Experimental investigation was carried out for gas-liquid slug flow in vertical and inclined tubes. The non- Invasive measurements of the gas-liquid slug flow were taken by using the EKTAPRO 1000 High Speed Motion Ana...
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In this paper,the least-squares method is used to solve the Inverse Heat Conduction Problem(IHCP)to determine the space-wise variation of the unknown boundary condition on the inner surface of a helically coiled tube ...
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In this paper,the least-squares method is used to solve the Inverse Heat Conduction Problem(IHCP)to determine the space-wise variation of the unknown boundary condition on the inner surface of a helically coiled tube with fluid flow inside,electrical heating and insulation *** sensitivity coefficient is analyzed to give a rational distribution of the thermocouples. The results demonstrate that the method effectively extracts information about the unknown boundary condition for the heat conduction problem from the experimental measurements. The results also show that the least-squares method converges very quickly.
An investigation on the high-quality dryout in two electrically heated coiled tubes with horizontally helix axes is reported. The temperature profiles both along the tube and around the circumference are measured, and...
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An investigation on the high-quality dryout in two electrically heated coiled tubes with horizontally helix axes is reported. The temperature profiles both along the tube and around the circumference are measured, and it is found that the temperature profiles around the circumference are not idelltical for the cross-sections at different parts of the coil. The 'local condition hypothesis' seems applicable under present conditions, and the critical heat flux qcr decreases with increasing critical quality xcr The CHF increases as mass velocity and ratio of tube diameter to coil diameter (d/D) increases, and it seems not to be effected by the system pressure. The CHF is larger with coils than that with straight tubes, and the difference increases with increasing mass velocity and d/D.
The transient two-fluid model has been used to develop a general relation for acoustic waves. The analysis is valid in principle over the whole void fraction region. flow pattern transitions from one flow regime to th...
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The transient two-fluid model has been used to develop a general relation for acoustic waves. The analysis is valid in principle over the whole void fraction region. flow pattern transitions from one flow regime to the other are assumed to occur at certain void fractions. Different correlations are used to calculate the interfacial area and interfacial drag force per unit mixture volume for bubbly flow,slug flow and annular flow respectively. The Vapour-liquid interphase heat flux is derived from the one dimensional Fourier heat conduction equation to evaluate the interphase evaporation or condensatior *** on the present theory, a program has been carried out. Calculations are performed for pressure from 0.07 MPa to 16.0 MPa, void fractions from 0.0 to 1.0. The predicted sound speeds are compare with some experimental data for low pressures, good agreement has been achieved between sound speed predictions and experimental data.
This review covers three decades of research on mesoscale phenomena in chemical engineering, from the energy minimization multiscale (EMMS) model specific for gas–solid fluidization to a general principle of compromi...
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This review covers three decades of research on mesoscale phenomena in chemical engineering, from the energy minimization multiscale (EMMS) model specific for gas–solid fluidization to a general principle of compromise in competition between dominant mechanisms, leading to the proposed concept of mesoscience. First, the concept of mesoscales is reviewed with respect to their commonality, diversity, and misunderstanding in different fields. Then, the evolution from the EMMS model to the EMMS principle common to all mesoscales is described to show the rationale of mesoscience referring to both mesoscales and mesoregimes. Finally, the potential universality of mesoscience and its importance, particularly to enable virtual process engineering (VPE) by realizing the consistency of logic and structure between the problem, the model, the software, and the computer, are discussed. The review concludes by illustrating possible case studies to collect more evidence and a potential framework for mesoscience.
This review discusses the complex behaviors in diverse chemical and biochemical systems to elucidate their commonalities and thus help develop a mesoscience methodology to address the complexities in even broader topi...
This review discusses the complex behaviors in diverse chemical and biochemical systems to elucidate their commonalities and thus help develop a mesoscience methodology to address the complexities in even broader topics. This could possibly build a new scientific paradigm for different disciplines and could meanwhile provide effective tools to tackle the big challenges in various fields, thus paving a path toward combining the paradigm shift in science with the breakthrough in technique developments. Starting with our relatively fruitful understanding of chemical systems, the discussion focuses on the relatively pristine but very intriguing biochemical systems. It is recognized that diverse complexities are multilevel in nature, with each level being multiscale and the complexity emerging always at mesoscales in mesoregimes. Relevant advances in theoretical understandings and mathematical tools are summarized as well based on case studies, and the convergence between physics and mathematics is highlighted.
In the context of rising adverse effects of climate change on agriculture, there is a need for advanced methods and practices to manage soils for production of food and energy. This book presents the latest advances i...
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ISBN:
(数字)9783031241819
ISBN:
(纸本)9783031241802;9783031241833
In the context of rising adverse effects of climate change on agriculture, there is a need for advanced methods and practices to manage soils for production of food and energy. This book presents the latest advances in microbial processes that control plant growth, with focus on genomic tools, microbial interactions with the plant and soils habitats, mobilization of plant nutrients, agricultural waste management, biodegradation, bioremediation, carbon sequestration, land reclamation, plant growth promotion, suppression of plant pathogens, induced systemic resistance and tolerance against biotic and abiotic stresses.
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