentally established that the modification of the spray nozzle structure of the diesel fuel injector due to the reduction of the length from 18 mm to 10 mm and the diameter from 6 mm to 4 mm of the precision guide, the increase in the diameter of the needle rod to increase its rigidity, the development of the cooling cavity under the differential needle pad increasing the number of fuel supply channels from 3 to 5, increasing the fuel injection pressure from 21–22 MPa to 27–28 MPa and reducing the needle stroke from 0.45 mm to 0.35 mm affects the power and economic parameters of tractor dies spruce. The use of experimental sprayers in a tractor diesel with gas turbine supercharging makes it possible to reduce the specific fuel consumption by 2–6 g/kW h and the temperature of the exhaust gases by 30–50 °C depending on the loading regime, as well as some increases (up to 2%) the coefficient of adaptability for torque. Using sprayers of experimental design in diesel with gas turbine supercharging allows to reduce the specific effective fuel consumption by 2–6 g/kW h and exhaust gas temperature by 30–50 °C depending on the loading mode, also some increase (up to 2%) of the coefficient of adaptability for the torque is registered.