Non-Volatile Fraction Effects in Dispersed Vacuum Spray Flash Evaporation

2020 ◽  
Author(s):  
Guangyu Guo ◽  
Hongling Deng ◽  
Chao Zhu ◽  
Zhiming Ji
Keyword(s):  
Experimental System ◽  
Spray Cooling ◽  
Volatile Fraction ◽  
Transfer Enhancement ◽  
Flash Evaporation ◽  
Liquid Residue ◽  
Two Phases ◽  
Set Up ◽  
Good Agreement ◽  
Non Equilibrium

Abstract Spray flash evaporation has been widely used in spray cooling and thermal distillation as a technology of heat/mass transfer enhancement. In a vacuum spray flash process, the vapor is instantly extracted by vacuuming, while the supersaturated droplets are further cooled by the continued spray flash until becoming saturated or discharged. Hence, in the evaporator, non-equilibrium exists not only in the flash evaporation driven by the pressure difference between droplet and ambient but also in the temperatures of yields, namely, generated vapor and discharged liquid with or without precipitates. To deeper understand such interesting thermal non-equilibrium between two phases in a spray flash evaporation of salty water, this paper establishes a multi-component spray flash evaporation model which coupled with diffusivity effect of non-volatile fraction, as well as the influence of spray polydispersion. An experimental system is also set up for evaporative coefficient determination, as well as model validation. The theoretical and experimental results meet a good agreement. It indicates the salinity and the superheat level of inlet feed have substantial impacts on such thermal non-equilibrium phenomenon of the temperature difference between the extracted vapor and the discharged liquid residue.

Dynamic Behavior Analysis of the Slider Crank Linkage using ANSYS Workbench and MATLAB Program

2013 ◽  
Vol 1 (1) ◽  
pp. 42-25
Author(s):  
Nabil N. Swadi
Keyword(s):  
Graphical Method ◽  
Joint Torque ◽  
Pressure Force ◽  
Matlab Program ◽  
Element Simulation ◽  
Acceleration Method ◽  
Complete Revolution ◽  
Two Phases ◽  
Good Agreement ◽  
Ansys Workbench

This paper is concerned with the study of the kinematic and kinetic analysis of a slider crank linkage using D'Alembert's principle. The links of the considered mechanism are assumed to be rigid. The analytical solution to observe the motion (displacement, velocity, and acceleration), reactions at each joint, torque required to drive the mechanism and the shaking force have been computed by a computer program written in MATLAB language over one complete revolution of the crank shaft. The results are compared with a finite element simulation carried out by using ANSYS Workbench software and are found to be in good agreement. A graphical method (relative velocity and acceleration method) has been also applied for two phases of the crank shaft (q2 = 10° and 130°). The results obtained from this method (graphical) are compared with those obtained from analytical and numerical method and are found very acceptable. To make the analysis linear the friction force on the joints and sliding interface are neglected. All results, in this work, are obtained when the crank shaft turns at a uniform angular velocity (w2 = 188.5 rad/s) and time dependent gas pressure force on the slider crown.

scholarly journals Laboratory Measurements of Light Scattering by Dust Particles

1996 ◽  
Vol 150 ◽  
pp. 409-413
Author(s):  
Patrick P. Combet ◽  
Philippe L. Lamy
Keyword(s):  
Light Scattering ◽  
Laser Beam ◽  
Mie Theory ◽  
Spherical Particles ◽  
Dust Particles ◽  
Laboratory Measurements ◽  
Scattering Function ◽  
Hene Laser ◽  
Set Up ◽  
Good Agreement

AbstractWe have set up an experimental device to optically study the scattering properties of dust particles. Measurements over the 8 — 174° interval of scattering angles are performed on a continuously flowing dust loaded jet illuminated by a polarized red HeNe laser beam. The scattering is averaged over the population of the dust particles in the jet, which can be determined independently, and give the “volume scattering function” for the two directions of polarization directly. While results for spherical particles are in good agreement with Mie theory, those for arbitrary particles show conspicuous deviations.

The Reduction of Bias Error in Transfer Function Estimates Using FFT-Based Analyzers

1984 ◽  
Vol 106 (1) ◽  
pp. 29-35 ◽  
Author(s):  
P. Cawley
Keyword(s):  
Transfer Function ◽  
Random Excitation ◽  
Analogue Computer ◽  
Bias Error ◽  
Testing Time ◽  
Theoretical Predictions ◽  
Set Up ◽  
Modal Mass ◽  
Time Required ◽  
Good Agreement

The susceptibility to bias error of two methods for computing transfer (frequency response) functions from spectra produced by FFT-based analyzers using random excitation has been investigated. Results from tests with an FFT analyzer on a single degree-of-freedom system set up on an analogue computer show good agreement with the theoretical predictions. It has been shown that, around resonance, the bias error in the transfer function estimate H2 (Syy/Sxy*) is considerably less than that in the more commonly used estimate, H1 (Sxy/Sxx). The record length, and hence the testing time, required for a given accuracy is reduced by over 50 percent if the H2 calculation procedure is used. The analysis has also shown that if shaker excitation is used on lightly damped structures with low modal mass, it is important to minimize the mass of the force gage and the moving element of the shaker.

Study the Relative Permeability of Ferrofluid with the Mean Value Analysis of Experimental Apparent Gravity

2011 ◽  
Vol 194-196 ◽  
pp. 533-536
Author(s):  
Je Ee Ho
Keyword(s):  
Relative Permeability ◽  
Magnetic Characteristic ◽  
Physical Property ◽  
Experimental System ◽  
Mean Value ◽  
Efficient Operation ◽  
Value Analysis ◽  
Implicit Model ◽  
Drastic Increase ◽  
Set Up

Relative permeability is an important magnetic characteristic for ferrofluid to exhibit its magnetized potential during the magnetization process. To understand above physical property varying with field intensity, a popular analytic model, based on Langevin theory, has been usually considered and widely used. Unfortunately, an implicit model, derived from above hypothesis, for solving the instantaneous magnetization of ferro-particle will be carried out unless the determination of saturated magnetization should be conducted in advance. Just for the study dealing with magnetic property of testing ferro-sample is concerned, the previous acquisition of magnetization curve is impossible and unpractical without the precise measurement of magnetization-degree. On the other hand, required experimental expense is still so costly that it seems to be unaffordable for general laboratory. Thus a self-designed electromagnetic mechanism with special facility of smaller size, economical cost and efficient operation to quantify the reduced gravity of ferro-sample attracts our interest and is set up in this study. Meantime, an auxiliary numerical method, Newton interpolatory divided-difference formulas in trapezoidal rule, involved in this study successfully avoids the essentiality of saturated magnetization determined previously, and which also provides a numerical approximation through the weight loss of ferrofluid experienced by the designed experimental system. As compared with the result measured by VSM (vibration sample magnetometer) method, the estimated profile shows an excellent agreement except the extraordinary outcome occurring at B=6 mT, where a drastic increase of relative permeability will be evaluated due to the faster magnetization starts.

Simulating the behaviour of folded cartons during complex packing operations

2006 ◽  
Vol 220 (12) ◽  
pp. 1797-1811 ◽  
Author(s):  
D M Sirkett ◽  
B J Hicks ◽  
C Berry ◽  
G Mullineux ◽  
A J Medland
Keyword(s):  
End Users ◽  
Fundamental Issue ◽  
Trial And Error ◽  
Machine Material ◽  
Packaging Machine ◽  
Set Up ◽  
Fine Tune ◽  
Responsiveness To Change ◽  
Lower Production ◽  
Good Agreement

The folding carton is a widely used packaging solution. Recent European Union packaging legislation has forced carton manufacturers to use lighter-weight grades of carton board. This typically results in a reduction in board stiffness, which can lead to decreased process efficacy or even prevent successful processing. In order to overcome this, end-users lower production rates and fine-tune packaging machine settings for each pack and material. This trial-and-error approach is necessary because the rules relating machine set-up to pack design and material properties are not generally well known. The present study addresses this fundamental issue through the creation of a finite-element computer simulation of carton processing. Mechanical testing was performed to ascertain the key mechanical properties of the carton walls and creases. The carton model was validated against the experimental results and was then subjected to the machine-material interactions that take place during complex packaging operations. The overall approach was validated and the simulation showed good agreement with the physical system. The results of the simulation can be used to determine guidelines relating machine set-up criteria to carton properties. This will improve responsiveness to change and will ultimately allow end-users to process thinner lighter-weight materials more effectively.

Continuous Cultures of Plasmodium Falciparum Established in Tanzania From Patients With Acute Malaria

2021 ◽  
Author(s):  
Florence Humphrey Urio ◽  
Matilda Mkombachepa ◽  
Gration Rwegasira ◽  
Twilumba Makene ◽  
Billy Ngasala ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Continuous Culture ◽  
Drug Sensitivity ◽  
Culture Media ◽  
Experimental System ◽  
Dar Es Salaam ◽  
Clinical Samples ◽  
Host Cell Interactions ◽  
Set Up

Abstract BackgroundMalaria morbidity and mortality, almost entirely from Plasmodium falciparum, are still rampant in Africa: therefore, it is important to study the biology of the parasite and the parasite-host cell interactions. In vitro cultivation of Plasmodium falciparum is most useful for this purpose, as well as for investigating drug resistance and possible new therapies. Here we report that the Trager & Jensen continuous culture of P. falciparum can be established in a laboratory in Tanzania with minimal facilities and with modest expenditure.MethodsAn in vitro set-up of continuous culture of P. falciparum was carried out in 2016 to 2020 at Muhimbili university of health and allied sciences, Dar-es salaam. Parasite samples were obtained from patients with acute malaria, frozen parasites and live cultures. Data was collected and analyzed using GraphPad Prism version 8.ResultsWe have successfully achieved exponential growth of existing strains that are used worldwide, as well as of parasites in clinical samples from patients with acute malaria. In the aim to optimize growth we have compared human serum and bovine serum albumin as components of the culture media. In addition, culture synchronization has been achieved using sorbitol.ConclusionThis experimental system is now available to our institution and to researchers aiming at investigating drug sensitivity and mechanisms of protection against Plasmodium falciparum that accrue from various genes expressed in red cells.

Numerical Simulation of Compressive Residual Strength for Damaged Composite Laminates

2012 ◽  
Vol 525-526 ◽  
pp. 385-388
Author(s):  
Tian Jiao Qu ◽  
Xi Tao Zheng ◽  
Di Zhang
Keyword(s):  
Composite Laminates ◽  
Impact Test ◽  
Compressive Load ◽  
Low Velocity Impact ◽  
Fiber Breakage ◽  
Low Velocity ◽  
Appearance Time ◽  
Finite Element Software ◽  
Set Up ◽  
Good Agreement

After the low-velocity impact test of composite laminates of T800/BA9916, CAI test and compression test of laminates with a hole have been carried out. Two types of models were set up by the finite element software ABAQUS respectively. The FEA results were good agreement with the testing results. The investigation of models with a hole indicates that the appearance time of ultimate compressive load is earlier than that of fiber breakage expanding to boundary. Moreover, the diameter and the depth of blind hole significantly influence the ultimate compressive load.

Reconfiguration and Unified Kinematics Analysis of a Metamorphic Parallel Mechanism With Bifurcated Motion

2012 ◽  
Author(s):  
Dongming Gan ◽  
Jian S. Dai ◽  
Lakmal D. Seneviratne
Keyword(s):  
Parallel Mechanism ◽  
Geometric Condition ◽  
Translation Vector ◽  
Kinematics Analysis ◽  
Constraint Equations ◽  
Mechanism Modeling ◽  
The Difference ◽  
Two Phases ◽  
Set Up ◽  
Joint Center

This paper introduced a new metamorphic parallel mechanism consisting of four reconfigurable rTPS limbs. Based on the reconfigurability of the reconfigurable Hooke (rT) joint, the rTPS limb has two phases while in one phase the limb has no constraint to the platform, in the other it constrains the spherical joint center to lie on a plane. This results in the mechanism to have ability of reconfiguration between different topologies with variable mobility. Geometric constraint equations of the platform rotation matrix and translation vector are set up based on the point-plane constraint, which reveals the bifurcated motion property in the topology with mobility 2 and the geometric condition with mobility change in altering to other mechanism topologies. Following this, a unified kinematics limb modeling is proposed considering the difference between the two phases of the reconfigurable rTPS limb. This is further applied for the mechanism modeling and both the inverse and forward kinematics is analytically solved by combining phases of the four limbs covering all the mechanism topologies.

scholarly journals Influence of Frequency on the Resolution of Magnetostrictive Bio-Inspired Whisker Sensors

2018 ◽  
Vol 2018 ◽  
pp. 1-7
Author(s):  
Ran Zhao ◽  
Bo-wen Wang ◽  
Quan-guo Lu ◽  
Jian-wu Yan ◽  
Xiao-cui Yuan
Keyword(s):  
Vibration Frequency ◽  
Dynamic Testing ◽  
Theoretical Calculations ◽  
Beam Theory ◽  
Experimental System ◽  
Flow Sensors ◽  
Maximum Resolution ◽  
Sensing Model ◽  
Euler Bernoulli Beam ◽  
Good Agreement

Magnetostrictive biomimetic whiskers have been used as tactile and flow sensors. Compared to other types of whiskers, such whiskers have the advantage of being able to perform static and dynamic measurements. For dynamic measurement, the whisker’s resolution changes with varying vibration frequency; however, the mechanism for this influence has not been studied yet. Thus, the aim of this study is to investigate the resolution–frequency correlation. First, the structure and operation principle of the whisker were analyzed. Then, the Euler–Bernoulli beam theory was employed to establish the sensing model of the magnetostrictive whisker. Finally, the mapping relationship between sensor resolution and frequency was obtained. The eigenfrequency analysis was implemented by FEM to obtain the frequency response of the whisker. A vibration experimental system was built for dynamic testing. The experimental results were in good agreement with the theoretical calculations. Furthermore, it was noted that the resolution was positively correlated with frequency, and the maximum resolution was attained at the natural frequency (two peak values appeared at the first-order and second-order eigenfrequencies). Our research reveals the manner in which a whisker sensor’s resolution is affected by the vibration frequency. The theoretical model can be used to predict the resolution of magnetostrictive whisker sensors.

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