High Quality Delivery Valve 2 418 552 069 2418552069 Diesel Engine Spare Parts

1. Introduction and Background

Flow-induced noise generated by fuel delivery valves in diesel and gasoline injection systems has become a significant concern in modern engines, especially as industry demands quieter, more efficient, and higher-pressure fuel systems. When fuel flows through the delivery valve under rapidly changing pressures and transient opening/closing behaviors, complex turbulent structures, pressure pulsations, and cavitation may be produced. These unsteady flow phenomena can lead to flow-borne noise, structural vibration, and degradation of injection stability, ultimately influencing combustion performance and vehicle NVH (Noise, Vibration, Harshness) characteristics.
Therefore, a systematic investigation into the noise-generation mechanism and effective suppression methods is essential for optimizing fuel injection systems.

2. Research Objectives

This study aims to:

1. Clarify the flow-induced noise generation mechanism inside the delivery valve under high-pressure and transient operating conditions.

2. Establish a multi-domain coupling analysis model involving fluid dynamics, acoustics, and structural vibration.

3. Quantify the influence of valve geometry, lift profile, and flow conditions on noise amplitude and frequency characteristics.

4. Develop and validate effective noise-suppression strategies, including structural optimization, flow-path redesign, and damping measures.

3. Research Methodology

3.1 Multi-Physics Simulation

• Use CFD to simulate internal transient flow, turbulence, and cavitation behavior.

• Apply acoustic CFD and fluid-structure interaction (FSI) to analyze pressure pulsations and vibration transmission.

• Identify dominant noise sources using vortex structure analysis, pressure-wave tracking, and acoustic modal decomposition.

3.2 Experimental Measurements

• Conduct high-pressure bench tests to capture flow-induced noise using hydro-acoustic sensors and high-frequency pressure transducers.

• Measure structural vibration through accelerometers attached to the valve housing.

• Perform frequency-domain analysis to correlate test data with simulation results.

3.3 Evaluation of Suppression Strategies

• Modify valve seat angle, flow-path radius, damping holes, and lift dynamics.

• Introduce micro-groove flow-control features to stabilize turbulence.

• Validate noise-reduction effectiveness through comparative experiments.

4. Main Research Content

(1) Mechanism Analysis of Flow-Induced Noise

• Relationship between turbulence intensity and acoustic energy.

• Effect of cavitation bubble collapse on high-frequency noise.

• Influence of valve impact behavior and rebound dynamics.

• Identification of key frequencies associated with pressure-wave reflection in the high-pressure channel.

(2) Dynamic Modeling and Simulation Framework

• Development of a transient CFD-acoustic-FSI coupling model.

• Establishment of a mathematical model describing pressure pulsations and flow-path resonance.

• Comparison of simulation predictions with bench test data for validation.

(3) Noise-Sensitive Structural Parameters

• Valve seat curvature and flow contraction ratio.

• Valve lift speed and opening/closing symmetry.

• Fuel temperature, viscosity, and cavitation number.

• Housing stiffness and vibration transmission path.

(4) Noise-Reduction Strategies and Verification

• Structural optimization of the delivery valve to minimize turbulence generation.

• Application of damping structures to suppress resonance.

• Flow-channel redesign to reduce pressure-wave reflections.

• Experimental verification of noise reduction under multiple operating conditions.

5. Innovation and Contributions

• Proposes a comprehensive multi-physics coupling analysis method combining CFD, acoustics, and FSI for delivery valve noise analysis.

• Identifies key flow-induced noise sources and explains their mechanism through quantitative analysis.

• Develops optimized valve designs and flow-path control strategies achieving significant noise reduction.

• Provides technical guidance for next-generation low-noise fuel injection system development.