Effect of Shape of Intake Valve with Different Number of Spiral Guides (Blades) When Changing Temperature in the Cylinder of Small-Sized Marine Engine Ch8.5/11

BACKGROUND: A review of the literature shows that the study of temperature distribution and the effect of pressure is an important basis for the design of the most wear-resistant and durable valves and significantly affects the choice of materials. Studying the temperature distribution inside valves at the pressure exerted on them during engine operation is experimentally a very time-consuming and demanding task. It is required to perform such calculations with software allowing to consider certain loads based the crankshaft rotation angle of the test sample. AIM: The object of the study was a valve of a factory-built small-sized marine engine and the same valves with a modified design and added spiral guides (screens, blades) to study the effect of temperature exerted on them depending on the crankshaft rotation. All studied valves had the homogeneous structural material. METHODS: To conduct the study, we used the finite element method implemented in the Ansys software, where a non-stationary thermomechanical calculation of valves with different designs made of homogeneous material was performed using the small-sized marine engine Ch8.5-11 valve with the subsequent analysis of the results, their study, and comparison. For the convenience of the solution, the study was divided into two parts. In this part, the influence of temperature during the operation of the small-sized marine engine Ch8.5/11 is studied; the future study will involve the transfer of the studied temperature fields to the pressure in the small-sized marine engine cylinder tested by the valves. RESULTS: At this stage, the finite element method was used to build and visualize the temperature fields of valves with different designs, to calculate the heat flux density, and to analyze the value of the spiral guides installed on the valves in relation to the temperature. As the calculation was non-stationary, we selected the highest test temperature stresses exerted on the valves during operation for the small-sized marine engine study. CONCLUSION: The simulation allowed to collect data on the temperature distribution inside valve trays of the studied 40X steel valves, which can be viewed at any time of the studied interval. The study of the heat flux in valves of different designs revealed that the heat flux increased in the valve with 3 blades (283.12 W/mm2) and the heat flux in the design with 6 blades was 281.49 W/mm2.