We report on numerical studies of bounded double-diffusive turbulent convection, which involves the combined effects of concentration/solutal and thermal buoyancy forces. Our study focuses on an intermediate range of the characteristic non-dimensional numbers, specifically 107≤Rac≤109, and 0≤Raθ≤106. We use fixed values for the concentration and temperature Prandtl numbers (i.e. Prc=700, Prθ = 7), which approximately correspond to seawater properties. We apply wall-resolved Large Eddy Simulations (LES) and compare the obtained results with available Direct Numerical Simulations (DNS) in the literature. Our findings show an overall good agreement in predicting the global wall mass and heat transfer coefficients, achieved with significantly reduced computational costs. Furthermore, the local mass and heat transfer distributions reveal a high sensitivity to the strength of the vertically imposed stable thermal stratification. Finally, we present the vertical profiles of the long-term time-averaged first and second moments.@en

The present study addresses numerical simulations of the double-diffusive convection in a turbulent regime. The characteristic concentration and temperature Prandtl numbers (PrC = 700 and PrT = 7) correspond to the typical seawater properties. Here, we applied the Large-Eddy Simulation (LES) approach, with relatively simple subgrid turbulence closures of momentum, concentration, and temperature for the unresolved scales. The wall-resolved LES approach proved to work well on significantly coarser numerical mesh than used in recent Direct Numerical Simulation (DNS) studies of Yang et al. (2016) in the intermediate range of working parameters, 107 ≤ RaC ≤ 109, 0 ≤ RaT ≤ 106, which covers the quasi-Rayleigh-Bénard, fingering, and damping flow regimes. A good agreement between concentration and temperature Nusselt numbers is obtained. The instantaneous Nusselt numbers distribution revealed a significant impact of the imposed strong thermal stratification (RaT = 106) in comparison to the neutral case (RaT = 0).

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A single-bit fifth-order complex continuous-time IF-to-baseband SigmaDelta modulator for AM/FM/IBOC receivers is presented. The input IF is 10.7 MHz and the sampling frequency is 41.7 MHz. The modulator achieves a dynamic range of 118dB in AM mode (3 kHz BW), 98dB in FM mode (200 kHz BW), and 86dB in IBOC mode (500 kHz BW). The modulator's high dynamic range enables the realization of an AM radio receiver without a VGA and without an AM channel-selection filter, thereby reducing system complexity and cost. The elimination of the VGA also improves the sensitivity and the overall noise figure of the receiver. The modulator's spurious free dynamic range is 88 dB in the bandwidth from 25 to 525 kHz. The IM2 distance is 92 dB, and the IM3 distance is 91 dB. The ADC was fabricated in a one-poly five-metal 0.18-mum CMOS process with an active area of 6.0mm2. It consumes 210 mW from a 1.8-V supply@en