Fault location on one of two parallel lines is determined as a percentage of line length in the presence and absence of the mutual effect between lines. The methodology for fault location is based on the principle that at the fault E f1 +E f2 +E f0 = 0. This relation is utilized to determine the sequence voltages at the relay position, where the impedance to the fault location can be assessed. This makes it possible to devise new accurate algorithms for fault location, whatever the lines are fed from one end or both ends. The location of single line-to-ground (SLG) and double line-to-ground (DLG) faults at different points along the line is investigated. With the determination of the fault location, the impedance seen by the distance relay is defined for SLG and DLG faults. This impedance determines where the fault is within the reach of the relay.

New accurate algorithms based on mathematical modeling of two parallel transmissions lines system (TPTLS) as influenced by the mutual effect to determine the fault location is discussed in this work. The distance relay measures the impedance to the fault location which is the positive-sequence. The principle of summation of the positive-, negative-, and zero-sequence voltages which equal zero is used to determine the fault location on the TPTLS. Also, the impedance of the transmission line to the fault location is determined. These algorithms are applied to single-line-to-ground (SLG) and double-line-to-ground (DLG) faults. To detect the fault location along the transmission line, its impedance as seen by the distance relay is determined to indicate if the fault is within the relay’s reach area. TPTLS under study is fed from one- and both-ends. Schematic diagrams are obtained for the impedance relays to determine the fault location with high accuracy.

Channel-based microfluidics was proven to be a helpful platform for reproducible preparation of nanoparticles (NPs), where controlled mixing of fluids allows homogeneous and tuned process of NPs formation. Nanoprecipitation is a popular method for polymeric NPs formation based on controlled precipitation of a polymer upon mixing of two miscible solvents. Conventionally, flow rate, flow rate ratio and polymer concentration have been utilized to control NPs size and polydispersity. However, minimum attention has been given to the effect of channel geometry on nanoprecipitation process. In our study, we investigated the effect of channel geometry and design on the size and polydispersity index (PDI) of poly (lactic-co-glycolic) acid (PLGA) NPs. Ten different designs with varied channel length, aspect ratio, number of interfaces and channel curvature were fabricated and tested. These variations were introduced to modify the diffusion rate, the interface area or to introduce Dean flow, all of which will change the mixing time . The effects of these variations were compared to that of different flow parameters. Change in channel length did not have a significant effect on particle size. However, increasing the diffusion area and reducing significantly reduced NPs’ size. Moreover, when curvature was introduced into the channel, mixing was enhanced, and particle size was decreased in a manner dependent on the velocity of the generated Dean flow. While different flow parameters continue to be the main approach for adjusting NPs properties, we demonstrate that channel geometry modification enables tuning of NPs’ size using simple designs that can be easily adapted.

Channel-based microfluidics was proven to be a helpful platform for reproducible preparation of nanoparticles (NPs), where controlled mixing of fluids allows homogeneous and tuned process of NPs formation. Nanoprecipitation is a popular method for polymeric NPs formation based on controlled precipitation of a polymer upon mixing of two miscible solvents. Conventionally, flow rate, flow rate ratio and polymer concentration have been utilized to control NPs size and polydispersity. However, minimum attention has been given to the effect of channel geometry on nanoprecipitation process. In our study, we investigated the effect of channel geometry and design on the size and polydispersity index (PDI) of poly (lactic-co-glycolic) acid (PLGA) NPs. Ten different designs with varied channel length, aspect ratio, number of interfaces and channel curvature were fabricated and tested. These variations were introduced to modify the diffusion rate, the interface area or to introduce Dean flow, all of which will change the mixing time . The effects of these variations were compared to that of different flow parameters. Change in channel length did not have a significant effect on particle size. However, increasing the diffusion area and reducing significantly reduced NPs’ size. Moreover, when curvature was introduced into the channel, mixing was enhanced, and particle size was decreased in a manner dependent on the velocity of the generated Dean flow. While different flow parameters continue to be the main approach for adjusting NPs properties, we demonstrate that channel geometry modification enables tuning of NPs’ size using simple designs that can be easily adapted.

Channel-based microfluidics was proven to be a helpful platform for reproducible preparation of nanoparticles (NPs), where controlled mixing of fluids allows homogeneous and tuned process of NPs formation. Nanoprecipitation is a popular method for polymeric NPs formation based on controlled precipitation of a polymer upon mixing of two miscible solvents. Conventionally, flow rate, flow rate ratio and polymer concentration have been utilized to control NPs size and polydispersity. However, minimum attention has been given to the effect of channel geometry on nanoprecipitation process. In our study, we investigated the effect of channel geometry and design on the size and polydispersity index (PDI) of poly (lactic-co-glycolic) acid (PLGA) NPs. Ten different designs with varied channel length, aspect ratio, number of interfaces and channel curvature were fabricated and tested. These variations were introduced to modify the diffusion rate, the interface area or to introduce Dean flow, all of which will change the mixing time . The effects of these variations were compared to that of different flow parameters. Change in channel length did not have a significant effect on particle size. However, increasing the diffusion area and reducing significantly reduced NPs’ size. Moreover, when curvature was introduced into the channel, mixing was enhanced, and particle size was decreased in a manner dependent on the velocity of the generated Dean flow. While different flow parameters continue to be the main approach for adjusting NPs properties, we demonstrate that channel geometry modification enables tuning of NPs’ size using simple designs that can be easily adapted.

Channel-based microfluidics was proven to be a helpful platform for reproducible preparation of nanoparticles (NPs), where controlled mixing of fluids allows homogeneous and tuned process of NPs formation. Nanoprecipitation is a popular method for polymeric NPs formation based on controlled precipitation of a polymer upon mixing of two miscible solvents. Conventionally, flow rate, flow rate ratio and polymer concentration have been utilized to control NPs size and polydispersity. However, minimum attention has been given to the effect of channel geometry on nanoprecipitation process. In our study, we investigated the effect of channel geometry and design on the size and polydispersity index (PDI) of poly (lactic-co-glycolic) acid (PLGA) NPs. Ten different designs with varied channel length, aspect ratio, number of interfaces and channel curvature were fabricated and tested. These variations were introduced to modify the diffusion rate, the interface area or to introduce Dean flow, all of which will change the mixing time . The effects of these variations were compared to that of different flow parameters. Change in channel length did not have a significant effect on particle size. However, increasing the diffusion area and reducing significantly reduced NPs’ size. Moreover, when curvature was introduced into the channel, mixing was enhanced, and particle size was decreased in a manner dependent on the velocity of the generated Dean flow. While different flow parameters continue to be the main approach for adjusting NPs properties, we demonstrate that channel geometry modification enables tuning of NPs’ size using simple designs that can be easily adapted.

Channel-based microfluidics was proven to be a helpful platform for reproducible preparation of nanoparticles (NPs), where controlled mixing of fluids allows homogeneous and tuned process of NPs formation. Nanoprecipitation is a popular method for polymeric NPs formation based on controlled precipitation of a polymer upon mixing of two miscible solvents. Conventionally, flow rate, flow rate ratio and polymer concentration have been utilized to control NPs size and polydispersity. However, minimum attention has been given to the effect of channel geometry on nanoprecipitation process. In our study, we investigated the effect of channel geometry and design on the size and polydispersity index (PDI) of poly (lactic-co-glycolic) acid (PLGA) NPs. Ten different designs with varied channel length, aspect ratio, number of interfaces and channel curvature were fabricated and tested. These variations were introduced to modify the diffusion rate, the interface area or to introduce Dean flow, all of which will change the mixing time . The effects of these variations were compared to that of different flow parameters. Change in channel length did not have a significant effect on particle size. However, increasing the diffusion area and reducing significantly reduced NPs’ size. Moreover, when curvature was introduced into the channel, mixing was enhanced, and particle size was decreased in a manner dependent on the velocity of the generated Dean flow. While different flow parameters continue to be the main approach for adjusting NPs properties, we demonstrate that channel geometry modification enables tuning of NPs’ size using simple designs that can be easily adapted.

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