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The geometry of a curved diffuser often inviting the flow to separate. The flow separation phenomenon plays a vital role in the recovery of pressure inside the diffuser. Besides, the geometrical and operating aspects of a curved diffuser have always been taken into consideration in most relatable researches. Pressure recovery and flow uniformity of a steady, developed entering turbulent flow of a circularsectioned 180° curved diffuser has been investigated numerically by varying geometrical and operating parameters. The curved diffuser with area ratio (2, 3 and 4), radius of inlet and curvature of respectively 50 mm and 180 mm was considered. Different values of Reynolds number 6 × 10 4 , 12 × 10 4 , 18 × 10 4 , 24 × 10 4 , and 30 × 10 4 were tested in every area ratio set. ANSYS code Fluent was used to run the simulation by considering different turbulence models, i.e. the standard kturbulence model (std k-), Spalart-Allmaras turbulence model (SA), k-kl-transition turbulence model and transition SST model. The present work proposed the curved diffuser with AR=2 operated at Re=6x10 4 as the optimum set of parameters, with minimal flow separation occurring in the system.

Breast cancer is one of the leading critical illnesses in Malaysia. Typically, patients would undergo a lumpectomy or mastectomy followed by chemotherapy and radiotherapy. However, these treatments have side effects that impact the quality of life. Hyperthermia is a treatment that can kill the tumour with less effect on the other parts of the body. From previous findings, heating the body to a temperature of 40°C to 46°C is an alternative procedure to reduce the side effect of these treatments. This study aims to investigate heat propagation into malignant tumours of different sizes. Three different models of breast tumours with different sizes were modelled. The heat propagation was simulated using the computational fluid dynamic (CFD) method. Three different temperatures were applied to the malignant tumours exposed to infrared and thermocouple heat sources. From the observation, model 14mm demonstrated the highest temperature propagation as compared to the others. The heat propagation in the blood vessel also showed a significant radiation effect as shown in the tumour. However, the velocity and pressure in the blood vessel have no significant changes for all models. In conclusion, the heat propagation via infrared sources managed to penetrate the tumours and the early stage of the tumour experienced better heat propagation as compared to thermocouples.