Good Price Diesel Pump Head Rotor 096400-0232 Fuel Injection Pump Elements Engine Spare Parts

Abstract
Flow pulsation in pump heads is a critical factor influencing fuel injection stability, pressure regulation, and system efficiency in high-pressure fuel and hydraulic systems. Under elevated pressures, unsteady flow phenomena become more pronounced, leading to cavitation, vibration, and efficiency losses. This study investigates the mechanism of flow pulsation in pump heads under high-pressure conditions through computational fluid dynamics (CFD) analysis and experimental observation.

1. Introduction
Modern high-pressure fuel injection systems demand precise and stable delivery of fuel to achieve optimal combustion efficiency and low emissions. However, inherent design features of the pump head, including plunger reciprocation, valve dynamics, and restricted flow passages, cause transient fluctuations in flow rate. Understanding the pulsation mechanism is therefore essential for optimizing pump head structure and improving system reliability.

2. Mechanism of Flow Pulsation
Flow pulsation arises primarily from periodic variations in the effective displacement of the plunger and dynamic response of the delivery valve. As the plunger moves upward, fuel is rapidly compressed, producing steep pressure gradients and sudden discharge into the outlet channel. When the valve closes, reverse flow and cavitation bubbles may occur, further amplifying pulsation. Additionally, elastic deformation of the fuel and compressibility effects under high pressure contribute to oscillatory flow patterns.

3. Numerical Simulation
A transient CFD model of the pump head was developed to capture pulsation characteristics. The moving mesh approach was employed to represent plunger and valve motion, while the cavitation model accounted for vapor bubble formation and collapse. Results revealed that pulsation intensity increased with higher injection pressures due to enhanced fuel compressibility. Pressure wave propagation within the outlet passage was also identified as a significant factor influencing pulsation amplitude and frequency.

4. Experimental Validation
A high-pressure test bench was constructed to measure flow pulsation. Pressure sensors and flow meters recorded transient signals, while high-speed visualization captured cavitation events near the valve seat. Experimental data confirmed that pulsation frequency corresponded to the plunger reciprocation frequency, while amplitude increased nonlinearly with pressure. The results were consistent with CFD predictions, validating the accuracy of the simulation model.

5. Discussion
The study shows that flow pulsation is influenced by both structural parameters and operating conditions. Valve lift height, spring stiffness, and clearance dimensions significantly affect pulsation amplitude. At extremely high pressures, fuel compressibility dominates the pulsation mechanism, while cavitation plays a secondary role by introducing additional fluctuations. Structural optimization, such as improving valve seat geometry and damping mechanisms, can effectively suppress pulsation.

6. Conclusion
Flow pulsation in pump heads under high-pressure conditions results from complex interactions between plunger motion, valve dynamics, and fuel compressibility. By combining CFD and experimental validation, this study provides new insights into the underlying mechanism. The findings suggest that targeted design optimization can reduce pulsation, enhance fuel injection stability, and extend the service life of high-pressure pump systems.