A Case Study of Turbulent Free Jet Flows Issuing from Rectangular Slots on Process Performances and Quality of Hot-Air-Dried Apple

This study deals with the improvement in drying process performances and the quality of the final product for industrial equipment in the food industry. Designers need to optimize the design parameters of devices to create synergies between the greater energy efficiency of the process and high-quality dried products. Air impingement drying was carried out on apple cylinders at 323 K and with air velocities ranging between 30 and 60 m s−1. The studied drying process presents a particular setup of jets as they are multiple rectangular slot jets issued from triangular nozzles. The effect of four design jet parameters (slot width, nozzle-to-surface height, nozzle-to-nozzle spacing, and airflow) on the drying process performances and the quality of the final product was analyzed and optimized using response surface methodology (RSM). A minimal influence of design jet parameters on the process performances was shown, while an important impact was observed on the quality of dried apple. The slot width and the nozzle-to-nozzle spacing had a significant effect on the textural and functional properties. Predictive models were established and good agreements were found between predictive and observed values. Sorption isotherms were properly modeled by the Guggenheim–Anderson–de Boer (GAB) model.

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ON THE TRESHOLD BETWEEN VISCOUS AND INVISCID INSTABILITY ANALYSIS OF FREE JET FLOWS

10.26678/abcm.cobem2019.cob2019-1927 ◽

2019 ◽

Author(s):

Mateus Avanci ◽

davi souza ◽

Leonardo Santos de Brito Alves ◽

Rômulo Bessi Freitas

Keyword(s):

Jet Flows ◽

Instability Analysis ◽

Free Jet ◽

Inviscid Instability

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DIAGNOSING QUALITY OF FRICTION SYSTEMS OF MECHANISMS OF DEVICES

Issues of radio electronics ◽

10.21778/2218-5453-2019-7-10-13 ◽

2019 ◽

Vol 1 (7) ◽

pp. 10-13

Author(s):

D. Yu. Ershov ◽

I. N. Lukyanenko ◽

E. E. Aman

Keyword(s):

Surface Defects ◽

Diagnostic Methods ◽

Design Parameters ◽

Diagnostic Model ◽

Mechanical Assemblies ◽

Local Defects ◽

Relationship Of ◽

The Relationship ◽

Production And Operation

The article shows the need to develop diagnostic methods for monitoring the quality of lubrication systems, which makes it possible to study the dynamic processes of contacting elements of the friction systems of instrument mechanisms, taking into account roughness parameters, the presence of local surface defects of elements and the bearing capacity of a lubricant. In the present article, a modern diagnostic model has been developed to control the quality of the processes of production and operation of friction systems of instrument assemblies. With the help of the developed model, it becomes possible to establish the relationship of diagnostic and design parameters of the mechanical system, as well as the appearance of possible local defects and lubricant state, which characterize the quality of friction systems used in many mechanical assemblies of the mechanisms of devices. The research results are shown in the form of nomograms to assess the defects of the elements of friction mechanisms of the mechanisms of the devices.

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Research on the Optimal Design Method of the Main Components for the Wheelchair Pickup

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.791-793.799 ◽

2013 ◽

Vol 791-793 ◽

pp. 799-802

Author(s):

Ya Ping Wang ◽

H.R. Shi ◽

L. Gao ◽

Z. Wang ◽

X.Y. Jia ◽

...

Keyword(s):

Parametric Design ◽

Design Method ◽

Basic Function ◽

Design Parameters ◽

Algorithm Optimization ◽

Optimization Analysis ◽

Research Designs ◽

Optimal Design Method ◽

Main Components

With the increasing of the aging of population all over the world, and With the inconvenience coming from diseases and damage, there will be more and more people using the wheelchair as a tool for transport. When it cant be short of the wheelchair in the daily life, the addition of the function will bring the elevation of the quality of life for the unfortunate. Staring with this purpose, the research designs a pickup with planetary bevel gear for the wheelchair. After determining the basic function of the wheelchair aids, the study determines the design parameters by using the knowledge of parametric design and completes the model for the system with Pro/E, on the other hand, it completes key components optimization analysis which is based on genetic algorithm optimization.

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Research on the Reliability of Box for Gear Test Bed

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.121-126.1744 ◽

2011 ◽

Vol 121-126 ◽

pp. 1744-1748

Author(s):

Xiang Yang Jin ◽

Tie Feng Zhang ◽

Li Li Zhao ◽

He Teng Wang ◽

Xiang Yi Guan

Keyword(s):

Power Flow ◽

Dynamic Performance ◽

Three Dimensional ◽

Design Parameters ◽

The Finite Element Method ◽

Test Bed ◽

Kinematics Simulation ◽

Beveloid Gears ◽

Overall Performance

To determine the efficiency, load-bearing capacity and fatigue life of beveloid gears with intersecting axes, we design a mechanical gear test bed with closed power flow. To test the quality of its structure and predict its overall performance, we establish a three-dimensional solid model for various components based on the design parameters and adopt the technology of virtual prototyping simulation to conduct kinematics simulation on it. Then observe and verify the interactive kinematic situation of each component. Moreover, the finite element method is also utilized to carry out structural mechanics and dynamics analysis on some key components. The results indicate that the test bed can achieve the desired functionality, and the static and dynamic performance of some key components can also satisfy us.

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Freeze-drying microscopy in mathematical modeling of a biomaterial freeze-drying

Brazilian Journal of Pharmaceutical Sciences ◽

10.1590/s1984-82502012000200003 ◽

2012 ◽

Vol 48 (2) ◽

pp. 203-209 ◽

Cited By ~ 3

Author(s):

Camila Figueiredo Borgognoni ◽

Joyce da Silva Bevilacqua ◽

Ronaldo Nogueira de Moraes Pitombo

Keyword(s):

Mathematical Modeling ◽

Freeze Drying ◽

Drying Process ◽

Critical Temperatures ◽

Fundamental Properties ◽

Moving Interface ◽

Energy Consuming ◽

Sublimation Rates ◽

Time And Energy

Transplantation brings hope for many patients. A multidisciplinary approach on this field aims at creating biologically functional tissues to be used as implants and prostheses. The freeze-drying process allows the fundamental properties of these materials to be preserved, making future manipulation and storage easier. Optimizing a freeze-drying cycle is of great importance since it aims at reducing process costs while increasing product quality of this time-and-energy-consuming process. Mathematical modeling comes as a tool to help a better understanding of the process variables behavior and consequently it helps optimization studies. Freeze-drying microscopy is a technique usually applied to determine critical temperatures of liquid formulations. It has been used in this work to determine the sublimation rates of a biological tissue freeze-drying. The sublimation rates were measured from the speed of the moving interface between the dried and the frozen layer under 21.33, 42.66 and 63.99 Pa. The studied variables were used in a theoretical model to simulate various temperature profiles of the freeze-drying process. Good agreement between the experimental and the simulated results was found.

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Design on Parameterized Drafting System of Centrifugal Fan

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.34-35.192 ◽

2010 ◽

Vol 34-35 ◽

pp. 192-196

Author(s):

Jiang Zhu ◽

Limin Chen ◽

Ping Yuan Xi

Keyword(s):

Aerodynamic Force ◽

Geometric Parameters ◽

Rapid Response ◽

Design Parameters ◽

Centrifugal Fan ◽

Aerodynamic Design ◽

Key Factors ◽

Fan Speed ◽

Force Calculation

The impeller is the important pneumatic part of centrifugal fan, and its structure performances are key factors which affect the whole performances of fan. The CAD module of centrifugal fan can realize the automation of aerodynamic force calculation. According to demands, computer can automatically complete aerodynamic force calculation and further determine major geometric parameters of impeller of fan. Speed coefficient and diametral quotient are two important parameters reflecting the character of ventilating fan. The relation curve between the speed coefficient and diametral quotient of various fans is plotted in this paper. The CAD module of impeller of centrifugal fan can realize such functions as aerodynamic design and parameterization drawing of impeller, and can accomplish rapid response from receiving design parameters to profiled impeller of fan, so that it can improve the quality of drawing.

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Heat Transfer in Compartment Fires Near Regions of Ceiling-Jet Impingement on a Wall

Journal of Heat Transfer ◽

10.1115/1.3250698 ◽

1989 ◽

Vol 111 (2) ◽

pp. 455-460 ◽

Cited By ~ 7

Author(s):

L. Y. Cooper

Keyword(s):

Heat Transfer ◽

Jet Impingement ◽

Problem Formulation ◽

Jet Flows ◽

Fire Plume ◽

Compartment Fires ◽

Free Jet ◽

Wall Impingement ◽

Energy Release Rates ◽

Scale Experiment

The problem of heat transfer to walls from fire-plume-driven ceiling jets during compartment fires is introduced. Estimates are obtained for the mass, momentum, and enthalpy flux of the ceiling jet immediately upstream of the ceiling–wall junction. An analogy is drawn between the flow dynamics and heat transfer at ceiling-jet/wall impingement and at the line impingement of a wall and a two-dimensional, plane, free jet. Using the analogy, results from the literature on plane, free-jet flows and corresponding wall-stagnation heat transfer rates are recast into a ceiling-jet/wall-impingement-problem formulation. This leads to a readily usable estimate for the heat transfer from the ceiling jet as it turns downward and begins its initial descent as a negatively buoyant flow along the compartment walls. Available data from a reduced-scale experiment provide some limited verification of the heat transfer estimate. Depending on the proximity of a wall to the point of plume–ceiling impingement, the result indicates that for typical full-scale compartment fires with energy release rates in the range 200–2000 kW and fire-to-ceiling distances of 2–3 m, the rate of heat transfer to walls can be enhanced by a factor of 1.1–2.3 over the heat transfer to ceilings immediately upstream of ceiling-jet impingement.

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Deep Hole Honing Based on Squeeze Film Damping Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.76-78.252 ◽

2009 ◽

Vol 76-78 ◽

pp. 252-257

Author(s):

Tian Biao Yu ◽

Ya Dong Gong ◽

Wan Shan Wang

Keyword(s):

Differential Equation ◽

Experimental Result ◽

Squeeze Film ◽

Design Parameters ◽

Improve Quality ◽

Deep Hole ◽

Squeeze Film Damper ◽

Squeeze Film Damping ◽

Hole Machining

In order to improve quality of deep hole machining, a new method of deep hole honing based on squeeze film damping technology is put forward. For analysis effect on damper parameters on honing quality, motion differential equation of honing spindle with a squeeze film damper (SFD) is established according to D' Alembert principle and according simulations are studied. Spindle of deep hole honing with a SFD is designed based on the result of simulations and experiments are carried on. Experimental result shows that SFD with reasonable design parameters has excellent damping function to honing spindle, and it can make the vibration of honing spindle reduced 20%～30% and the quality of deep hole machining improved 10%～20%.

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A robust multi response surface approach for optimization of multistage processes

International Journal of Quality & Reliability Management ◽

10.1108/ijqrm-11-2018-0296 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Amir Moslemi ◽

Mahmood Shafiee

Keyword(s):

Robust Optimization ◽

Response Surface ◽

Numerical Study ◽

Ordinary Least Squares ◽

Response Surfaces ◽

Estimation Methods ◽

Design Parameters ◽

Optimization Approach ◽

Content Type

PurposeIn a multistage process, the final quality in the last stage not only depends on the quality of the task performed in that stage but is also dependent on the quality of the products and services in intermediate stages as well as the design parameters in each stage. One of the most efficient statistical approaches used to model the multistage problems is the response surface method (RSM). However, it is necessary to optimize each response in all stages so to achieve the best solution for the whole problem. Robust optimization can produce very accurate solutions in this case.Design/methodology/approachIn order to model a multistage problem, the RSM is often used by the researchers. A classical approach to estimate response surfaces is the ordinary least squares (OLS) method. However, this method is very sensitive to outliers. To overcome this drawback, some robust estimation methods have been presented in the literature. In optimization phase, the global criterion (GC) method is used to optimize the response surfaces estimated by the robust approach in a multistage problem.FindingsThe results of a numerical study show that our proposed robust optimization approach, considering both the sum of square error (SSE) index in model estimation and also GC index in optimization phase, will perform better than the classical full information maximum likelihood (FIML) estimation method.Originality/valueTo the best of the authors’ knowledge, there are few papers focusing on quality-oriented designs in the multistage problem by means of RSM. Development of robust approaches for the response surface estimation and also optimization of the estimated response surfaces are the main novelties in this study. The proposed approach will produce more robust and accurate solutions for multistage problems rather than classical approaches.

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