Important Measures to Improve the Performance of LPG Public Bus Engines

The layout of radiators, fans and air intake compartment partitions in the current engine room is not reasonable. If there is a vortex in front of the radiator, L1(2) in the air flow L1 from the fan cannot flow to the B area where the engine is operating, ie air flow. L1 is not fully utilized, and the actual flow to the engine working area is small, and the flow rate is low, resulting in a problem of poor convective heat transfer efficiency and poor heat dissipation in the engine room. Improvements in the layout of the engine room may consider shifting the orientation of components such as radiators and fans, changing the fan to face the engine body rather than the rear door, and remove the air intake compartment partition in area A, which can effectively The use of high-speed air flow from the fan to achieve the purpose of improving convection heat transfer efficiency in the cabin and improving cabin heat dissipation performance.

Using CFD and engineering heat transfer numerical analysis methods, the air flow vector diagram and the temperature distribution cloud diagram in the flow field of the engine compartment of a certain type of LPG gas bus were obtained, and the main high-temperature components in the engine room were analyzed to have a radiator. Intercoolers, engine blocks, turbochargers, etc., their heat is transferred to the engine compartment by the thermal convection of air. The layout of the components in the engine compartment, especially the position of various partitions and fans in the cabin, is one of the key factors causing the heat dissipation characteristics of the engine compartment. Therefore, the engine compartment design based on the automotive air heat transfer dynamics is one of the important measures to improve the performance of the LPG public bus engine.