Performance Optimization of Trapezium Rib Parameters Using Response Surface Methodology

2017 ◽  
Author(s):  
Naveen Sharma ◽  
Vaibhav Sharma ◽  
Andallib Tariq
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Hydraulic Diameter ◽  
Quadratic Model ◽  
Design Parameters ◽  
Geometrical Parameters ◽  
Performance Parameters ◽  
Rectangular Duct ◽  
Height Ratio ◽  
Experimental Values

In the present work, transient liquid crystal thermography (LCT) has been used for capturing the temperature field as well as the local heat transfer distribution inside a rectangular duct. Experiments have been carried out in an open loop airflow system at a Reynolds number (based on the channel hydraulic diameter) of 58850 and for rib height to channel hydraulic diameter ratio of 0.125. This investigation emphases headed for assessing the potential impact of design parameters such as chamfering angle and rib pitch to height ratio of the trapezium ribbed rectangular duct on the thermo-hydraulic performances, which forms the basis of analysis while using response surface methodology (RSM). The chamfering angle has been varied from 0 to 20° in a step of 5°, while the rib pitch to height ratio is varied from 8 to 12 in a step of 2. The quadratic model generated by RSM is used to predict the optimal performance parameters. The results show that different geometrical parameters have to be considered simultaneously in order to improve the performance of ribbed-duct. Eventually, based on this analysis, the optimum levels of design parameters for trapezium rib corresponding to the highest augmentation Nusselt number, the lowest friction factor, and the highest thermo-hydraulic performance have been determined. Finally, the desired correlations for all performance parameters have been developed using RSM. The comparison of predicted values with the experimental values has been carried out, which is found to be in harmony with the experimental values in the uncertainty range of ±5%., which are found to predict the performance parameters with reasonably good accuracy.

Aerothermal Characteristics of Surface-Mounted Round-Edged Slit Ribs with Performance Optimization using Response Surface Methodology

2021 ◽  
pp. 1-46
Author(s):  
Vaibhav Sharma ◽  
Andallib Tariq
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Response Surface Methodology ◽  
Nusselt Number ◽  
Response Surface ◽  
Performance Optimization ◽  
Design Parameters ◽  
Geometrical Parameters ◽  
Performance Parameters ◽  
The Impact

Abstract The author has investigated the aerothermal characteristics of round-edged ribs with a continuous slit. The experiments have been performed by mounting an array of ribs on the bottom wall inside a rectangular duct. Heat transfer characteristics have been measured using Liquid crystal Thermography (LCT), whereas flow characteristics have been measured using two-dimensional particle image velocimetry (2D-PIV) technique. Experiments have been performed for flow over a rib having ~20% blockage ratio and 10% open area ratio. Geometrical parameters considered for the study are slit angle (a) and rib pitch to height ratio (p/e). Experiments have been performed for three distinct rib configurations having a values, i.e., 0°, 5° and 10° with different arrangements having p/e values of 5, 10 and 15, at four Reynolds number ranges from 6200-12200. The heat transfer results are evaluated by examining the surface and span wise-averaged distribution of augmented Nusselt Number. Flow field results are explained within the inter rib region by examining the time-averaged normalized velocity fields, streamlines, fluctuation statistics and vorticity distribution. Further, the impact of geometrical design parameters (a and p/e) on different performance parameters, i.e., overall averaged augmented Nusselt Number, Friction Factor Ratio and Thermal Performance Factor have been analyzed at all four Reynolds number using Response Surface Methodology (RSM). Finally, the desired correlations for the performance parameters have been documented, and found in accord with an uncertainty range of ±10%.

Optimization of phenolics and antioxidants extraction from Centaurium erythraea using response surface methodology

2021 ◽  
pp. 6455-6462
Author(s):  
Wissam Zam ◽  
Ali Ali ◽  
Dimah Saleem ◽  
Sahar Alali
Keyword(s):  
Antioxidant Activity ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Volume Fraction ◽  
Quadratic Model ◽  
Natural Food ◽  
Solvent Ratio ◽  
Research Attention ◽  
Experimental Values ◽  
Centaurium Erythraea

In recent years, Centaurium erythraea extracts have attracted much research attention in the context of prevention or treatment of many diseases due to its bioactive compounds content and antioxidant activity. The antioxidants of C. erythraea are very effective as they possess excellent antioxidant activity. Thus, it can be used as a safe and natural food preservative. The aim of this study is to make extracts more effective by optimizing the extraction conditions of the phenolics and antioxidants from C. erythraea using response surface methodology (RSM) based on a central composite design (CCD). Two process variables (Methanol volume fraction and solid - solvent ratio) were evaluated at five levels (13 experimental designs). Multiple regression analyses were performed to obtain quadratic polynomial equations using RSM; each response was fitted by a quadratic model. The adequacy of the models was proven using the analysis of variance (ANOVA). The significant effects of the factors and their interactions on the extraction efficiency were investigated at 95% confidence interval. RSM indicated that the optimal extraction conditions were 71% methanol volume fraction and 2.2:10 solid:solvent ratio. Predicted values thus obtained were close to the experimental values indicating suitability of the model.

scholarly journals Effect of nutrient sources on bench scale vinegar production using response surface methodology

2005 ◽  
Vol 9 (1) ◽  
pp. 73-77 ◽  
Author(s):  
Joelma M. Ferreira ◽  
Ramdayal Swarnakar ◽  
Flávio L. H. da Silva
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Nitrogen Sources ◽  
Quadratic Model ◽  
Small Scale ◽  
Nutrient Sources ◽  
Bench Scale ◽  
Model Equations ◽  
Experimental Values ◽  
Star Configuration

The present work aims to evaluate on a bench scale, the effects of nitrogen and phosphorous nutrient source concentrations in vinegar production, a process that is used by small scale industries in the State of Paraiba. The response surface methodology has been utilized for modeling and optimization of the fermentation process. Initially a 2³ complete factorial design was used, where the effects of initial concentrations of ethyl alcohol, phosphorous and nitrogen sources were observed. After this analysis the concentration range of the nutrient variables were extended and a two level plus a star configuration factorial experimental design was performed. The experimental values are well represented by the linear and quadratic model equations obtained. The optimum concentration of ethanol was 4% in which the yield and the productivity of the acetic acid were maximized to the values of 70% and 0.87 g L-1 h-1 respectively, for a 24 hours fermentation period. The evaluation of the quadratic models showed that the yield of vinegar is maximized from 28.1 to 51.04% and the productivity from 0.69 to 1.29 g L-1 h-1 when the concentration of the nitrogen nutrient in the medium is increased from 0.2 to 2.3 g mL-1. Thus, at the optimized nitrogen nutrient concentration both the yield and the productivity of the vinegar are increased by 1.85 times.

Application of Response Surface Methodology and Central Composite Rotatable Design for Modeling and Optimization of Catalyst Compositions in Ethanol Synthesis via CO Hydrogenation

2014 ◽  
Vol 12 (1) ◽  
pp. 245-255
Author(s):  
Fang Li ◽  
Hongfang Ma ◽  
Weiyong Ying
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Co Hydrogenation ◽  
Quadratic Model ◽  
Central Composite Rotatable Design ◽  
Co Conversion ◽  
Experimental Values ◽  
Central Composite ◽  
Ethanol Synthesis ◽  
Rotatable Design

Abstract A statistical analysis about the effect of catalyst compositions on ethanol synthesis from CO hydrogenation was studied. The effect of Rh loading (0–3 wt.%), Fe loading (2–10 wt.%) and Mn loading (0.5–2.5 wt.%) of RhMnFe/γ-Al2O3 was studied through response surface methodology (RSM) combined with a central composite rotatable design (CCRD). A linear and a quadratic model were proposed to correlate the three variables to the two responses: CO conversion and ethanol selectivity. The predicted values for ethanol selectivity were in a good agreement with the experimental values, with R2 of 0.9779. The optimum conditions for achieving the maximum ethanol selectivity (27.8%) while limiting CO conversion at a moderate level (>20%) were as follows: Rh loading of 2.5 wt.%, Mn loading of 2.5 wt.% and Fe loading of 4 wt.%. Two representing catalysts were characterized by XRD, TPR and DRIFTS.

EXTRACTION OPTIMIZATION AND ANTIOXIDANT ACTIVITY OF PHENOLIC COMPOUNDS FROM AVOCADO PEEL

2019 ◽  
pp. 49-59
Author(s):  
Nu Linh Giang Ton ◽  
Thi Hoai Nguyen ◽  
Quoc Hung Vo
Keyword(s):  
Antioxidant Activity ◽  
Response Surface Methodology ◽  
Antioxidant Capacity ◽  
Response Surface ◽  
Total Antioxidant Capacity ◽  
Total Phenolic Content ◽  
Phenolic Content ◽  
Quadratic Model ◽  
Total Phenolic ◽  
Total Antioxidant

Avocado peel has been considered as a potential source of natural antioxidants in which phenolics are among the most important compounds. Therefore, this study aims to optimize the extraction process of phenolics using response surface methodology and evaluate the corresponding antioxidant activity. From the quadratic model, the optimal condition was determined including the ethanol concentration 54.55% (v/v), the solvent/solute ratio 71.82/1 (mL/g), temperature 53.03 oC and extraction time 99.09 min. The total phenolic content and the total antioxidant capacity at this condition with minor modifications were 26,74 ± 0,04 (mg GAE/g DW) and 188.06 ± 1.41 (mg AAE/g DW), respectively. The significant correlation between total phenolic content and total antioxidant capacity was also confirmed. Key words: response surface methodology, central composite rotatable design, total phenolic content, total antioxidant capacity, avocado peel

Optimisation of the Oil Extraction from Nigella sativa Seeds Using Response Surface Methodology

2017 ◽  
Vol 68 (2) ◽  
pp. 331-336
Author(s):  
Gabriela Isopencu ◽  
Mirela Marfa ◽  
Iuliana Jipa ◽  
Marta Stroescu ◽  
Anicuta Stoica Guzun ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Nigella Sativa ◽  
Polynomial Equation ◽  
Herbaceous Plant ◽  
Box Behnken Design ◽  
Pareto Analysis ◽  
Black Cumin ◽  
Mediterranean Countries ◽  
Experimental Values

Nigella sativa, also known as black cumin, an annual herbaceous plant growing especially in Mediterranean countries, has recently gained considerable interest not only for its use as spice and condiment but also for its healthy properties of the fixed and essential oil and its potential as a biofuel. Nigella sativa seeds fixed oil, due to its high content in linoleic acid followed by oleic and palmitic acid, could be beneficial to human health. The objective of this study is to determine the optimum conditions for the solvent extraction of Nigella sativa seeds fixed oil using a three-level, three-factor Box-Behnken design (BBD) under response surface methodology (RSM). The obtained experimental data, fitted by a second-order polynomial equation were analysed by Pareto analysis of variance (ANOVA). From a total of 10 coefficients of the statistical model only 5 are important. The obtained experimental values agreed with the predicted ones.

scholarly journals Optimization of Lignin Extraction Variables by Response Surface Methodology from Pine Saw Dust, and Quantification of Major Structural Units in Isolated Lignin Fraction

2021 ◽  
Vol 11 (4) ◽  
pp. 1739
Author(s):  
Muhammad Ajaz Ahmed ◽  
Jae Hoon Lee ◽  
Joon Weon Choi
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Quantum Coherence ◽  
Resonance Spectrum ◽  
Quadratic Model ◽  
Molecular Weights ◽  
Solids Loading ◽  
A Value ◽  
Lignin Extraction ◽  
Lignin Fraction

A synergistic combination of dioxane, acetic acid, and HCl was investigated for lignin extraction from pine wood biomass. After initial screening of reagent combination, response surface methodology (RSM) was used to optimize the lignin yield with respect to the variables of time 24–72 h, solids loading 5–15%, and catalyst dose 5–15 mL. A quadratic model predicted 8.33% of the lignin yield, and it was further confirmed experimentally and through the analysis of variance (ANOVA). Lignin at optimum combination exhibited features in terms of derivatization followed by reductive cleavage (DFRC) with a value of (305 µmol/gm), average molecular weights of 4358 and polydispersity of 1.65, and 2D heteronuclear single quantum coherence nuclear magnetic resonance spectrum (2D-HSQC NMR) analysis showing relative β-O-4 linkages (37.80%). From here it can be suggested that this fractionation can be one option for high quality lignin extraction from lignocellulosic biomass.

scholarly journals Optimizing Adsorption of 17α-Ethinylestradiol from Water by Magnetic MXene Using Response Surface Methodology and Adsorption Kinetics, Isotherm, and Thermodynamics Studies

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3150
Author(s):  
Mengwei Xu ◽  
Chao Huang ◽  
Jing Lu ◽  
Zihan Wu ◽  
Xianxin Zhu ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Quadratic Model ◽  
Adsorption Efficiency ◽  
Process Variables ◽  
Adsorption Time ◽  
Initial Concentration ◽  
Independent Variables ◽  
The Impact ◽  
Adsorbent Dose

Magnetic MXene composite Fe3O4@Ti3C2 was successfully prepared and employed as 17α-ethinylestradiol (EE2) adsorbent from water solution. The response surface methodology was employed to investigate the interactive effects of adsorption parameters (adsorption time, pH of the solution, initial concentration, and the adsorbent dose) and optimize these parameters for obtaining maximum adsorption efficiency of EE2. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. Optimization of the process variables for maximum adsorption of EE2 by Fe3O4@Ti3C2 was performed using the quadratic model. The model predicted maximum adsorption of 97.08% under the optimum conditions of the independent variables (adsorption time 6.7 h, pH of the solution 6.4, initial EE2 concentration 0.98 mg L−1, and the adsorbent dose 88.9 mg L−1) was very close to the experimental value (95.34%). pH showed the highest level of significance with the percent contribution (63.86%) as compared to other factors. The interactive influences of pH and initial concentration on EE2 adsorption efficiency were significant (p < 0.05). The goodness of fit of the model was checked by the coefficient of determination (R2) between the experimental and predicted values of the response variable. The response surface methodology successfully reflects the impact of various factors and optimized the process variables for EE2 adsorption. The kinetic adsorption data for EE2 fitted well with a pseudo-second-order model, while the equilibrium data followed Langmuir isotherms. Thermodynamic analysis indicated that the adsorption was a spontaneous and endothermic process. Therefore, Fe3O4@Ti3C2 composite present the outstanding capacity to be employed in the remediation of EE2 contaminated wastewaters.

scholarly journals Rheological properties of emulsions stabilized by green banana (Musa cavendishii) pulp fitted by power law model

2009 ◽  
Vol 52 (6) ◽  
pp. 1541-1553 ◽  
Author(s):  
Dayane Rosalyn Izidoro ◽  
Agnes de Paula Scheer ◽  
Maria-Rita Sierakowsk
Keyword(s):  
Response Surface Methodology ◽  
Rheological Properties ◽  
Response Surface ◽  
Power Law ◽  
Cone Angle ◽  
Rheological Behaviour ◽  
Quadratic Model ◽  
Soy Oil ◽  
Power Law Model ◽  
Green Banana

In this work, the rheological behaviour of emulsions (mayonnaises) stabilized by green banana pulp using the response surface methodology was studied. In addition, the emulsions stability was investigated. Five formulations were developed, according to design for constrained surfaces and mixtures, with the proportion, respectively: water/soy oil/green banana pulp: F1 (0.10/0.20/0.70), F2 (0.20/0.20/0.60), F3 (0.10/0.25/0.65), F4 (0.20/0.25/0.55) and F5 (0.15/0.225/0.625) .Emulsions rheological properties were performed with a rotational Haake Rheostress 600 rheometer and a cone and plate geometry sensor (60-mm diameter, 2º cone angle), using a gap distance of 1mm. The emulsions showed pseudoplastic behaviour and were adequately described by the Power Law model. The rheological responses were influenced by the difference in green banana pulp proportions and also by the temperatures (10 and 25ºC). The formulations with high pulp content (F1 and F3) presented higher shear stress and apparent viscosity. Response surface methodology, described by the quadratic model,showed that the consistency coefficient (K) increased with the interaction between green banana pulp and soy oil concentration and the water fraction contributed to the flow behaviour index increase for all emulsions samples. Analysis of variance showed that the second-order model had not significant lack-of-fit and a significant F-value, indicating that quadratic model fitted well into the experimental data. The emulsions that presented better stability were the formulations F4 (0.20/0.25/0.55) and F5 (0.15/0.225/0.625).

scholarly journals Optimizing Physiochemical and Sensory Properties of Infrared-Hot Air Roasted Sunflower Kernels Using Response Surface Methodology

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Mahdis Mosayebi ◽  
Mahdi Kashaninejad ◽  
Leila Najafian
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Color Change ◽  
Specific Energy Consumption ◽  
Chemical Properties ◽  
Sensory Properties ◽  
Quadratic Model ◽  
Total Phenolic ◽  
Phenolic Contents ◽  
Hot Air

Roasting sunflower kernels is a key process in production of nuts. In this study, the effect of roasting conditions, including hot air temperature (120–160°C), infrared (IR) power (400–600 W) and roasting time (3–10 min) on energy and specific energy consumption, color parameters (L∗, a∗, b∗, ΔE, BI, SI, WI, and h°), texture, moisture content, chemical properties (pH and total phenolic contents, peroxide value (PV), and sensory properties of sunflower kernel were investigated. In addition, the best models for the responses were obtained, and the proper roasting conditions were determined using response surface methodology (RSM). A quadratic model was proposed for color change (L∗, ΔE, SI, and WI), moisture and total phenol contents, linear relation for a∗, b∗, h°, and 2FI for BI, texture, PV, and pH. Roasting at 425.7 W IR power and 124.3°C for 3.7 min was found to be convenient or proper roasting conditions.

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