Better Valve Design and Increased ROI with Simulation
Valves are important elements in a variety of applications, particularly those related to consumer needs of water, gas or other utility agent flow control. However, the most important applications of valves are industrial — specifically, applications associated with mining, oil and gas extraction, processing and distribution, water circulation, power generation, chemical, manufacturing or food processing.
Given their wide range of applications, designers and engineers need to optimize the valve design and make sure they properly test it in different conditions. One of the key technologies used to create a better valve design is engineering simulation and in this article, I will focus on explaining why.
Role of Simulation in Creating a Better Valve Design
The valves industry requires continuous design and manufacturing process improvement. The industrial revolution — which is driven by constant advancements in digital technologies — is not only generating innovative products but also better processes, product customization, faster access to market, cost reduction, and general efficiency improvement by accelerated return on investment (ROI).
Modern manufacturing processes are based on the same digital model of a valve, used in all fabrication workflows, from engineering concept and design to testing laboratories and engineering validation, production, marketing, and sales. The global demand for industrial valves is projected to grow by 5.4% average rate in the next five years, and the market value expected to surpass $70 billion by 2019. The increasing demand for oil, gas, chemical, and utility applications is expected to be one of the principal drivers for the industrial valves market development. 
This industry is one where engineering and design should be in close cooperation. The market’s growing appetite for innovative formats and functionalities has driven the creation of dedicated CAE/Computer-aided engineering or CAD/Computer-aided design solutions that enable cost-effective and time-efficient design improvements to be tested through real-time simulation iterations.
Using a traditional manufacturing process, it could take a few weeks to create a new valve model. Using engineering simulation, the time needed for the same model can be dramatically shortened— sometimes to just one day.
Any optimization process should be based on a complex set of analyses, including structural, flow, and thermal behavior. Each of these simulation methods and their results gives crucial insights to ensure a better valve design, replacing or reducing physical testing and the associated costs.
The key reasons why simulation is now widely used in the industry are:
• Interactive models could forecast potential new changes in design layout, which are vital for improving the valves’ performance
• Simulation models offer precise and detailed information about valves’ design parameters, material structure, and thermal behavior
• Simulation saves time and cost by eliminating the need for physical prototypes.
Due to the large applicability, the simulation models for valves are used in many vertical industries for varying analytical capabilities such as aerospace, automotive, HVAC, petrochemicals, power generation, manufacturing, oil and gas process engineering, and turbomachinery.
Different Valve Type and Suggested Simulations
The purpose of a simulation is to help engineers create a better valve design, through performance optimization, investigating flow or material behavior, reduce pressure drop, and more. Here is a summary of the main valve types and the functional particularities to be considered in the design process:
• Globe valve – mainly used for regulation flow, comes with main advantages of a balancing feature which reduces the required actuator forces. Computational Fluid Dynamics (CFD) and structural analyses are mostly recommended.
• Butterfly valve – based on a rotating vane, it is a high-pressure recovery valve used in applications where high-capacity, fast velocity, and relative high-pressure are required. Starting from this, a powerful combination between Computational Fluid Dynamics (CFD) and structural analysis are recommended.
• Ball valve – the ball control based on a rotating system. It is a high-pressure recovery type of valve, in which the flow of fluid is restricted by using a full or partial type ball in the valve body. A powerful combination of solid standard FEA and Computational Fluid Dynamics analysis is recommended.
• Gate valve – typically designed for high-pressure and temperature-motive fluids. Structural, Computational Fluid Dynamics (CFD), and thermal analyses are recommended.
• Diaphragm valve – controls flow by a movement of a diaphragm. Upstream pressure, downstream pressure, or an external pneumatic or hydraulic source can be used to change the position of the diaphragm. Pressure analyses for diaphragm and CFD are recommended.
• Flow Control Valves (FCV) – typically used in many applications involving high-pressure and fuel control, such as spatial transportation vehicles, request critical structural, CFD, thermal and acoustic analyses.
• Three-way valve – primarily used for a splitting or mixing service. The most common applications are related to heat transfer control or in the controlled mixing of two streams. Recommended analyses are structural, CFD, and thermal.
• Thermal expansion valve – used in refrigeration and air conditioning systems. CFD and thermal analyses are recommended.
Regardless of the applicability and model type, the valves are generally designed for high temperature and fluids that could impact their structural strength, due to excessive stress generation and concentration in restrictive regions. The most confident way to establish a reliable structural behavior is to perform a stress analysis based on the finite element method (FEM).
A stress analysis primarily investigates the stress state of the valve body and considers various loading conditions. The analysis is mostly focused on the body material nonlinearity considering elastic-plastic behavior. The valves’ connections with the various pipeline or recipient interfaces should also be key points of consideration.
Based on numerical methods to solve the fundamental nonlinear differential equations that describe fluid flow for predefined geometries and boundary conditions, CFD software facilitates the structural optimization of valves in the design of hydraulic components.
The CFD simulation process suggests a range of models for flow velocity, density, low-pressure zones around the corners, impingement angles for wear studies, minimum temperature behavior or chemical concentrations for any region where flow occurs.
Continuous improvement in CFD mathematical models and the increase in the speed and capacity of workstations has made the implementation of newest CFD modeling and the production of simulations for full 3D flow dynamics possible, contributing to the process of creating a better valve design.
For many industries where the valves are controlling the high temperature of the fluids, there is a possibility that the components will deform under such high thermal stresses and develop cracks in the assembly, leading the valve to fail prematurely.
Particularly, high-temperature valves  are designed to deal with the effects of thermal expansion and the loss of body material strength at elevated temperatures. In many cases, high-temperature valves must also deal with the issue of thermal shock. The rate at which any valve component heats up is dependent on the local heat transfer coefficient and the local temperature difference between component and the steam.
The main simulation variables are related to local steam velocity across the component surface and the thermal boundary layer. Thermal simulation for valve designs is based on a common method using finite element analysis (FEA) to conduct a transient thermal analysis.
Why Valve Design Simulation with SimScale?
The most important advantage created by SimScale for a better valve design optimization is that the user has the same web-based environment for individual or multiple simulation methods, integrating structural mechanics, fluid dynamics, and thermodynamics simulation.
Using the SimScale simulation platform, designers could seamlessly validate experimental results, run parametric studies, and mix different simulations methods. Valve designs could be optimized to reduce pressure drops, homogenize flow, or to improve laminar and turbulent mixing.
Additionally, the SimScale Public Projects Library has thousands of projects ready to be used for free as templates, to help you create a better valve design with engineering simulation, in the shortest time possible.
1. “Industrial Valves Market by Type, by Application, and by Region”- Global Trends & Forecasts to 2019, Research and Markets, May 2015
2. “Process Design of Valves” – KLM Technology Group Project Engineering Standard, April 2011
3. “Water Flow through Globe Valve” – David Heiny, SimScale Public Projects, 2015