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Emission reduction and decarbonisation in the industry are crucial for low-carbon industry and energy transition at the global level. Replacing traditional fossil fuel with clean energy is an effective approach to reduce carbon emissions and optimize energy efficiency in manufacturing processes. Industrial kiln, which requires high natural gas fuel consumption, typically releases amounts of harmful combustion products. In this paper, the objective is to study the influence of hydrogen addition into methane-air jet flame in industrial kiln burners. The industrial burner analysed in this study is a cylinder vessel with axial orifices and swirl turbulent co-flow air jets in the fuel-air inlet structure. A more recent reduced chemical kinetic mechanism for methane-hydrogen combustion is utilized in the present flame simulation and validated in benchmark flames. The chemical mechanism involves 45 reactions and 18 species. Various methane-hydrogen blending fuels are studied in the jet flame, where flame structure and flame characteristics including chemical species, temperature, and velocity are predicted., Peer Reviewed, Postprint (published version)

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Impinging jet can be defined as a high-velocity coolant mass ejected from a hole or slot that impinges on the heat transfer surface. A characteristic feature of this flow arrangement is an intensive heat transfer rate between the application and the fluid. Jet impingement is an attractive cooling mechanism in which we are going to achieve maximum possible heat transfer rates. A confinement is provided to have recirculation of fluid resulting in more heat transfer. In following paper heat transfer characteristics of confined air jet impingement have been studied. It is found that for H/d ratio 6 maximum heat transfer takes place.

Proper selection and sizing of ventilation systems require knowledge of emissions from internal contaminant and heat sources and an understanding of the characteristics of air and contaminant movement. In this chapter, the major factors affecting air and contaminant movement inside ventilated space are summarized and classified as: (1) transport mechanism of contaminant in ventilated space; (2) contaminant sources; (3) forced convection or supply air jets introduced into the room by mechanical or natural ventilation systems, or their combination; (4) free convection flows along heated and cooled vertical surfaces and above heat sources; (5) airflow created in the vicinity of local and general exhausts; (6) aerodynamic means of large opening protection; and (7) airflow through intended and unintended openings and cracks in the building envelope. This chapter provides some guidance on how to select predominant factors affecting air and contaminant movement, account for their joint effects, and predict airflow characteristics., Part of ISBN 9780128167809 9780128167816QC 20230714

Shock wave boundary layer interactions (SWBLI) are a common phenomenon in transonic and supersonic flows. The presence of shock waves, induced by specific geometrical configurations, causes a rapid increase of the pressure, which can lead to flow separation. Examples of such interactions are found in amongst others rocket engine nozzles and on aerospikes, on re-entry vehicles, in supersonic and hypersonic engine intakes, and at the tips of compressor and turbine blades in jet engines. The interactions are important factors in vehicle development. Both the separated flow and the induced shock have been shown to be highly unsteady, causing pressure fluctuations and thermal loading. This generally leads to a degraded performance and possibly structural failure. The current work therefore aims to improve the physical understanding of the mechanisms that govern the interaction, with a special attention for the flow organisation and for the sources of the unsteadiness of the induced shock. In particular, the case of a reflecting incident shock is investigated, but the results find their application more generally in other configurations. Additionally, it is verified whether the interaction can be controlled by means of upstream fluid injection. To attain these aims, experiments were performed, comparing systematically several interactions for a range of shock intensities (producing incipiently separated and well separated flows) and under a number of flow conditions (Mach numbers of 1.7 and 2.3 and Reynolds numbers of 5,000 (‘low’) and 50,000 (‘high’)). This was done using the latest developments in the field of measurement techniques. A large amount of data was obtained for multiple interactions by means of a range of flow diagnostic techniques, yielding highly consistent results. A full field determination of the characteristic time scales by means of dual plane particle image velocimetry (Dual-PIV) has shown that the unsteadiness frequencies in the high Reynolds number, Aerospace Design, Integration & Operations, Aerospace Engineering

Shock wave boundary layer interactions (SWBLI) are a common phenomenon in transonic and supersonic flows. The presence of shock waves, induced by specific geometrical configurations, causes a rapid increase of the pressure, which can lead to flow separation. Examples of such interactions are found in amongst others rocket engine nozzles and on aerospikes, on re-entry vehicles, in supersonic and hypersonic engine intakes, and at the tips of compressor and turbine blades in jet engines. The interactions are important factors in vehicle development. Both the separated flow and the induced shock have been shown to be highly unsteady, causing pressure fluctuations and thermal loading. This generally leads to a degraded performance and possibly structural failure. The current work therefore aims to improve the physical understanding of the mechanisms that govern the interaction, with a special attention for the flow organisation and for the sources of the unsteadiness of the induced shock. In particular, the case of a reflecting incident shock is investigated, but the results find their application more generally in other configurations. Additionally, it is verified whether the interaction can be controlled by means of upstream fluid injection. To attain these aims, experiments were performed, comparing systematically several interactions for a range of shock intensities (producing incipiently separated and well separated flows) and under a number of flow conditions (Mach numbers of 1.7 and 2.3 and Reynolds numbers of 5,000 (‘low’) and 50,000 (‘high’)). This was done using the latest developments in the field of measurement techniques. A large amount of data was obtained for multiple interactions by means of a range of flow diagnostic techniques, yielding highly consistent results. A full field determination of the characteristic time scales by means of dual plane particle image velocimetry (Dual-PIV) has shown that the unsteadiness frequencies in the high Reynolds number, Aerospace Design, Integration & Operations, Aerospace Engineering

The 2D numerical model to simulate the pollutant dispersion and evaporation, when the air jet is used, was proposed. The results of numerical experiment are presented., На базе модели потенциального течения и модели переноса примеси предложена 2D численная модель для расчета процесса испарения от зоны разлива при подаче воздушной струи. Представлены результаты численного моделирования., На базі моделі потенціальної течії та моделі переносу домішки запропоновано 2D чисельна модель для прогнозування випарування від зони розливу при використанні струменя повітря. Наведено результати розрахунків на базі розробленої моделі.

A novel noncontact indentation system with the combination of an air jet and optical coherence tomography (OCT) was presented in this paper for the quantitative measurement of the mechanical properties of soft tissues. The key idea of this method is to use a pressure-controlled air jet as an indenter to compress the soft tissue in a noncontact way and utilize the OCT signals to extract the deformation induced. This indentation system provides measurement and mapping of tissue elasticity for small specimens with high scanning speed. Experiments were performed on 27 silicone tissue-mimicking phantoms with different Young's moduli, which were also measured by uniaxial compression tests. The regression coefficient of the indentation force to the indentation depth (N mm(-1)) was used as an indicator of the stiffness of tissue under air jet indentation. Results showed that the stiffness coefficients measured by the current system correlated well with the corresponding Young's moduli obtained by conventional mechanical testing (r = 0.89, p < 0.001). Preliminary in vivo tests also showed that the change of soft tissue stiffness with and without the contraction of the underlying muscles in the hand could be differentiated by the current measurement. This system may have broad applications in tissue assessment and characterization where alterations of mechanical properties are involved, in particular with the potential of noncontact micro-indentation for tissues.

The purpose of air distribution systems for HVAC is tocreate proper air quality and thermal conditions in an occupiedzone. In mixing type air distribution systems air is suppliedinto a room through various types of outlets and distributed byturbulent air jets. These air jets are the primary factorsaffecting room air motion. The ASHRAE handbook recognises fourmajor zones of maximum velocity decay along a jet. Although numerous theoretical and experimental studies havebeen conducted to develop turbulent air jet theory from the1930's, air jet performance in the further field from theoutlet is still not well understood. Many studies were therefore carried out, and the followingconclusions can be drawn from them: The end centerline velocities of zone 3 for both "free"jet and wall jet could strongly depend on the outletvelocities and room size. TheK-value of wall jets could be a function of bothoutlet velocities and outlet size. It is very important to choose suitable sampling time toevaluate jet performance. CFD can not always be used to predict jet behaviour,especially for the jet with low outlet velocity and in thearea far away from the outlet. However, for a two-dimensionwall jet, CFD could be a powerful tool for designers. KEYWORDS: air jet, centerline velocity,K-velocity, air diffuser, ventilation, measurement,CFD, NR 20140805

The purpose of air distribution systems for HVAC is tocreate proper air quality and thermal conditions in an occupiedzone. In mixing type air distribution systems air is suppliedinto a room through various types of outlets and distributed byturbulent air jets. These air jets are the primary factorsaffecting room air motion. The ASHRAE handbook recognises fourmajor zones of maximum velocity decay along a jet. Although numerous theoretical and experimental studies havebeen conducted to develop turbulent air jet theory from the1930's, air jet performance in the further field from theoutlet is still not well understood. Many studies were therefore carried out, and the followingconclusions can be drawn from them: The end centerline velocities of zone 3 for both "free"jet and wall jet could strongly depend on the outletvelocities and room size. TheK-value of wall jets could be a function of bothoutlet velocities and outlet size. It is very important to choose suitable sampling time toevaluate jet performance. CFD can not always be used to predict jet behaviour,especially for the jet with low outlet velocity and in thearea far away from the outlet. However, for a two-dimensionwall jet, CFD could be a powerful tool for designers. KEYWORDS: air jet, centerline velocity,K-velocity, air diffuser, ventilation, measurement,CFD, NR 20140805

The purpose of air distribution systems for HVAC is tocreate proper air quality and thermal conditions in an occupiedzone. In mixing type air distribution systems air is suppliedinto a room through various types of outlets and distributed byturbulent air jets. These air jets are the primary factorsaffecting room air motion. The ASHRAE handbook recognises fourmajor zones of maximum velocity decay along a jet. Although numerous theoretical and experimental studies havebeen conducted to develop turbulent air jet theory from the1930's, air jet performance in the further field from theoutlet is still not well understood. Many studies were therefore carried out, and the followingconclusions can be drawn from them: The end centerline velocities of zone 3 for both "free"jet and wall jet could strongly depend on the outletvelocities and room size. TheK-value of wall jets could be a function of bothoutlet velocities and outlet size. It is very important to choose suitable sampling time toevaluate jet performance. CFD can not always be used to predict jet behaviour,especially for the jet with low outlet velocity and in thearea far away from the outlet. However, for a two-dimensionwall jet, CFD could be a powerful tool for designers. KEYWORDS: air jet, centerline velocity,K-velocity, air diffuser, ventilation, measurement,CFD, NR 20140805

The purpose of air distribution systems for HVAC is tocreate proper air quality and thermal conditions in an occupiedzone. In mixing type air distribution systems air is suppliedinto a room through various types of outlets and distributed byturbulent air jets. These air jets are the primary factorsaffecting room air motion. The ASHRAE handbook recognises fourmajor zones of maximum velocity decay along a jet. Although numerous theoretical and experimental studies havebeen conducted to develop turbulent air jet theory from the1930's, air jet performance in the further field from theoutlet is still not well understood. Many studies were therefore carried out, and the followingconclusions can be drawn from them: The end centerline velocities of zone 3 for both "free"jet and wall jet could strongly depend on the outletvelocities and room size. TheK-value of wall jets could be a function of bothoutlet velocities and outlet size. It is very important to choose suitable sampling time toevaluate jet performance. CFD can not always be used to predict jet behaviour,especially for the jet with low outlet velocity and in thearea far away from the outlet. However, for a two-dimensionwall jet, CFD could be a powerful tool for designers. KEYWORDS: air jet, centerline velocity,K-velocity, air diffuser, ventilation, measurement,CFD, NR 20140805