Designing a custom tube Liquid Cold Plate requires careful consideration of thermal performance, mechanical integration, coolant flow, and manufacturing feasibility. Although embedded tube Cold Plates have a relatively straightforward construction, performance depends heavily on how tubing is arranged within the metal base.
What Is a Custom Tube Liquid Cold Plate?
A custom tube Liquid Cold Plate is manufactured to specific equipment dimensions and thermal requirements. It typically consists of an aluminum or copper base with embedded metal tubing. The tubing creates a coolant path while the base transfers heat from mounted components toward the circulating liquid.
1. Determine the Total Heat Load
Identify maximum heat dissipation and the locations of individual heat-generating components. For example, an industrial power electronics assembly may generate 1,500 W during operation. Maximum conditions, rather than average consumption alone, should guide design.
2. Estimate the Required Coolant Flow Rate
A preliminary flow estimate uses the energy balance equation Q = ṁ × Cp × ΔT, where Q is heat load (W), ṁ is mass flow (kg/s), Cp is coolant specific heat (J/(kg·K)), and ΔT is bulk coolant temperature rise (K).
For 1,500 W, water with Cp ≈ 4,180 J/(kg·K), and a 5°C temperature rise: ṁ = 1,500 / (4,180 × 5) ≈ 0.0718 kg/s, or approximately 4.3 L/min assuming water density near 1 kg/L.
This is an initial bulk-flow estimate, not a prediction of final component temperature. Interface resistance, heat spreading, inlet temperature, and channel-side heat transfer must also be assessed.
3. Optimize Copper Tube Routing
A serpentine layout can distribute coolant across multiple heat-source regions. However, longer tubes and additional bends can increase pressure drop.
Tube spacing and internal diameter
Minimum bending radius
Heat-source locations
Available plate area
Inlet and outlet positions
Coolant flow direction
4. Select the Base Material
Aluminum Base
Aluminum offers low density, good machinability, and relatively economical material cost, making it attractive for larger or weight-sensitive assemblies.
Copper Base
Copper provides higher thermal conductivity, potentially improving local heat spreading, but is heavier and generally more expensive. Selection must also consider cooling-loop material compatibility.
5. Control Tube-to-Base Thermal Contact
Heat must cross the interface between the base and embedded tube. Groove dimensions, tube geometry, fixing methods, and suitable thermal interface materials all influence thermal contact quality. Prototype testing is valuable for critical applications.
6. Consider Plate Thickness and Surface Flatness
Plate thickness affects rigidity, weight, and heat spreading. Mounting surfaces must meet the flatness and dimensional requirements of the electronic assembly. Mounting pressure and thermal interface materials should be considered together.
7. Evaluate Pressure Drop
Pressure drop depends on tube length, internal diameter, flow rate, coolant properties, and bend geometry. The cold plate must be assessed alongside the pump, fittings, and the complete coolant circuit.
8. Plan for Manufacturing and Inspection
Review tube bending feasibility, groove machining, assembly access, coolant connections, and finishing requirements. Inspection may include dimensional checks, leak testing, pressure testing, and flow verification.
What Information Should Be Provided to a Cold Plate Manufacturer?
2D drawings or 3D CAD models
Overall dimensions and heat-source positions
Maximum heat load and temperature limits
Coolant type and required flow rate
Operating pressure and pressure-drop limits
Port, fitting, and mounting specifications
Prototype and production quantities
Custom tube liquid cold plate design balances heat transfer, coolant flow, tube geometry, material selection, and manufacturing requirements. KINGKA offers custom tube liquid cold plate design and manufacturing based on customer drawings, including CNC-machined bases, embedded copper tubing, custom connections, and prototype support.
