Printed circuit heat exchangers (PCHE) play a critical role in the performance and layout sizing of the new supercritical CO2 power cycle. The current study aims to predict the thermal and hydraulic performance of the new geometry of sCO2 PCHE. In this new geometry, conventional zig zag geometry has been replaced with the new channel geometry that is based on the curve of the cosine function. The new geometry has eliminated the recirculation zones that result in regions with low rates of heat transfer. Boundary reinitialization has been achieved by a discontinuous fin structure. Thermal and hydraulic performance of the printed heat exchanger were evaluated using the commercial ANSYS-CFX code. The computational model was validated by using conventional geometry and comparing numerical results with published correlations. Discretization of the computation domain was conducted using ANSYS ICEM-CFD and ANSYS-Mesh. Properties of supercritical carbon dioxide (sCO2) were computed using an in-house Matlab code that was linked with NIST Refprop. The same code was used to write the properties in the real gas property (rgp) table which was then supplied to ANSYS CFX in rgp file format.

This study investigates the effect of using A/C refrigerant to reduce the temperature of the coolant in a vehicle cooling system. An increase in coolant temperature due to harsh working conditions increases fuel consumption and leads to a reduction in engine power. Modifying vehicle air-conditioning by passing the suction line of the A/C system through the heat exchanger located in the lower part of the radiator (down flow type) can significantly improve the performance of the engine cooling system. The results show a reduction in the temperature of coolant within the cooling system, thus maintaining a controlled working temperature within the allowable limits.

The present article discusses the effect of high concentration at upper vertical surface in a square porous cavity. The right vertical surface is maintained at constant concentration Cc such that Cw>Cc. The left and right vertical surfaces of cavity are maintained at isothermal temperature Tw and Tc where Tw>Tc. The governing momentum, energy and concentration equations are converted into algebraic form of equations using finite element method. The domain is meshed with triangular elements with proper care to capture the high degree of nonlinearity at the boundaries of square cavity. Results are discussed with respect to Lewis number, buoyancy ratio and Rayleigh number.

In spite of the huge success of computational chemistry in corrosion studies, most of the ongoing research on the inhibition of preferential weldcorrosion is restricted to laboratory work. In the present study, a nondeterministic artificial intelligence model is proposed, the aim being to more accurately predict the occurrence of corrosion in the Heat Affected Zone (HAZ), which is most exposed to corrosion risk. The prediction of corrosion rates has become an important challenge for the engineering community. For industry, one of the more important aspects of corrosion is the HAZ for welded carbon steel in CO2 environments. Nowadays, data from various sources (e.g., temperature and velocity), for both inhibited and non-inhibited CO2 solutions, can be fed into neural networks, allowing them to be used for data processing. An artificial neural network is proposed for the prediction of corrosion in the HAZ.A phenomenal outcome for the prediction of corrosion in the HAZ was proposed with the learning ability of an artificial neural network using software, through which training of 406 sets of data using the Leven Berg-Marquardt algorithm were obtained from experimental data. The training sets were developed for three levels of corrosion (mild, moderate and severe) through the Artificial Neural Network (ANN) and resulted in a trend which took the form of an incremental parabolic curve. This study presents an artificial neural network model which simulates the complex and nonlinear atmospheric corrosion process observed in experimental data. The correlation statistics (R) in the ANN proved to be 90% accurate. The test results were validated to confirm the efficacy of the developed ANN model for prediction of corrosion rate and good performance was observed. The interactions between the inputs were estimated by performing a sensitivity analysis based on the developed model. Since the model results from this research showed good agreement with experimentally obtained corrosion rates, it could now be widely applied in corrosion studies.

In this study the aim is to study the unsteady mixed convection flow of viscous incompressible fluid through a horizontal channel embedded in non-Darcy porous medium with Brinkman-extended Darcy drag, assuming that temperature of the lower wall varies sinusoidally in the direction of the flow and that of the upper wall is uniform. The governing equations of the flow in terms of vorticity equation and energy equations are simulated using the lattice Boltzmann method together with the finite difference successive over relaxation method. The results are presented in terms of streamlines and isotherms showing the effect of Darcy drag and the Forchheimer drag as well as average Nusselt number. The observation from the present investigation is that the average Nusselt number decreases due to increase of the Darcy and Forchheimer drags, which leads to disappearance of the separated flow that developed for the flow of pure fluid as well as reduces the temperature along the heated region of the lower surface, although the periodicity of the wave propagation remains the same but amplitude of oscillation diminishes.