Mixing process and nucleation of an Al-Si alloy during controlled diffusion solidification with simultaneous mixing and effect of mixing rate

2022 ◽  
Author(s):  
T. J. Chen ◽  
X. K. Yang ◽  
H. Xue ◽  
G. L. Bi ◽  
X. Z. Zhang ◽  
...  
Keyword(s):  
Mixing Process ◽  
Mixing Rate ◽  
Controlled Diffusion

Optimization of Multiple Jets Mixing With a Confined Crossflow

1997 ◽  
Vol 119 (2) ◽  
pp. 315-321 ◽  
Author(s):  
Th. Doerr ◽  
M. Blomeyer ◽  
D. K. Hennecke
Keyword(s):  
Temperature Distribution ◽  
Momentum Flux ◽  
Flux Ratio ◽  
Mixing Process ◽  
Mixing Rate ◽  
Mixing Processes ◽  
Jet Mixing ◽  
Momentum Flux Ratio ◽  
Jet In Crossflow ◽  
Geometric Conditions

An experimental investigation of a nonreacting multiple jet mixing with a confined crossflow has been conducted. Flow and geometric conditions were varied in order to examine favorable parameters for mixing. The requirement for a rapid and intense mixing process originates from combustion applications, especially the RQL-combustion concept. Thus, the jets were perpendicularly injected out of one opposed row of circular orifices into a heated crossflow in a rectangular duct. Spacing and hole size were varied within the ranges referring to combustor applications. The results presented are restricted to an in-line orientation of opposed jet axis. Temperature distribution, mixing rate, and standard deviation were determined at discrete downstream locations. Best, i.e., uniform mixing can be observed strongly depending on momentum flux ratio. For all geometries investigated, an optimum momentum flux ratio yields to a homogeneous temperature distribution in the flow field downstream of the injection plane. Overly high ratios deteriorate the mixing process due to the mutual impact of the opposed entraining jets along with a thermal stratification of the flowfield. Correlations are introduced describing the dependency of optimum momentum flux ratio on mixing hole geometry. They allow the optimization of jet-in-crossflow mixing processes in respect to uniform mixing.

Optimization of Multiple Jets Mixing With a Confined Crossflow

1995 ◽  
Author(s):  
Th. Doerr ◽  
M. Blomeyer ◽  
D. K. Hennecke
Keyword(s):  
Temperature Distribution ◽  
Momentum Flux ◽  
Flux Ratio ◽  
Mixing Process ◽  
Mixing Rate ◽  
Mixing Processes ◽  
Jet Mixing ◽  
Momentum Flux Ratio ◽  
Jet In Crossflow ◽  
Geometric Conditions

An experimental investigation of a non-reacting multiple jet mixing with a confined crossflow has been conducted. Flow and geometric conditions were varied in order to examine favourable parameters for mixing. The requirement for a rapid and intense mixing process originates from combustion applications, especially the RQL-combustion concept. Thus, the jets were perpendicularly injected out of one opposed row of circular orifices into a heated crossflow in a rectangular duct. Spacing and hole size were varied within the ranges referring to combustor applications. The results presented are restricted to an inline orientation of opposed jet axis. Temperature distribution, mixing rate and standard deviation were determined at discrete downstream locations. Best i.e. uniform mixing can be observed strongly depending on momentum flux ratio. For all geometries investigated an optimum momentum flux ratio yields to a homogeneous temperature distribution in the flowfield downstream of the injection plane. Too high ratios deteriorate the mixing process due to the mutual impact of the opposed entraining jets along with a thermal stratification of the flowfield. Correlations are introduced describing the dependency of optimum momentum flux ratio on mixing hole geometry. They allow the optimization of jet-in-crossflow mixing processes in respect to uniform mixing.

scholarly journals MIXING RATE OF PHOSPHATE BETWEEN PLASMA AND INTERSTITIAL BODY FLUID OF COWS

1950 ◽  
Vol 33 (5) ◽  
pp. 525-534 ◽  
Author(s):  
Max Kleiber ◽  
Arthur H. Smith ◽  
N. P. Ralston
Keyword(s):  
Jugular Vein ◽  
Mixing Time ◽  
Turnover Time ◽  
Interstitial Tissue ◽  
Tissue Fluid ◽  
Mixing Process ◽  
Order Process ◽  
Plasma Phosphate ◽  
Mixing Rate ◽  
First Order

Radiophosphate was injected into the left jugular vein of dairy cows. Blood samples were taken frequently from the right jugular vein during the first hour after injection. Between 20 minutes and 1 hour after injection, the decrease in plasma radioactivity could be formulated as a first order process, designated as "process 3," with a turnover time of 50 minutes. From 5 to 20 minutes after injection the decrease in plasma activity could be interpreted as the result of mixing plasma phosphate with another phosphate pool, designated as the second pool. The capacity of this second pool was derived as a constant in a kinetic equation, so chosen that the resulting mixing rates were independent of time. For two cows the capacity of the second pool was 5 and 8 times, respectively. the phosphate content of the plasma. This result led to the working hypothesis that the major part of the second pool was the phosphate in the interstitial tissue fluid. The turnover time of the plasma phosphate in the mixing process with the second pool amounted to an average of 14 minutes for 5 lactating cows, and an average of 21 minutes for 2 dry cows. This result was obtained under the assumption that the slow first order process 3 is parallel to the mixing process. The assumption that the slower first order process is in series with the mixing process reduces the resulting mixing time to about four-fifths of that reported above. The calculation of process 2 which deviates from first order may be applicable to numerous turnover processes in which both exchange pools have a limited capacity.

scholarly journals Numerical Simulation of Mixing Process in a Splitting-and-Recombination Microreactor

2022 ◽  
Vol 3 ◽  
Author(s):  
Lifang Yan ◽  
Shiteng Wang ◽  
Yi Cheng
Keyword(s):  
Reynolds Numbers ◽  
Mixing Efficiency ◽  
Horizontal Distance ◽  
Mixing Process ◽  
Mixing Rate ◽  
Navier Stokes Equation ◽  
Vertical Distance ◽  
Wide Range ◽  
Spacing Distance ◽  
Comb Tooth

The mixing process between miscible fluids in a splitting-and-recombination microreactor is analyzed numerically by solving the Navier–Stokes equation and species transfer equation. The commercial microreactor combines rectangular channels with comb-shaped inserts to achieve the splitting-and-recombination effect. The results show that the microreactor with three-layer standard inserts have the highest mixing rate as well as good mixing efficiency within a wide range of Reynolds numbers from 0.1 to 160. The size parameters of the inserts, both the ratio of the width of comb tooth (marked as l) and the spacing distance (marked as s) between two comb teeth, and the ratio of the vertical distance (marked as V) of comb teeth and the horizontal distance (marked as H) are essential for influencing the liquid–liquid mixing process at low Reynolds numbers (e.g., Re ≤ 2). With the increase of s/l from 1 to 4, the mixing efficiency drops from 0.99 to 0.45 at Re = 0.2. Similarly, the increase in V/H is not beneficial to promote the mixing between fluids. When the ratio of V/H changes from 10:10 to 10:4, the splitting and recombination cycles reduce so that the uniform mixing between different fluids can be hardly achieved. The width of comb tooth (marked as l) is 1 mm and the spacing distance (marked as s) between two comb teeth is 2 mm. The vertical distance (marked as V) of comb teeth and the horizontal distance (marked as H) are both 10 mm.

Study on Hypereutectic Al-Si Alloy Fabricated by Liquid-Liquid Mixing

2013 ◽  
Vol 815 ◽  
pp. 13-18
Author(s):  
Yuan Dong Li ◽  
Shao Hua Hu ◽  
Xia Li ◽  
Ming Tao He ◽  
Ying Ma ◽  
...  
Keyword(s):  
High Temperature ◽  
Primary Silicon ◽  
Primary Phase ◽  
Mixing Process ◽  
High Temperature Alloy ◽  
Pouring Temperature ◽  
Controlled Diffusion ◽  
Fine Grain ◽  
Liquid Mixing ◽  
Morphology Changes

The hypereutectic Al-20%Si alloy was fabricated by liquid-liquid mixing of Controlled Diffusion Solidification (CDS), and the mixing interface of two precursor alloys as well as the effects of pouring temperature during liquid-liquid mixing process on microstructure of size, morphology and distribution of primary silicon were studied. The results show that the size of primary phase decreases as the pouring temperature decreases, and the distribution of primary phase becomes uniform, but the morphology changes unobvious. Meanwhile, the liquid-liquid mixing interface is divided into four areas: low temperature alloy area, interface front area, fine grain area and high temperature alloy area.

GPU-Based Simulation on Particle Mixing in a Tote Blender

2012 ◽  
Vol 549 ◽  
pp. 918-923 ◽  
Author(s):  
Xin Xin Ren ◽  
Li Jie Cui ◽  
Wei Ge
Keyword(s):  
Computer Simulation ◽  
Large Scale ◽  
Solid Particles ◽  
Mixing Process ◽  
Experiment Data ◽  
Mixing Rate ◽  
Reliable Tool ◽  
Operation Conditions ◽  
Particle Mixing ◽  
Good Agreement

The mixing of dry solid particles is extremely important for pharmaceutical and chemical industries. Computer simulation is a convenient way to study the microscopic mixing process. In this paper, a GPU-based DEM software is tested in large-scale simulation of a tote blender by comparing with experiment data from literature and then employed to study the effects of operation conditions on the mixing rate. The results are in good agreement with experiments, confirming that the GPU-based DEM software is an effective and reliable tool for the study of micro-dynamics in particles mixing.

Performance Analysis and Parameter Optimization of a Planetary Mixer

2010 ◽  
Vol 37-38 ◽  
pp. 858-861 ◽  
Author(s):  
Ming Jin Yang ◽  
Xi Wen Li ◽  
Tie Lin Shi ◽  
Shu Zi Yang
Keyword(s):  
Performance Analysis ◽  
Parameter Optimization ◽  
Mixing Time ◽  
Parameters Optimization ◽  
Fluid Mixing ◽  
Speed Ratio ◽  
Mixing Process ◽  
Mixing Rate ◽  
Revolution Speed ◽  
Kinematical Parameters

According to axial symmetry of geometric and kinematical features of the mixing domain of a planetary mixer, definitions of impact factor of crossing, mixing rate and mixing time were put forward for the performance analysis and parameter optimization of the mixer. It was found that the speed ratio of rotation and revolution of the screw blades has strong influence on the mixing process. An optimum revolution speed was obtained on conditions of the speed ratio of rotation and revolution being constant. The fluid mixing system in the mixing tank can be optimized through geometric and kinematical parameters optimization.

scholarly journals Optimum Mixing for a Two-Sided Injection From Opposing Rows of Staggered Jets Into a Confined Crossflow

1996 ◽  
Author(s):  
Malte M. Blomeyer ◽  
Bernd H. Krautkremer ◽  
Dietmar K. Hennecke
Keyword(s):  
Momentum Flux ◽  
Flux Ratio ◽  
Diameter Ratio ◽  
Mixing Process ◽  
Rectangular Duct ◽  
Mixing Rate ◽  
Lean Burn ◽  
Key Technology ◽  
Geometric Conditions ◽  
The Rich

The injection of jets normal to a crossflow is a key technology for the development of an advanced low NOx gas turbine based on a Rich-Burn/Quick-Quench/Lean-Burn (RQL) combustor. The RQL combustor depends on an efficient quick mix section that rapidly and uniformly dilutes the rich zone products to minimize emissions. Therefore, an experimental investigation of a non-reacting mixing process of jets in a crossflow was conducted. The jets were perpendicularly injected through one stage of opposed rows of circular orifices into a slightly heated crossflow within a rectangular duct. All geometries were tested with staggered arrangements of the centerlines of the opposed jets. The temperature distribution was measured and from that the mixing rate was determined for parametric variations of flow and geometric conditions. In accordance with the application to RQL-combustion, emphasis was put on high momentum flux ratios with high massflow addition. The experimental study provides the data base for a correlation of best mixing depending on geometric conditions for staggered mixing configurations. The correlation presented specifies the optimum momentum flux ratio as a function of the duct height to hole diameter ratio and the relative spacing of the injected jets.

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