Single theory of movers on continuous flows. Short theory of counterturn screws

Abstract

The article presents the developed brief theory of counterturn screws, which is a logical chain of a series of articles relating to the formation of the theory of short-row screws, the brief theory of counterturn screws, the brief theory of co-turn screws, the comparative analysis of single row, counterturn and co-turn screws, in order to select the most effective option. It was shown that counterturn screws have large energy costs and very low traction efficiency, 35% and 5.7% respectively in the first and the second impeller. Based on the above, the ultimate goal of a series of articles will be: to show and to prove that among single-row, counterturn and co-turn screws the most effective are co-turn screws.  They permit to eliminate the main drawback of single and counterturn screws, related to the presence of kinematic zone of elastic impact, Figure 1, section B1-B1, generating into the space powerful shock waves in an oscillatory mode. The next drawback of  counterturn screws is the twist of the stream of the first impeller, which regulates the counter twist of flow at the input to the second counterturn impeller, which, in turn, regulates the increased hydrodynamic loads on the troughs of the blades of the second counterturn impeller and its low speed compared to the first . Therefore, the next article will cover the creation of a brief theory of co-turn screws, which will present their full analysis