It is common for an aircraft to encounter icing weather conditions, which would be dangerous to the flight. Thus, there is a need to study the detail of icing effect and the process of ice accretion on the aircraft. I...It is common for an aircraft to encounter icing weather conditions, which would be dangerous to the flight. Thus, there is a need to study the detail of icing effect and the process of ice accretion on the aircraft. In this paper, considering three different icing models according to weather conditions, i.e., sharp-angled ice, blunt-nosed ice and double horn ice, the Reynolds-averaged N-S equations and the S-A turbulence model are used to analyze the flow field for an iced wing/body configuration with a multi-block strategy and structured grid technique. The numerical result is compared with the experimental data. A flow solver is developed based on the Euler equations to investigate the ice accretion process. The droplets are tracked by using the Lagrangian method. In addition, a revised Messinger model is proposed to simulate the ice accretion. This numerical simulation is conducted for the ice accretion on an M6 wing and a wing/body/tail configuration. The presented results preliminarily show that the numerical methods are feasible and effective.展开更多
Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage...Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier studies.To reanalyze this problem and make it beyond argument,every possible variable is considered using theoretical analysis,not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths,parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and source region.Since N-well regions are commonly connected to the same power supply,these kinds of structures will not be a problem in a real CMOS integrated circuit.Generally speaking,conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical circumstances are not very sensitive to the total ionizing dose effect.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 11072201)the Aeronautic Science Foundation of China (Grant No. 2011ZA53006)
文摘It is common for an aircraft to encounter icing weather conditions, which would be dangerous to the flight. Thus, there is a need to study the detail of icing effect and the process of ice accretion on the aircraft. In this paper, considering three different icing models according to weather conditions, i.e., sharp-angled ice, blunt-nosed ice and double horn ice, the Reynolds-averaged N-S equations and the S-A turbulence model are used to analyze the flow field for an iced wing/body configuration with a multi-block strategy and structured grid technique. The numerical result is compared with the experimental data. A flow solver is developed based on the Euler equations to investigate the ice accretion process. The droplets are tracked by using the Lagrangian method. In addition, a revised Messinger model is proposed to simulate the ice accretion. This numerical simulation is conducted for the ice accretion on an M6 wing and a wing/body/tail configuration. The presented results preliminarily show that the numerical methods are feasible and effective.
文摘Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier studies.To reanalyze this problem and make it beyond argument,every possible variable is considered using theoretical analysis,not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths,parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and source region.Since N-well regions are commonly connected to the same power supply,these kinds of structures will not be a problem in a real CMOS integrated circuit.Generally speaking,conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical circumstances are not very sensitive to the total ionizing dose effect.
