With the development and application of advanced design and manufacturing techniques in China, it has made a great progress of techniques in the industry of hydro turbine in the past 10 years. A brief introduction of the latest progress of the R&D and manufacturing is presented in this paper.

View full abstract

A centrifugal fan with forward curved blades can give a large angular momentum to the fluid, but it doesn't have better efficiency. In this paper, design method to get a shape of volute casing with the best performance was treated. The experiments and numerical calculations were done using 2 shapes of impellers and 21 shapes of volute casings. Pressure distributions along the volute casings were also measured. From these results it was made clear that there a magnifying angle and a circumferential angle be able to have the largest discharge and the best efficiency. From these results the design method of the best type of volute casing was considered. These results were also made sure by the results of numerical calculations.

View full abstract

In the design of heat exchanger, it is important to predict the frequency of vortex generated from the finned tube banks in forced convection. This paper described the characteristics of the vortex generation in the serrated finned tube banks with staggered arrangement in case of the different tube diameter and the different fin height. In consequence we clarified that three kinds of the vortex with the different frequencies (L, M, H type) generated in the low frequency region as well as the other type serrated finned tube banks, and that the fin height considerably effected on the Strouhal number. Further we proposed the equation for predicting the frequency of vortex generation in the serrated finned tube banks.

View full abstract

Characteristics of aerodynamics and noise in the centrifugal fan with inducer was investigated with respect to the two parameters: outlet angle and skew angle of the impeller. It is shown that the outlet angle considerably effects on the turbulent noise but the skew angle of the blade effects barely on that. From the view points of aerodynamics and specific noise level, the optimum value of the outlet angle is about 48 degree and that of the skew angle is about 10 degree. Moreover, we proposed a new method to calculate the width of wake which is an important parameter to controll the turbulent noise. We predicted the sound pressure level of the turbulent noise with the help of predicted width of wake and inlet relative velocity. The experimental values of the overall turbulent noise with L-weighting and A-weighting functions agreed well with predicted values.

View full abstract