Piezoelectric Micropumps: The Power Behind Next-Generation Micro Liquid Cooling

1.Introduction
2.Requirements
3.Applications
4.Solutions
5.Future

Introduction
The electronics industry is experiencing a thermal problem. AI, 5G and high-performance computing mean continued overpowering. Modern processors have billions of transistors in very small packages. Data centers and edge devices put more computing power in cramped spaces. So consumer electronics require high performance without excessive measures in super thin designs. Traditional air cooling can not meet these demands anymore. When devices must be thinner and more compact in size, it affects the airflow. Heat can not be removed fast enough and performance is reduced because of thermal throttling.
The benefit of liquid cooling is quite obvious. Liquids have better heat transfer performance than air. However, traditional liquid cooling systems are based on bulky electromagnetic pumps, thick tubing and large heat exchangers. These systems are to be used for servers and industrial equipment. They cannot be incorporated into thin devices. Micro liquid cooling changes this situation. By shrinking all the components of the cooling loop, the use of liquid cooling becomes possible with small products and thin products. It is the piezoelectric micropump that is the key enabling component.
With long-term experience in piezoelectric technology, Bestar makes compact, efficient and reliable micro liquid cooling solutions. Our piezoelectric micropumps excactly are the driving force which makes micro liquid cooling practical.

Requirements
Microliquidcooling makes severe demands on the pump technology. These requirements must be fulfilled simultaneously: compact size, sufficient pressure and low power consumption. Piezoelectric micropumps fit the bill on all.
1. Compactness
Electromagnetic pumps use motors, coils and rotating impellers. These components have large volume requirements. Even the smallest designs are several centimeters thick. Piezoelectric micropumps are motors-free and rotating parts-free. By using piezoelectric ceramic elements which get deformed when a voltage is applied to them. This deformation causes the flow of fluid to move through micro-scale chambers and valves. The resulting pump profile is few millimeters thick. This makes it suitable for use in smart phones, tablets, wearables and other super-thin devices.
2. Pressure
Micro liquid cooling systems make use of narrow micro-channels in order to enhance heat transfer efficiency. These channels result in high flow resistance. To force the coolant to circulate adequately, high pressure is required to keep it circulating. Piezoelectric micropumps have high frequencies. Rapid vibration creates pulses of pressure which efficiently pump fluid through high resistance microchannels. This guarantees consistent flow and guaranteed heat removal, even in the very complex cooling circuits.
3.Efficiency
So power consumption is critical in compact and battery-powered devices. Piezoelectric micropumps are in the milliwatt power range. This keeps the energy loss to a minimum and increases battery life. There is no mechanical noise and vibration. Cooling is entirely non-obtrusive to the user. Reliability is also another significant plus point. Piezoelectric micropumps have simple mechanical structures. There is no bearings or brushes to wear out. This allows for long service life along with performance which remains stable over 10000 of service.

Applications
Consumer Electronics
High-end smartphones and gaming devices produce a lot of heat when loaded for a prolonged period of time. Micro liquid cooling makes it possible to obtain stable high performance without thermal throttling. Ultra-thin laptops also enjoy more thermal supply room in small designs.
Wearables and AR/VR
There are devices that are closeolerance method, such as near-eye devices which have heat sources close to the user's face. Precise thermal control for better comfort with protecting optical components. Piezoelectric micropump based cooling allows longer time usage and higher processing power.
Medical Devices
Portable diagnostic equipment needs a precise temperature control. Microliquid cooling is guaranteed to ensure stable operation in compact systems that run off battery power. Piezoelectric micropumps also are used for precise fluid delivery in drug administration devices.
Automotive Electronics
Autonomous driving systems are based on sensors and processors that operate in harsh environments. Micro liquid cooling helps in providing dependable thermal management for confined sensor housings. Silent working and high reliability refers to automobile grade.

Solutions
Bestar offers more than single components but a solution. We can provide fully complete microliquid cooling solutions based on customer applications. Each component of microliquid cooling system is designed to work as one thermal management system. This strategy places a certain demand on high efficiency, small size and high reliability for long time periods.
Bestar has a flexible ability to custom design to meet specific designs. We work closely with customer engineering groups obtaining an understanding of the system space, thermal loads and system architecture. Depending on such inputs, we tailor pump parameters as well as flow rates and pressure characteristics and mounting interfaces. We also have ability to facilitate coolant selection and optimization of fluid circuits. 

Future
Thermal Management has started being the electronic design limiting factor as devices become smaller and smaller, and power density rises, conventional cooling methods will not work. Piezoelectric micropump based micro liquid cooling is an alternative to thermal design. It allows to provide high performance without sacrificing size, noise or power efficiency.
The future of electronics is reliant on good cooling. Micro liquid cooling using piezoelectric micropumps eliminates thermal barriers and allows the next generation of compact and high performance devices.
We hope you will be in touch with Bestar to discover new and advanced thermal management solutions to define new standards for cooling in the age of miniaturization.