(a) Describe, with the aid of a sketch, the construction of a plate type heat exchanger.(7)
(b) State THREE advantages of the plate types, compared with the tube type heat exchanger.(3)
Layout of a Plate Type Heat Exchanger
Main Components and Their Location
A plate type heat exchanger typically consists of the following components:
- Plates: These are the core components, arranged in a stack. They are corrugated to enhance heat transfer and fluid mixing. 1. Modeling and Design of Plate Heat Exchanger – IntechOpen www.intechopen.com2. Schematic of the heat exchanger and corrugated plate. – ResearchGate www.researchgate.net
- Frame: This is the outer structure that holds the plates together. It provides support and rigidity to the heat exchanger. 1. Plate heat exchanger – Wikipedia en.wikipedia.org
- Gaskets: Placed between the plates to prevent fluid leakage and direct the flow. 1. How does a plate heat exchanger work – Alfa Laval www.alfalaval.sg
- Distribution and Collection Manifolds: These are channels that distribute and collect the fluids to and from the plates. They are located at the inlet and outlet of the heat exchanger.
- Tie Rods or Bolts: These hold the plates and frame together under pressure.
- Fixed Plate: This is the base plate of the heat exchanger, often with inlet and outlet connections. 1. Plate Heat Exchanger (PHE) Explained – saVRee savree.com
- Pressure Plate: This is the top plate that applies pressure to the entire stack.
Typical Layout
- The plates are stacked alternately to create flow channels for the two fluids. 1. Modeling and Design of Plate Heat Exchanger – IntechOpen www.intechopen.com
- Gaskets are placed between each plate to seal the flow channels. 1. How gasketed plate heat exchangers work – Alfa Laval www.alfalaval.com
- The distribution and collection manifolds are located at the ends of the plate pack.
- The frame encloses the entire assembly, providing support and rigidity.
- Tie rods or bolts are used to clamp the plates together and compress the gaskets.
Visual representation:
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plate heat exchanger layout
Advantages of Plate Heat Exchangers Compared to Tube Heat Exchangers
Plate heat exchangers offer several advantages over their tube-and-shell counterparts:
Efficiency
- Higher heat transfer coefficient: The large surface area and turbulent flow provided by the corrugated plates result in significantly better heat transfer.
- Lower pressure drop: Reduced resistance to fluid flow leads to lower energy consumption. 1. 7 Advantages of Plate and Frame Heat Exchanger Over Shell and Tube www.csidesigns.com
Compactness
- Smaller footprint: Plate heat exchangers are generally more compact than tube-and-shell units for a given heat transfer capacity. 1. 5 Reasons to use plate-and-frame heat exchangers instead of shell-and-tube – Alfa Laval www.alfalaval.com
Flexibility
- Easy cleaning and maintenance: Plates can be easily removed and cleaned or replaced. 1. Plate Heat Exchanger (For Dummies) – Rasmussen Mechanical Services www.rasmech.com
- Capacity adjustment: The heat transfer capacity can be adjusted by adding or removing plates. 1. How does a plate heat exchanger work – Alfa Laval www.alfalaval.sg
Cost-effective
- Lower material usage: Generally require less material compared to tube-and-shell exchangers.
- Lower installation costs: Due to their compact size and easier installation.
Other advantages
- Lower fouling: The turbulent flow helps to reduce fouling on the heat transfer surfaces. 1. 8.6 Fouling – SWEP www.swep.net
- Versatility: Can handle a wide range of fluids and operating conditions. 1. Plate Heat Exchangers | AxFlow www.axflow.com
While tube-and-shell heat exchangers are still used in many applications, plate heat exchangers have become the preferred choice for many due to their superior performance and efficiency.