In this project, an internal flow radiator has been simulated. Radiators are one of the critical components in the cooling system of the automotive industry. These devices are used in car design to transfer the heat generated by various car components to the outside of the engine and different car parts. By doing this, radiators prevent the engine from heating up and damaging engine parts and other parts when the car is on. In this radiator, water coolant is used to cool the oil. The inlet water temperature is 290 Kelvin, and the inlet oil temperature is 370 Kelvin. In internal flow radiators, one fluid is cooled by another fluid using heat transfer. However, in other radiators, water or oil is cooled by outside airflow.
Because the heat transfer coefficient of liquids is higher than gases, using a liquid coolant can increase the heat transfer rate and achieve lower temperatures. Therefore, internal flow radiators have higher efficiency than external flow radiators. The use of CFD simulation in the design of these radiators helps us a lot. We can simulate and analyze different tube arrangements and diameters inside the radiator before the final design and construction and choose the most optimal one for the building.
The geometry of this project has been designed using Space Claim software. The Ansys Meshing software has meshed this geometry, and the number of elements used for this project is 686912.
Heat transfer is being investigated in this simulation, so the energy equation must be activated. The turbulence model used for this simulation is the Realizable k-epsilon model. This model is suitable for simulating heat transfer.
After the simulation, we see that the oil, which has a temperature above 370 K at the inlet, gradually transfers heat with the cold water as it moves along its path, decreasing its temperature. Finally, after traveling all the way, the temperature at the outlet reaches 324 degrees K. To reach lower temperatures for the oil, we can use longer internal pipes in the radiator to increase the area where heat transfer occurs. We can also optimize the optimal diameter for the tubes to achieve a higher Nusselt and convection heat transfer coefficient. Finally, the heat transfer between water and oil has reached 294 degrees K.