This investigation examines mathematical modelling and experimental validation of two types of solar cookers: a box type with tilted intercept area equipped with one external reflector, and a parabolic cooker with a new configuration. Experiments were carried out with the cookers filled with two kilograms of water from 08:00 to 15:00 solar time. During the experiments, temperature gain in the box-type solar cooker was recorded at about 69.8 °C and in the parabolic-type solar cooker at 73.6 °C at the stagnation point. Direct normal irradiation in three distinct study areas was observed and found that it varied from 7.6 to 10 kWh m⁻². Cooking pot placed in parabolic cooker was varied between 130 and 132 °C. Centre and south-east regions of study areas where global irradiation varied from 8 to 8.4 kWh m⁻² were found suitable for box-type solar cooker and cooking pot temperature were found in the range of 100 °C to 105 °C. Mathematical modelling was programmed in MATLAB. The theoretical results were consistent with experiential data for both types of solar cookers. The effectiveness of the two cooker types can be deduced from the maps. It is found the use of the cookers in Northern and Southern regions of the country was not identical. Their suitability for cooking depends on the amount of solar radiations received.

This investigation examines mathematical modelling and experimental validation of two types of solar cookers: a box type with tilted intercept area equipped with one external reflector, and a parabolic cooker with a new configuration. Experiments were carried out with the cookers filled with two kilograms of water from 08:00 to 15:00 solar time. During the experiments, temperature gain in the box-type solar cooker was recorded at about 69.8 °C and in the parabolic-type solar cooker at 73.6 °C at the stagnation point. Direct normal irradiation in three distinct study areas was observed and found that it varied from 7.6 to 10 kWh m⁻². Cooking pot placed in parabolic cooker was varied between 130 and 132 °C. Centre and south-east regions of study areas where global irradiation varied from 8 to 8.4 kWh m⁻² were found suitable for box-type solar cooker and cooking pot temperature were found in the range of 100 °C to 105 °C. Mathematical modelling was programmed in MATLAB. The theoretical results were consistent with experiential data for both types of solar cookers. The effectiveness of the two cooker types can be deduced from the maps. It is found the use of the cookers in Northern and Southern regions of the country was not identical. Their suitability for cooking depends on the amount of solar radiations received.

This investigation examines mathematical modelling and experimental validation of two types of solar cookers: a box type with tilted intercept area equipped with one external reflector, and a parabolic cooker with a new configuration. Experiments were carried out with the cookers filled with two kilograms of water from 08:00 to 15:00 solar time. During the experiments, temperature gain in the box-type solar cooker was recorded at about 69.8 °C and in the parabolic-type solar cooker at 73.6 °C at the stagnation point. Direct normal irradiation in three distinct study areas was observed and found that it varied from 7.6 to 10 kWh m⁻². Cooking pot placed in parabolic cooker was varied between 130 and 132 °C. Centre and south-east regions of study areas where global irradiation varied from 8 to 8.4 kWh m⁻² were found suitable for box-type solar cooker and cooking pot temperature were found in the range of 100 °C to 105 °C. Mathematical modelling was programmed in MATLAB. The theoretical results were consistent with experiential data for both types of solar cookers. The effectiveness of the two cooker types can be deduced from the maps. It is found the use of the cookers in Northern and Southern regions of the country was not identical. Their suitability for cooking depends on the amount of solar radiations received.

This investigation examines mathematical modelling and experimental validation of two types of solar cookers: a box type with tilted intercept area equipped with one external reflector, and a parabolic cooker with a new configuration. Experiments were carried out with the cookers filled with two kilograms of water from 08:00 to 15:00 solar time. During the experiments, temperature gain in the box-type solar cooker was recorded at about 69.8 °C and in the parabolic-type solar cooker at 73.6 °C at the stagnation point. Direct normal irradiation in three distinct study areas was observed and found that it varied from 7.6 to 10 kWh m⁻². Cooking pot placed in parabolic cooker was varied between 130 and 132 °C. Centre and south-east regions of study areas where global irradiation varied from 8 to 8.4 kWh m⁻² were found suitable for box-type solar cooker and cooking pot temperature were found in the range of 100 °C to 105 °C. Mathematical modelling was programmed in MATLAB. The theoretical results were consistent with experiential data for both types of solar cookers. The effectiveness of the two cooker types can be deduced from the maps. It is found the use of the cookers in Northern and Southern regions of the country was not identical. Their suitability for cooking depends on the amount of solar radiations received.

The magnetohydrodynamics (MHD) is an important interdisciplinary field. It is the interaction between an electromagnetic field and an electrically conducting fluid. Electromagnetic pumps are widely used for the transportation of the fluids in a variety of technological processes. The advantage of these devices is that permits the pumping of liquids without moving parts. The design of the pump is considered as an optimization problem where the objective function is the minimum of the MHD pump mass with both geometrical and electromagnetic contraints type. The obtained optimization results using the finite volume method with Matlab software show the performances of the used stochastic simulated annealing method.

The magnetohydrodynamics (MHD) is an important interdisciplinary field. It is the interaction between an electromagnetic field and an electrically conducting fluid. Electromagnetic pumps are widely used for the transportation of the fluids in a variety of technological processes. The advantage of these devices is that permits the pumping of liquids without moving parts. The design of the pump is considered as an optimization problem where the objective function is the minimum of the MHD pump mass with both geometrical and electromagnetic contraints type. The obtained optimization results using the finite volume method with Matlab software show the performances of the used stochastic simulated annealing method.

The magnetohydrodynamics (MHD) is an important interdisciplinary field. It is the interaction between an electromagnetic field and an electrically conducting fluid. Electromagnetic pumps are widely used for the transportation of the fluids in a variety of technological processes. The advantage of these devices is that permits the pumping of liquids without moving parts. The design of the pump is considered as an optimization problem where the objective function is the minimum of the MHD pump mass with both geometrical and electromagnetic contraints type. The obtained optimization results using the finite volume method with Matlab software show the performances of the used stochastic simulated annealing method.

The magnetohydrodynamics (MHD) is an important interdisciplinary field. It is the interaction between an electromagnetic field and an electrically conducting fluid. Electromagnetic pumps are widely used for the transportation of the fluids in a variety of technological processes. The advantage of these devices is that permits the pumping of liquids without moving parts. The design of the pump is considered as an optimization problem where the objective function is the minimum of the MHD pump mass with both geometrical and electromagnetic contraints type. The obtained optimization results using the finite volume method with Matlab software show the performances of the used stochastic simulated annealing method.

This paper designs an indirect power control method for brushless doubly fed induction generator (BDFIG), in which the stator is attached to grid with back-to-back space vector modulation (SVM) converter that converts the generated wind power. Our control method is a sliding mode control based on the theory of variable structure control. Specifically, the active and reactive powers, which are exchanged between the stator of the BDFIG and the grid in a linear and decoupled manner, are subjected to decoupled, vector control. In addition, a proportional integral (PI) controller was implemented to keep the DC-voltage constant for the back-to-back SVM converter. The efficiency of our control strategy was validated through simulation. The research greatly promotes the control of renewable energy generators.

This paper designs an indirect power control method for brushless doubly fed induction generator (BDFIG), in which the stator is attached to grid with back-to-back space vector modulation (SVM) converter that converts the generated wind power. Our control method is a sliding mode control based on the theory of variable structure control. Specifically, the active and reactive powers, which are exchanged between the stator of the BDFIG and the grid in a linear and decoupled manner, are subjected to decoupled, vector control. In addition, a proportional integral (PI) controller was implemented to keep the DC-voltage constant for the back-to-back SVM converter. The efficiency of our control strategy was validated through simulation. The research greatly promotes the control of renewable energy generators.

This paper designs an indirect power control method for brushless doubly fed induction generator (BDFIG), in which the stator is attached to grid with back-to-back space vector modulation (SVM) converter that converts the generated wind power. Our control method is a sliding mode control based on the theory of variable structure control. Specifically, the active and reactive powers, which are exchanged between the stator of the BDFIG and the grid in a linear and decoupled manner, are subjected to decoupled, vector control. In addition, a proportional integral (PI) controller was implemented to keep the DC-voltage constant for the back-to-back SVM converter. The efficiency of our control strategy was validated through simulation. The research greatly promotes the control of renewable energy generators.

This paper designs an indirect power control method for brushless doubly fed induction generator (BDFIG), in which the stator is attached to grid with back-to-back space vector modulation (SVM) converter that converts the generated wind power. Our control method is a sliding mode control based on the theory of variable structure control. Specifically, the active and reactive powers, which are exchanged between the stator of the BDFIG and the grid in a linear and decoupled manner, are subjected to decoupled, vector control. In addition, a proportional integral (PI) controller was implemented to keep the DC-voltage constant for the back-to-back SVM converter. The efficiency of our control strategy was validated through simulation. The research greatly promotes the control of renewable energy generators.

This paper deals with the robust power control of a grid-connected brushless doubly-fed induction generator (BDFIG) driven by the variable speed wind turbine. With the using of a super twisting algorithm which is a high-order sliding mode controller (HOSMC). This approach guarantees both the dynamic performance and the same robustness as traditional first order (SMC) algorithm and reduces the chattering phenomenon, which is the biggest disadvantage in the implementation of this technique. The developed algorithm relies on the decoupling control by implementing the strategy of oriented grid flux vector control. In order to enhance the desired performances, an attempt is made by controlling the generated stator active and reactive powers in a linear and decoupled manner to ensure the global asymptotical stability, HOSMC approach is implemented. Therefore, an optimal operation of the BDFIG in sub-synchronous operation is used in addition to the stator power flows where the stator power factor is kept in a unity. The suggested method is examined with the Matlab/Simulink software. The performances and the feasibility of the designed control are illustrated by simulation results.

This paper deals with the robust power control of a grid-connected brushless doubly-fed induction generator (BDFIG) driven by the variable speed wind turbine. With the using of a super twisting algorithm which is a high-order sliding mode controller (HOSMC). This approach guarantees both the dynamic performance and the same robustness as traditional first order (SMC) algorithm and reduces the chattering phenomenon, which is the biggest disadvantage in the implementation of this technique. The developed algorithm relies on the decoupling control by implementing the strategy of oriented grid flux vector control. In order to enhance the desired performances, an attempt is made by controlling the generated stator active and reactive powers in a linear and decoupled manner to ensure the global asymptotical stability, HOSMC approach is implemented. Therefore, an optimal operation of the BDFIG in sub-synchronous operation is used in addition to the stator power flows where the stator power factor is kept in a unity. The suggested method is examined with the Matlab/Simulink software. The performances and the feasibility of the designed control are illustrated by simulation results.

This paper deals with the robust power control of a grid-connected brushless doubly-fed induction generator (BDFIG) driven by the variable speed wind turbine. With the using of a super twisting algorithm which is a high-order sliding mode controller (HOSMC). This approach guarantees both the dynamic performance and the same robustness as traditional first order (SMC) algorithm and reduces the chattering phenomenon, which is the biggest disadvantage in the implementation of this technique. The developed algorithm relies on the decoupling control by implementing the strategy of oriented grid flux vector control. In order to enhance the desired performances, an attempt is made by controlling the generated stator active and reactive powers in a linear and decoupled manner to ensure the global asymptotical stability, HOSMC approach is implemented. Therefore, an optimal operation of the BDFIG in sub-synchronous operation is used in addition to the stator power flows where the stator power factor is kept in a unity. The suggested method is examined with the Matlab/Simulink software. The performances and the feasibility of the designed control are illustrated by simulation results.

Purpose The purpose of this paper is to validate a fuzzy risk graph model through a case study results carried out on a safety instrumented system (SIS). Design/methodology/approach The proposed model is based on an inference fuzzy system and deals with uncertainty data used as inputs of the conventional risk graph method. The coherence and redundancy of the developed fuzzy rules base are first verified in the case study. A new fuzzy model is suggested for a multi-criteria characterization of the avoidance possibility parameter. The fuzzy safety integrity level (SIL) is determined for two potential accident scenarios. Findings The applicability of the proposed fuzzy model on SIS shows the importance and pertinence of the proposed fuzzy model as decision-making tools in preventing industrial hazards while taking into consideration uncertain aspects of the data used on the conventional risk graph method. The obtained results show that the use of continuous fuzzy scales solves the problem of interpreting results and provides a more flexible structure to combine risk graph parameters. Therefore, a decision is taken on the basis of precise integrity level values and protective actions in the real world are suggested. Originality/value Fuzzy logic-based safety integrity assessment allows assessment of the SIL in a more realistic way by using the notion of the linguistic variable for representing information that is qualitative and imprecise and, therefore, ensures better decision making on risk prevention.

Purpose The purpose of this paper is to validate a fuzzy risk graph model through a case study results carried out on a safety instrumented system (SIS). Design/methodology/approach The proposed model is based on an inference fuzzy system and deals with uncertainty data used as inputs of the conventional risk graph method. The coherence and redundancy of the developed fuzzy rules base are first verified in the case study. A new fuzzy model is suggested for a multi-criteria characterization of the avoidance possibility parameter. The fuzzy safety integrity level (SIL) is determined for two potential accident scenarios. Findings The applicability of the proposed fuzzy model on SIS shows the importance and pertinence of the proposed fuzzy model as decision-making tools in preventing industrial hazards while taking into consideration uncertain aspects of the data used on the conventional risk graph method. The obtained results show that the use of continuous fuzzy scales solves the problem of interpreting results and provides a more flexible structure to combine risk graph parameters. Therefore, a decision is taken on the basis of precise integrity level values and protective actions in the real world are suggested. Originality/value Fuzzy logic-based safety integrity assessment allows assessment of the SIL in a more realistic way by using the notion of the linguistic variable for representing information that is qualitative and imprecise and, therefore, ensures better decision making on risk prevention.