Force and Efficiency Analyses of the Vertical Shaft Type Wind-Power Chinese Square-Pallet Chain-Pump
This study is a continuation of the project which is called "Reconstruction and Manufacture of Vertical shaft type wind-power Chinese square-pallet chain-pumps". This study made force and efficiency analyses of vertical shaft type wind-power Chinese square-pallet chain-pumps, and then designed an experiment of Chinese square-pallet chain-pumps, through the experimental data and analysis, made up the ancient books described deficiencies.
A vertical shaft type wind-power Chinese square-pallet chain-pump is a kind of Chinese square-pallet chain-pump which is driven by a vertical shaft type windmill. Vertical shaft type windmill is an unique power machine in the world, can be driven by wind of any direction, but there is still no efficient research of that unique power machine. This study assuming winds as ideal fluids to give a force on a sail by Bernoulli's equation, also use Tip Speed Rate to make an observation of the change of rotation speed with the working interval of a motion cycle. We can get the limit positions of the sail with best starting torque and best efficiency in this study.
Chinese square-pallet chain-pumps have different types of human powered, animal powered, hydro powered, and wind powered. Although Chinese square-pallet chain-pumps were important pumping devices in ancient China and its surrounding areas, actual irrigation efficiency in the ancient records was extremely simple. Therefore this study designed a "Multi-type Chinese square-pallet chain-pump" which can replace its parts to change parameters of efficiency or pumping capacity. According to these parameters, we can make an experiment, and know that water flow rate will be affected by the operation speed, placing slope of chain-pumps, size of square-pallets and seamless of square-pallets. The conclusion is efficiency of Chinese square-pallet chain-pumps most affected by size of square-pallets.
Mechanical efficiency of Chinese square-pallet chain-pumps can be increased to about 65% from 50% when size of square-pallets are multiplied by 1.66.Furthermore, according to the experimental results can be informed that the operation power of Chinese square-pallet chain-pumps. So we can estimate the power of the Chinese square-pallet chain-pump is 235W when rotation speed of windmill is 3 rpm. In fact that the actual output power of the windmill still need to consider the transmission loss of power, it must be greater than 235W.