Subsea Pressure Equalization via Accumulator and Nozzle
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for pressure equalization in subsea equipment, such as repeatedly opening and closing valves, lead to instantaneous and unpredictable pressure changes, causing equipment damage and valve malfunction due to frequent operations and high pressure differences.
Innovation Solution
A system comprising a fluid inlet, outlet, flow line, accumulator, and flow restricting nozzle, which allows for controlled pressure equalization between high and low-pressure fluid conducting pipes by matching pressures through the accumulator and nozzle, reducing the need for repeated valve operations and minimizing abrupt pressure changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If valves are repeatedly opened and closed for pressure equalization, then pressure can be equalized between high and low pressure sides, but valve lifespan decreases due to frequent operations and leakage risk increases
Solution Approach 1:
A small volume chamber is introduced as an intermediary between the two valves. This chamber acts as a buffer that accumulates pressure changes, allowing the valves to operate fewer times while still achieving pressure equalization between the high and low pressure sides.
Solution Approach 2:
The system pre-positions a small volume chamber between the valves to prepare for pressure equalization. This chamber is designed to handle the pressure transitions, so when valves need to operate, the pressure changes are already buffered, reducing the mechanical stress on the valves themselves.
2Stress or pressure
If traditional nozzle designs are used to slow down pressure change, then pressure change rate can be reduced, but flow behavior becomes unpredictable due to cavitation and high velocities
Solution Approach 1:
The nozzle is specifically designed with parameters (dimensions, geometry) optimized for low Reynolds number flow conditions. This ensures that as pressure changes occur, the flow remains in the laminar zone where behavior is predictable, avoiding cavitation and turbulence that would make flow characteristics uncertain.
Solution Approach 2:
The patent references and applies principles from established low Reynolds number nozzle designs (such as those described in WO 2010/080037 A1), copying proven geometric configurations that have been demonstrated to provide stable, predictable flow behavior under pressure equalization conditions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system provides a smooth and predictable pressure transition, extending valve lifespan and preventing equipment damage by controlling pressure changes, thus ensuring reliable operation in subsea environments.
Implementation Method 1
an accumulator or other pressure storage reservoir in fluid communication with the fluid flow line and configured to store and release fluid from the fluid flow line
Implementation Method 2
a flow restricting nozzle positioned between the fluid inlet and fluid outlet
Implementation Method 3
In the case of a liquid, if close to its boiling point, will start evaporating to gas when the pressure starts dropping, thereby indirectly acting as an accumulator
Data Source
AI summary
Systems and methods for controlled equalization of fluid pressure are described. The system can include a flow restricting nozzle in line with an accumulator which together provide a gradual, controlled equalization of pressure between two locations. For example, in the subsea environment, the pressures can vary between a subsea processing station and a subsea flow line. The systems can be configured as ROV retrievable, or they can be integrated into the subsea processing station. In some cases, more than one accumulator and/or more than one flow restricting nozzles can be used in the system to provide for versatility and robustness.