Alireza Dehghani-Sanij

Analysis of Ice Accretion on Vertical Surfaces of Marine Vessels and Structures in Arctic Conditions

The phenomenon of icing in cold climates is a challenging problem of engineering analysis, which involves heat transfer, phase change and multiphase flow with water droplets. This phenomenon has an important impact on the performance and operation of marine vessels, offshore structures, and others such as wind turbines, power lines, and aircraft surfaces. In this paper, a predictive icing model for large vertical surfaces of a marine vessel is developed theoretically. The total flux of sea-spray, including wave spray and wind spray, is analyzed during the spray process. By using heat, mass and salt concentration balances, the freezing fraction, temperature distribution, ice layer thickness, and liquid film thickness are determined. The results are compared with the numerical and experimental results of other studies. Good agreement between the theoretical predictions and other results demonstrates the improved accuracy of the proposed method over past models.© 2015 ASME

Numerical Investigation of Thermal Resistance in a Rectangular Flux Channel With Non-Uniform Heat Convection in the Sink Plane

Thermal analysis of electronic devices is essential for designing thermal management systems and for assuring a perfect working condition. In order to have a precise thermal analysis, thermal spreading resistance should be calculated. In this paper, a numerical study is conducted on the thermal resistance of a 2D flux channel with a non-uniform convection coefficient in the heat sink plane. For this purpose, the Finite Volume Method (FVM) is used. As a case study, a 2D flux channel with a discrete specified heat flux and convection edges is assumed. Also, the heat transfer coefficient in the sink boundary condition is determined symmetrically using a hyperellipse function. This function can model a wide variety of different distributions of a heat transfer coefficient from a uniform cooling to the most intense cooling in the central region. All results are compared and validated with the COMSOL commercial software package. The proposed method is useful for thermal engineers for modeling different flux channels with different properties and boundary conditions such as the variable heat transfer coefficient.Copyright