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Magnetohydrodynamic flow of nanofluids and heat transfer between two horizontal plates in a rotating system have been examined numerically. In order to do this, the group method of data handling (GMDH)-type neural networks is used to calculate Nusselt number formulation. Results indicate that GMDH-type NN in comparison with fourth-order Runge–Kutta integration scheme provides an effective means of efficiently recognizing the patterns in data and accurately predicting a performance. Single-phase model is used in this study. Similar solution is used in order to obtain ordinary differential equation. The effects of nanoparticle volume fraction, magnetic parameter, wall injection/suction parameter and Reynolds number on Nusselt number are studied by sensitivity analyses. The results show that Nusselt number is an increasing function of Reynolds number and volume fraction of nanoparticles but it is a decreasing function of magnetic parameter. Also, it can be found that wall injection/suction parameter has no significant effect on rate of heat transfer.

Grinding is known as the most widely used method of forming borosilicate optical glass (BK7). Due to the brittle nature of the BK7 glass, the predominant mechanism of material removal will be fracture. So, the surface under grinding will have surface (surface roughness) and subsurface damage. These damages will cause a decrease in mechanical resistance and performance. Modeling of surface and subsurface damages due to the grinding process using cup grinding tool has not been subjected in recent investigations. To do this, the surface roughness effects are investigated by changes in grinding parameters such as cutting speed, feed rate, cutting depth and table speed. Moreover, based on the experiments, the relationship between surface roughness and grinding parameters is simulated and the average error was 5.77%. In the second phase of the experiments, angular polishing method is used and subsurface morphologies are investigated by SEM and the depths of these damages are measured. Experimental results are compared with that of the Li theoretical model. Based on the results, the experimental and theoretical results have well consistency. In the end, based on the Li model, a new model based on the relationship between subsurface damage and grinding parameters is conducted.