Almost every industry involves the utilization of pipes, ducts and manifolds to handle wide range of fluids, gases or a mixture of solids and fluids. It is evident that these transport mediums are exposed to critical pressure and temperature, requiring thorough study on their designs to ensure longevity and performance.
A theoretical design calculation for these equipments only give information about the inlet and outlet conditions, and does not involve the details on the fluid flow behavior that is actually occurring inside the channels. Since the design of these components play important role in determining losses in desired output pressure, temperature or flow rate, it is essential to conduct comprehensive analysis of the system.
Computational fluid dynamics proves to be a decisive tool for such cases, providing detailed insights about important design considerations that can be incorporated prior to actual application.
Some common applications of CFD for pipes, ducts and manifolds are as discussed below:
Heat Transfer Studies:
For industries handling process streams at high temperatures using piping system, the prominent requirement is to avoid heat transfer losses that occur while the fluid is being transported. As such, the pipes are usually provided with insulating materials that prevent the motive stream heat from getting transferred to the atmosphere. The losses also occur due to complex bends in the piping arrangement, requiring the selection of suitable bend angles. While experimental investigation provides useful information, it is extremely difficult and time consuming to evaluate large piping systems. CFD as such is an alternative approach to assess the piping design comprehensively.
CFD provides insights on the convective heat transfer process occurring within the fluid flow, while also assessing the insulation capability of the material used on the pipes. Impact of bend angles and pipe materials on temperature loss can also be evaluated, which can be utilized as design inputs to perform required optimization for greater efficiency.
Pressure Drop and Vortex Studies:
Pressure drop is a crucial factor required to be studied in long range pipelines, HVAC ducts and exhaust manifolds. The accurate prediction of pressure drop helps in sizing the upstream and downstream equipments and also assists in optimizing the design. One of the prominent characteristics of fluid is the generation of vortex that leads to a choked flow and reduces the fluid pressure as well as cause the structure to vibrate. However, in many cases where sold and liquid mixing is required, vortex formation is equally important to ensure better mixing characteristics.
Utilizing the capabilities of CFD, the entire flow field can be studied to determine the impact of geometry and fluid flow parameters on pressure and vortex generation. Using turbulence model, CFD simulates the flow characteristics close to actual phenomena to better understand the flow and adopt necessary optimization techniques.
Industrial ducts such as chimneys, ash handling systems, etc. are required to handle fluids involving suspended solid particles. The design of these ducts requires understanding about the concentration of solid particles in liquids or gases to ensure that required pressure and temperature is maintained for successful evacuation.
CFD provides the facility to assess these systems by evaluating species distribution in fluids and its behavior inside the duct geometry. Through these simulations, parameters such as deposition, concentration, mixing ratio and flow velocity can be assessed for the designed duct geometry. Based on the results, the geometry or the fluid parameters can be optimized accordingly.
Mehul Patel specializes in handling CFD projects for Automobile, Aerospace, Oil and Gas and building HVAC sectors.