Transesterification of used cooking oil at ambient temperature using novel solvent: Experimental investigations and optimisation by response surface methodology

Chatter is detrimental to turning operations and leads to inferior surface topography, reduced productivity, dimensional accuracy, and shortened tool life. Avoidance of chatter has mostly been through reliance on heuristics such as: limiting material removal rates or selecting low spindle speeds and shallow depth of cuts. But, modern industries demand increased output and not steady operational limits. Various research efforts have therefore focused on developing mathematical models for chatter formation. However, as yet there is no existent model that meets all experimental verification. This research employed a novel technique based on the synergy of statistical modeling and experimental investigations in order to develop an effective empirical mathematical model for chatter amplitude and to subsequently find optimal machining conditions. Ti-6Al-4V, Titanium alloy, was used as the work-piece due to its increased popularity in applications related to aerospace, automotive, nuclear, medical, marine etc. A sequence of 15 experimental runs was conducted based on a small Central Composite Design (CCD) model in Response Surface Methodology (RSM). The primary (independent) parameters were: cutting speed, feed, and depth of cut. The tool overhang was kept constant at 70 mm. An engine lathe (Harrison M390) was employed for turning purposes. The data acquisition system comprised a vibration sensor (accelerometer) and a signal conditioning unit. The resultant vibrations were analyzed using the DASYLab 5.6 software. The best model was found to be quadratic which had a confidence level of 95% (ANOVA) and insignificant Lack of Fit (LOF) in Fit and Summary analyses. Desirability Function (DF) approach predicted minimum vibration amplitude of 0.0276 Volts and overlay plots identified two preferred machining regimes for optimal vibration amplitude.

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A fast and accurate solution to optimal design of eddy-current PMCs with standard disc type

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-210094 ◽

2021 ◽

pp. 1-19

Author(s):

Zheng rong Xia ◽

Yong chen Pei ◽

Dong xu Wang ◽

Shun Wang

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Optimal Solution ◽

Industrial Applications ◽

Accurate Solution ◽

Parameter Determination ◽

Experimental Investigations ◽

Fe Model ◽

Contribution Rate ◽

Standard Disc

Although permanent magnet couplings (PMCs) have been under research for many years and have found successful industrial applications, this is still a technology under development. Accurate parameter determination is of significance for performance analysis and critical decisions on PMC design. However, the determination can often lead to an unacceptable increase in computation, especially when finite elements (FE) are used. The study aims to develop an FE model that is used for the structural design of a standard-disc type PMC for optimal torque. For the quick and accurate design, an integration optimal solution of the response surface methodology (RSM) and the Taguchi’s method was proposed. To verify the simulation, a series of experimental investigations were conducted on a self-developed testing platform. Furthermore, for a minimum set of FE analyses (FEA), a quantitative indicator called contribution rate, which can reflect effect level of structure parameters on the torque, was given based on the Taguchi method. Apart from this, the orthogonal matrix was used for the reduction of the FE calculation. Based on the contribution rate, the response surface methodology was adopted for the optimal torque determination with no increase in the PM volume. According to the optimization results, a fitting formula, which considers the contribution rates of the optimization variables, was presented. The results suggest that the FE simulations agree very well with the experiments, and the fitting formula can be used in the PMC design.

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The Optimization of Ozonolysis Reaction For Synthesis of Biopolyol From Used Palm Cooking Oil

ASEAN Journal of Chemical Engineering ◽

10.22146/ajche.49711 ◽

2014 ◽

Vol 14 (1) ◽

pp. 1

Author(s):

Edy Purwanto ◽

Lieke Riadi ◽

Nathania Tamara I. ◽

Mellisha Ika K.

Keyword(s):

Reaction Time ◽

Response Surface ◽

Ozone Concentration ◽

Molar Ratio ◽

Optimal Operating ◽

Optimal Operating Condition ◽

Hydroxyl Value ◽

Independent Variables ◽

Cooking Oil ◽

Used Cooking Oil

Biopolyol is a raw material for synthesis of polyurethanes which is used as thermoset and thermoplastic materials, adhesives, rigid or non-rigid foams and also for coating. The utilization of waste edible oil as feedstock for synthesis of biopolyol has attracted some researchers. However, there is little attention focused on the application of ozone technology for synthesis of biopolyol from used cooking oil through ozonolysis reaction. Response surface methodology was performed to determine the optimal operating condition in the synthesis of biopolyol using ozone and sorbitol as a hydroxyl group source. The influence of input variables such as temperature, reaction time, molar ratio of oil to sorbitol and ozone concentration on hydroxyl value quantified was studied. The optimal condition was determined by high amount of hydroxyl value resulted from response surface method which used the experimental data. The ozonolysis reaction was conducted in a batch reactor equipped with agitator, tube sparger, thermocouple, reflux condenser and potassium iodide trap. Central composite design with four independent variables and one response variable was performed to determine the influence of independent variables on output variable of hydroxyl value of biopolyol. The hydroxyl value of polyol is a quadratic function of molar ratio of oil to methanol and a linear function of reaction temperature. The optimal operating condition was achieved at a temperature of 25℃, a reaction time of 5 hours, molar ratio of used cooking oil to sorbitol is 1:7 and ozone concentration about 4.8%.Keywords: Ozonolysis; Biopolyol; Hydroxyl value; Used cooking oil; Palm oil

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Effects of Euler Angles of Vertical Cambered Otter Board on Hydrodynamics Based on Response Surface Methodology and MOGA

Volume 9: Rodney Eatock Taylor Honoring Symposium on Marine and Offshore Hydrodynamics; Takeshi Kinoshita Honoring Symposium on Offshore Technology ◽

10.1115/omae2019-95308 ◽

2019 ◽

Author(s):

Gang Wang ◽

Rong Wan ◽

Liuyi Huang ◽

Fenfang Zhao ◽

Xinxin Wang ◽

...

Keyword(s):

Numerical Simulation ◽

Response Surface Methodology ◽

Response Surface ◽

Center Of Pressure ◽

Lift Coefficient ◽

Hydrodynamic Characteristics ◽

Experimental Investigations ◽

Euler Angles ◽

Multi Objective Genetic Algorithm ◽

Working Posture

Abstract In this present work, effects of three Euler angles (Angle of Attack (AOA), Angle of Trim (AOT), Angle of Pitch (AOP)) of vertical cambered otter board on hydrodynamic characteristics (drag coefficient (Cd), lift coefficient (Cl), center-of-pressure coefficients (Cp)) were studied based on numerical simulation combined with Kriging Response Surface Methodology (KRSM) and Multi-Objective Genetic Algorithm (MOGA). Wind tunnel experiments were carried out to validate the accuracy of response surface based on numerical simulation. It was demonstrated that AOA had prominent effects on Cd and Cl, while AOT and AOP had less effects. The working posture of otter board were recommended to lean inwards (0°∼6°) and forward (−10°∼0°) to improve the lift-drag ratio without sacrificing Cl. The influences of AOT and AOP on positions of center-of-pressure point were less significant than that of AOA and decreasing with the increase of AOA. In addition, response surface of hydrodynamic coefficients around the critical AOA was a decent indicator of occurrence of stall. Finally, three candidate cases were selected to satisfy the high working efficiency by MOGA, which was consistent with the above recommendations. This study provided a scientific reference of response surface experimental investigations methodology and the configuration of Euler angles of otter board.

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