It is often required to know which roadway (adjustment roadway) resistances and how much values of the resis- tances should be changed to make the airflow rates in roadways (target roadways) to certain required va...It is often required to know which roadway (adjustment roadway) resistances and how much values of the resis- tances should be changed to make the airflow rates in roadways (target roadways) to certain required values in the practice of mine ventilation. In this case, the airflow rates of the target roadways and the resistances of the roadways other than the ad- justment roadways are the given conditions and the resistances of the adjustment roadways are the solutions to be found. No straightforward method to solve the problem has been found up to now. Therefore, trial and error method using the ventilation network analysis program is utilized to solve the problem so far. The method takes long calculation time and the best answer is not necessarily obtained. The authors newly defined "airflow element" as an element of the ventilation network analysis. The resistances that satisfy the airflow requirements can be calculated straight forwardly by putting the function of the airflow element into the ventilation network analysis. The air power required for the ventilation can be minimized while meeting the airflow requirements by the advanced application of the method. The authors made the computer program fulfill the method. The program was applied to actual ventilation network and it was found that the method is very practical and the time required for the analysis is short.展开更多
In this paper, a strategy is proposed in order to introduce in a realistic way wind generation into a HL11 (bulk power system) non sequential Monte Carlo adequacy study with economic dispatch. Thanks to the implemen...In this paper, a strategy is proposed in order to introduce in a realistic way wind generation into a HL11 (bulk power system) non sequential Monte Carlo adequacy study with economic dispatch. Thanks to the implemented solution, wind generation is consequently confronted to operational constraints related to high powered thermal units, nuclear parks or thermal machines with technical minimum value. Moreover, during each simulated system state, a DC load flow is also calculated in order to evaluate reinforcements optimizing the large scale integration of wind power production. The simulation tool modified during the present work is called Scanner and is the property of Tractebel Engineering (Gaz de France-Suez) company. It has been here applied to an academic test system: the Roy Billinton Test System (RBTS).展开更多
This paper presents a new design of a probe adjusting device intended to position pressure and temperature probes in a flow field. 5-hole, 3-hole and temperature probes can be moved in radial direction and freely rota...This paper presents a new design of a probe adjusting device intended to position pressure and temperature probes in a flow field. 5-hole, 3-hole and temperature probes can be moved in radial direction and freely rotated about their axis. The high actuation accuracy of 3.9 ktm in radial direction and 0.09~ in angular position is validated in a 2-stage-turbine test rig which is installed at the Institute of Power Plant Technology, Steam and Gas Turbines, RWTH Aachen University. To meet the challenge to calculate the efficiency of a turbo machine which is mainly influenced by the temperature, all probe adjusting devices are positioned simultaneously and controlled by the MAS (measuring acquisition system) so that the same radial position in each stage is measured at the same time. For this purpose a new program has been developed to synchronize actuation and measurement. The slim design of 60 mm width allows measurement between the stages of turbo machines with small axial distances between vane and blade. In addition a CFD/FEA shows how the design and combination of materials compensate the thermal expansion of the engine during operation. This allows a minimal safety distance of 0.2 mm between rotor and probe to enable measurement as close to the physical boundary as possible. The actuation accuracy is demonstrated with pressure, temperature and angle distribution plots. It is also shown that the resolution of the measuring points, and therefore the actuation distances, has a large impact on the flow field analysis and should be set as high as possible. However the measuring time has to be taken into account.展开更多
文摘It is often required to know which roadway (adjustment roadway) resistances and how much values of the resis- tances should be changed to make the airflow rates in roadways (target roadways) to certain required values in the practice of mine ventilation. In this case, the airflow rates of the target roadways and the resistances of the roadways other than the ad- justment roadways are the given conditions and the resistances of the adjustment roadways are the solutions to be found. No straightforward method to solve the problem has been found up to now. Therefore, trial and error method using the ventilation network analysis program is utilized to solve the problem so far. The method takes long calculation time and the best answer is not necessarily obtained. The authors newly defined "airflow element" as an element of the ventilation network analysis. The resistances that satisfy the airflow requirements can be calculated straight forwardly by putting the function of the airflow element into the ventilation network analysis. The air power required for the ventilation can be minimized while meeting the airflow requirements by the advanced application of the method. The authors made the computer program fulfill the method. The program was applied to actual ventilation network and it was found that the method is very practical and the time required for the analysis is short.
文摘In this paper, a strategy is proposed in order to introduce in a realistic way wind generation into a HL11 (bulk power system) non sequential Monte Carlo adequacy study with economic dispatch. Thanks to the implemented solution, wind generation is consequently confronted to operational constraints related to high powered thermal units, nuclear parks or thermal machines with technical minimum value. Moreover, during each simulated system state, a DC load flow is also calculated in order to evaluate reinforcements optimizing the large scale integration of wind power production. The simulation tool modified during the present work is called Scanner and is the property of Tractebel Engineering (Gaz de France-Suez) company. It has been here applied to an academic test system: the Roy Billinton Test System (RBTS).
文摘This paper presents a new design of a probe adjusting device intended to position pressure and temperature probes in a flow field. 5-hole, 3-hole and temperature probes can be moved in radial direction and freely rotated about their axis. The high actuation accuracy of 3.9 ktm in radial direction and 0.09~ in angular position is validated in a 2-stage-turbine test rig which is installed at the Institute of Power Plant Technology, Steam and Gas Turbines, RWTH Aachen University. To meet the challenge to calculate the efficiency of a turbo machine which is mainly influenced by the temperature, all probe adjusting devices are positioned simultaneously and controlled by the MAS (measuring acquisition system) so that the same radial position in each stage is measured at the same time. For this purpose a new program has been developed to synchronize actuation and measurement. The slim design of 60 mm width allows measurement between the stages of turbo machines with small axial distances between vane and blade. In addition a CFD/FEA shows how the design and combination of materials compensate the thermal expansion of the engine during operation. This allows a minimal safety distance of 0.2 mm between rotor and probe to enable measurement as close to the physical boundary as possible. The actuation accuracy is demonstrated with pressure, temperature and angle distribution plots. It is also shown that the resolution of the measuring points, and therefore the actuation distances, has a large impact on the flow field analysis and should be set as high as possible. However the measuring time has to be taken into account.