scholarly journals Energy and Efficiency Evaluation of Feedback Branch Design in Thermoacoustic Stirling-Like Engines

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3867 ◽  
Author(s):  
Iniesta ◽  
Olazagoitia ◽  
Vinolas ◽  
Gros
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
High Reliability ◽  
Reduction Process ◽  
Acoustic Power ◽  
Great Difficulty ◽  
Design Parameters ◽  
Internal Diameter ◽  
Design Variables ◽  
External Combustion

Stirling-like thermoacoustic generators are external combustion engines that provide useful acoustic power in the absence of moving parts with high reliability and respect for the environment. The study of these systems involves a great complexity since the parameters that describe them, besides being numerous, present a high degree of coupling between them. This implies a great difficulty in characterizing the effects of any parametric variation on the performance of these devices. Due to the huge amount of data to analyze, the experiments and simulations required to address the problem involve high investments in time and resources, sometimes unaffordable. This article presents, how a sensitivity analysis applying the response surface methodology can be applied to optimize the feedback branch of a thermoacoustic Stirling-like engine. The proposed study is made by evaluating the comparative relevance of seven design variables. The dimensional reduction process identifies three significant factors: the frequency of operation, the internal diameter of compliance, and the inertance. Subsequently, the Response Surface Methodology is applied to assess the interaction effects of these three design parameters on the efficiency of the thermoacoustic engine, and an improvement of 6% has been achieved. The enhanced values given by the response surface methodology are validated using the DeltaEC software.

scholarly journals Optimization of Eugenol Extraction from Clove Oil using Response Surface Methodology

2015 ◽  
Vol 9 (11) ◽  
pp. 68
Author(s):  
Widayat Widayat ◽  
Hadiyanto Hadiyanto ◽  
Bambang Cahyono ◽  
Ngadiwiyana Ngadiwiyana
Keyword(s):  
Response Surface Methodology ◽  
Optimum Condition ◽  
Central Composite Design ◽  
Response Surface ◽  
Design Method ◽  
Main Process ◽  
Clove Oil ◽  
Design Variables ◽  
Central Composite

The objective of this research was to obtain optimum condition of eugenol production from clove oil using a central composite design method. The main process occured in the eugenol production was saphonification and neutralization processes. In order to optimize these processes, the ratio of NaOH/clove oil and temperature were studied as design variables i.e. ratio of NaOH/clove oil=1:2.5-1:3.5 while temperature was varied between 40 and 60oC. The yield of eugenol was considered as the main response in of this experiment. The result showed that the optimum condition was achieved when the temperature and the ratio of NaOH/clove oil were 50oC and 2.75:1, respectively and the yield was 39.17%.<br />

Dry Sliding Wear Behaviour of Magnesium nanocomposites using Response Surface Methodology

2021 ◽  
pp. 1-18
Author(s):  
Kartheesan S ◽  
B. Shahul hamid Khan ◽  
M Kamaraj ◽  
Manoj Gupta ◽  
Sravya Tekumalla
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Sliding Wear ◽  
Wear Behaviour ◽  
Design Parameters ◽  
Dry Sliding Wear ◽  
Wear Loss ◽  
Sliding Velocity ◽  
Sliding Distance ◽  
Sliding Wear Behaviour

Abstract In this study, a pure magnesium material reinforced with 0.5, 1, 1.5, and 2 weight % of CaO was prepared through disintegrated melt deposition technique. Nanocomposites were investigated for their sliding wear behaviour in dry condition at room temperature. Amount of CaO, Load, sliding distance, and Sliding velocity were selected as input design parameters at their five-level in central composite design using Minitab 18.1 statistical software. The influence of design parameters on wear loss is reported through the Response Surface Methodology (RSM). ANOVA was used to confirm the soundness of the developed regression equation. The results indicate the contribution of linear, quadratic, and interaction terms of design parameters on response. 3D response surface and 2D contour plots are indicated the interaction effect. The result shows that an increase in sliding velocity contributes to a decrease in the wear loss of the composites because of the emergence of protective oxidative layer at the surfaces of the pins, which is confirmed through FESEM and EDAX analysis of the pin surfaces. Wear loss of the material decreased as amount of CaO increased. The ANOVA analysis concluded that the sliding distance and load contribute significantly to wear loss of the composites and their percentage of contribution is 64.02 % and 3.69%.

Degradation of Paracetamol by Fenton-Like Process in Conjunction with Sonication

2015 ◽  
Vol 737 ◽  
pp. 321-324
Author(s):  
Rong Yao Wang ◽  
Xi Kui Wang
Keyword(s):  
Response Surface Methodology ◽  
Synergistic Effect ◽  
Response Surface ◽  
Acoustic Power ◽  
Ultrasonic Cavitation ◽  
Sponge Iron ◽  
Optimum Conditions ◽  
Initial Ph

The degradation of the pharmaceutical paracetamol by using Fenton-like process in conjunction with ultrasonic cavitation was investigated. An evident synergistic effect was found in the combination of sonication and Fenton-like process. Through the application of Response Surface Methodology optimization, the optimum conditions for the degradation of paracetamol were initial pH 3.0, H2O27.0 mmol·L-1and sponge iron 4 g·L-1with acoustic power of 200 W. Under these parameters could obtain 99% degradation of 100mg·L-1paracetamol solution within 30 min treatment.

Design Study of Dovetail Geometries of Turbine Blades Using Abaqus and Isight

2012 ◽  
Author(s):  
Youngwon Hahn ◽  
John I. Cofer
Keyword(s):  
Surrogate Model ◽  
High Reliability ◽  
Turbine Blades ◽  
Optimization Methods ◽  
Nonlinear Static Analysis ◽  
Design Parameters ◽  
Second Step ◽  
Nsga Ii ◽  
Python Script ◽  
Design Variables

Blades in gas and steam turbines continually face more challenging requirements for high reliability and efficiency. In order to meet these challenges in an increasingly competitive marketplace, blade design engineers are always looking for more efficient ways to design the blades in the shortest possible time and at the lowest possible cost while meeting multiple design objectives. In this paper, several design studies are performed using Abaqus and Isight to optimize the minimum contact pressure and stress around the dovetail of a typical turbine blade in order to achieved desired goals for stress levels. First, nine design parameters describing the dimensions of the dovetail are set up in a Python script which can be executed in Abaqus/CAE. The Python script generates the entire finite element model including boundary and loading conditions in Abaqus/CAE. A nonlinear static analysis considering centrifugal loading is performed in this work. After setting up the workflow using the Python script and Abaqus/CAE, Isight is used to automate the process to achieve the optimized dimensions of the dovetail. The optimization is performed in two steps. First, a surrogate model using the Optimal Latin Hypercube approximation method is created using tools in Isight. In this step, the surrogate model is used to determine the optimum values of the design variables, as well as the sensitivity of the design to the selected design variables. It also can be observed that the design is especially sensitive to five of the design variables. In the second step of the optimization, the five design variables to which the design is most sensitive are selected for further optimization by setting the other design variables to the optimized values obtained in the first step of the optimization. In this second step, several different optimization methods supported in Isight are used, including the NSGA-II non-dominated sorting genetic algorithm, Downhill Simplex, and an evolutionary optimization algorithm. Results from these methods are compared with those obtained using other common optimization methods in Isight.

scholarly journals Application of Response Surface Methodology to Enhance Phenol Removal from Refinery Wastewater by Microwave Process

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Sherif A. Younis ◽  
Waleed I. El-Azab ◽  
Nour Sh. El-Gendy ◽  
Shuokr Qarani Aziz ◽  
Yasser M. Moustafa ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Output Power ◽  
Petroleum Refinery ◽  
Irradiation Time ◽  
Reaction Rates ◽  
Design Parameters ◽  
Phenol Removal ◽  
Refinery Wastewater ◽  
Petroleum Refinery Wastewater

Phenol contaminated petroleum refinery wastewater presents a great threat on water resources safety. This study investigates the effect of microwave irradiation on removal of different concentrations of phenol in an attempt for petroleum refinery wastewater treatment. The obtained results show that the MW output power and irradiation time have a significant positive effect on the removal efficiency of phenol. The kinetic reaction is significantly affected by initial MW output power and initial phenol concentrations. Response surface methodology (RSM) was employed to optimize and study the interaction effects of process parameters: MW output power, irradiation time, salinity, pH, and H2O2 concentration using central composite design (CCD). From the CCD design matrix, a quadratic model was considered as an ultimate model (R2 = 0.75) and its adequacy was justified through analysis of variance (ANOVA). The overall reaction rates were significantly enhanced in the combined MW/H2O2 system as proved by RSM. The optimum values for the design parameters of the MW/H2O2 process were evaluated giving predicted phenol removal percentage of 72.90% through RSM by differential approximation and were confirmed by experimental phenol removal of 75.70% in a batch experiment at optimum conditions of 439 W MW power, irradiation time of 24.22 min, salinity of 574 mg/L, pH 5.10, and initial H2O2 concentration of 10% (v/v).

Optimizing the Pomelo Oils Extraction Process by Microwave-Assisted Hydro-Distillation Using Soft Computing Approaches

2018 ◽  
Vol 279 ◽  
pp. 217-221 ◽  
Author(s):  
Tran Thien Hien ◽  
Nguyen Phu Thuong Nhan ◽  
Nguyen Duy Trinh ◽  
Van Thi Thanh Ho ◽  
Long Giang Bach
Keyword(s):  
Response Surface Methodology ◽  
Essential Oil ◽  
Response Surface ◽  
Soft Computing ◽  
Microwave Power ◽  
High Reliability ◽  
Extraction Process ◽  
Oil Extraction ◽  
Microwave Assisted ◽  
Number Of Factors

Pomelo (Citrus grandis .Linn Osbeck) oils is becoming more and more popular for everyone because it has great benefits. However, the efficiency of essential oil extraction process depends on the method and is influenced by a number of factors. Microwave-assisted hydro-distillation and Response Surface Methodology are selected for extracting and optimizing the factors affect the yield of the pomelo oil. The pomelo oil has the optimum yield was 4.5% when extracted with a water and peels ratio of 3,119: 1 (ml/g) for time extraction of 117.336 (minutes) at a microwave power of 403.115 (W) with high reliability (R2 = 0.9831)

scholarly journals Efficient Removal of Cr (VI) with Biochar and Optimized Parameters by Response Surface Methodology

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 889
Author(s):  
Hao Peng ◽  
Jing Guo ◽  
Hongzhi Qiu ◽  
Caiqiong Wang ◽  
Chenyu Zhang ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
Reaction Temperature ◽  
Reduction Process ◽  
Order Model ◽  
Reaction Conditions ◽  
Efficient Reduction ◽  
Experimental Parameters ◽  
Positive Effect

A highly efficient reduction process of Cr (VI) with biochar was conducted in this paper. The results showed that nearly 100% Cr (VI) was reduced at selected reaction conditions: Dosage of biochar at m (C)/m(Cr) = 3.0, reaction temperature of 90 °C, reaction time of60 min, and concentration of H2SO4 of 20 g/L. The reduction kinetics analysis demonstrated that the reduction of Cr (VI) fitted well with the pseudo-first-order model and the apparent activation energy was calculated to be 40.24 kJ/mol. Response surface methodology confirmed that all of the experimental parameters had a positive effect on the reduction of Cr (VI). The influence of each parameter on the reduction process followed the order: Dosage of biochar>concentration of H2SO4>reaction temperature >reaction time. This paper provides a versatile strategy for the treatment of wastewater containing Cr (VI) and shows a bright tomorrow for wastewater treatment.

scholarly journals Efficient Removal of Cr (VI) with Biochar and Parameters Optimized by Response Surface Methodology

2021 ◽  
Author(s):  
Hao Peng ◽  
Jing Guo
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
Reaction Temperature ◽  
Reduction Process ◽  
Order Model ◽  
Reaction Conditions ◽  
Efficient Reduction ◽  
Experimental Parameters ◽  
Positive Effect

A highly efficient reduction process of Cr (VI) with biochar was conducted in this paper. The results showed that nearly 100% Cr (VI) was reduced at selected reaction conditions: the dosage of biochar at m (C)/m(Cr) = 3.0, reaction temperature of 90 ℃, reaction time at 60 min and concentration of H2SO4 of 20 g/L, respectively. The reduction kinetics analysis demonstrated that the reduction of Cr (VI) fitted well with the pseudo-first-order model and the apparent activation energy was calculated to 40.24 kJ/mol. Response surface methodology confirmed that all the experimental parameters had positive effect on the reduction of Cr (VI). The influence of each parameter on the reduction process followed the order: dosage of biochar&gt; Concentration of H2SO4 &gt; Reaction Temperature &gt; Reaction Time. This paper provided a versatile strategy for treatment of wastewater containing Cr (VI) and showed a bright tomorrow for wastewater treatment.

Simulation-based search for optimal designs of accelerated life tests through response surface methodology

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Daniel Ayasse ◽  
Kangwon Seo
Keyword(s):  
Response Surface Methodology ◽  
Optimal Design ◽  
Objective Function ◽  
Response Surface ◽  
Failure Time ◽  
Simulated Data ◽  
Accelerated Life Test ◽  
Design Parameters ◽  
Content Type ◽  
Accelerated Life

PurposePlanning an accelerated life test (ALT) for a product is an important task for reliability practitioners. Traditional methods to create an optimal design of an ALT are often computationally burdensome and numerically difficult. In this paper, the authors introduce a practical method to find an optimal design of experiments for ALTs by using simulation and empirical model building.Design/methodology/approachInstead of developing the Fisher information matrix-based objective function and analytic optimization, the authors suggest “experiments for experiments” approach to create optimal planning. The authors generate simulated data to evaluate the quantity of interest, e.g. 10th percentile of failure time and apply the response surface methodology (RSM) to find an optimal solution with respect to the design parameters, e.g. test conditions and test unit allocations. The authors illustrate their approach applied to the thermal ALT with right censoring and lognormal failure time distribution.FindingsThe design found by the proposed approach shows substantially improved statistical performance in terms of the standard error of estimates of 10th percentile of failure time. In addition, the approach provides useful insights about the sensitivity of each decision variable to the objective function.Research limitations/implicationsMore comprehensive experiments might be needed to test its scalability of the method.Practical implicationsThis method is practically useful to find a reasonably efficient optimal ALT design. It can be applied to any quantities of interest and objective functions as long as those quantities can be computed from a set of simulated datasets.Originality/valueThis is a novel approach to create an optimal ALT design by using RSM and simulated data.

Sign in / Sign up

Export Citation Format

Share Document