Thermal efficiency: how phase change improves cooling in power electronics
Did you know that phase-change cooling systems require significantly lower flow rates than conventional liquid cooling? This difference has a direct impact on energy efficiency, material reduction, and the reliability of power electronics equipment.
Why is phase change more efficient?
In a traditional cooling plate, the fluid (for example, water) is responsible for <>transferring heat from the component—such as an IGBT—to the point of dissipation.
The cooling capacity depends on the fluid flow rate and the increase in its temperature.
Q = m × Cp × ΔT
Q = amount of heat (calories)
m = mass of fluid (grams)
Cp = specific heat (in the case of water, 1 cal/g °C)
ΔT = temperature difference (degrees Celsius)
This means that to extract one calorie, it is necessary to raise the temperature of one gram of water by one degree Celsius, which implies large flow rates and high energy consumption in pumping.
The advantage of phase change: more heat evacuated with less flow
When a phase change is used (for example, from liquid to vapor), the process becomes much more efficient.
The same gram of water can extract up to 570 calories, taking advantage of the latent heat of vaporization (also called enthalpy of vaporization):
Q = m × hfg
hfg = latent heat of vaporization (in the case of water at 50 °C, 570 cal/g)
This means that phase-change refrigeration systems can transfer much more heat using minimal flow rates, reducing the size, complexity and energy consumption of the system.
Benefits of working with lower flow rates
Reducing the flow rate in phase-change-based cooling systems generates interesting technical and economic advantages:
Smaller diameter pipes
Lower flow rates allow the use of thinner conduits, reducing the total volume of the system and facilitating thermal integration in compact equipment.
Reduced erosion and corrosion
The low fluid velocity reduces erosion and corrosion in the cooling plate conduits, prolonging their service life.
Less coolant required
The thermal efficiency of the phase change makes it possible to use less fluid, reducing costs and minimizing environmental impact.
Conclusion: maximum efficiency with minimum complexity
The use of phase-change cooling systems allows power electronics equipment to achieve greater thermal efficiency with lower energy consumption and maintenance.
At ALAZ ARIMA, we design customized passive and phase-change cooling solutions, designed to optimize efficiency and reliability in sectors such as photovoltaic solar energy, wind power, and electric mobility.
👉 Discover our innovative solutions at www.alaz-arima.es/en/
Leave a Reply