the rectangular cross-section scroll for a radial turbine was designed. A commercial computational fluid dynamics software CFX was used to caculate the flow losses within the radial turbine with the scroll. Then
the numerical caculation result was compared with that of the radial turbine with chamber. The results show that the loss within the scroll is less than that in chamber. The flow in the radial turbine with scroll is better than that of the turbine with chamber. The radial turbine with scroll has a higher efficiency than the radial turbine with chamber. The power of the radial turbine will increase by 1.7% when using the rectangular cross-section scroll. The inner flow field and losses mechanism is revealed by analyzing the flow field
in order to provide some reference for further development of radial turbine.