Numerical modeling and parametric study of an innovative solar oven

Abstract

The ability to accurately predict vortex shedding around wind turbine blades is paramount, particularly at high Reynolds number. Turbulence models employed in the numerical studies strongly influence flow separation and the aerodynamic loading, thus affecting the overall accuracy of numerical simulations. In this manuscript, three turbulence models (Spalart-Allmaras, k − and k − ω Shear Stress Transport model) are investigated in two and three dimensional configurations using standard Reynolds Average Navier-Strokes equations. The focus is on the NACA0015 airfoil, and the simulations are conducted at a Reynolds number of 1.96 × 10 6 to match the experimental data in the literature. The effect of flow separation and vortex shedding pattern is investigated at different angles of attack (0°≤ α ≤ 17°,) along with the prediction ability of the turbulence models. Spectral analysis is performed over the time history of aerodynamic coefficients to identify the dominant frequencies along with their even and odd harmonics. A reduced-order model based on the van der Pol equation is proposed for the aerodynamic lift calculation. The method of multiple scales (a perturbation approach) is adapted to compute the coefficients of the proposed model consisting of quadratic and cubic non-linearities at the various angle of attacks (α). The model is also tested in a predictive setting, and the results are compared against the full order model solution.

Solar cooking potential in Switzerland: Nodal modelling and optimization

“…The model seems to be in good accordance with the experimental data in particular as compared to the maximum temperature obtained. This is comparable to results from Zafar et al (2019) and the error range between the simulated and measured values are also in line with previous studies (Guidara et al, 2017). The focus has mainly been on the results with a water load, which represents the principal situation in which the oven will be practically used.…”

Numerical Analysis of Concentrated Solar Heaters for Segmented Heat Accumulators

“…The design combines the features of a solar radiation collector that utilizes a revolving compound parabolic concentrator and channel. In the presented tests, the solar cooker part of the device achieved a heat output of 150 W. Zafar et al [36] presented a new design of a solar cooker using the upper, lower, and front reflective surface. In the experiment, the new device reached a temperature of 100 • C-135 • C in 1 to 1.5 h. Ayub et al [37] focused on increasing the power of a solar cooker.…”