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A pressure regulating valve is a type of flow control device that is a combination of a control orifice and a flow compensator. The compensator orifice modulates its opening to regulate the flow rate at a constant pressure drop across the control orifice. The objective of this paper is an experimental and numerical analysis of flow compensation forces on pressure regulating valve applied on aircraft engine and control systems in a Fuel Metering Unit (FMU). The CFD analysis was applied to analyze and evaluate the various flow rates and patterns and thus estimate the pressure regulating control valve flow compensation force and characteristic curve. The CFD model is used to validate the dynamic behavior of the pressure regulating valve to bypass the fuel flow from a high pressure gear pump and to compensate burn flow of the metering valve. The model can then be used to evaluate and improve the design and operation of the valve for specific operations.

Tilting pad bearings are designed by hydrodynamic principles and have been utilized in applications carrying shaft thrust or radial loads in many mechanisms for decades. The object of this paper is to derive the optimized pivoting positions in the radial and circumferential directions of tilting pad thrust and radial bearings and to calculate minimum fuel film thickness for a given running condition of velocity, temperature, viscosity, bearing geometry, and loading forces. The Reynolds equation derived on the tilting pad bearing fluid model is simplified into a one dimensional equation and applied in two dimensions to solve for the minimum fluid film thickness from pressure distribution in the load-carrying analysis.