The thermal challenge in space: how ARQUIMEA’s thermal control systems manage the extreme temperatures of SpainSat

The first of the two SpainSat New Generation satellites that will cover Spain’s governmental and military communication needs for the next 15 years was launched into space in the early hours of January 30th.

This is the most advanced satellite in Europe and one of the most advanced in the world, placing Spain at the forefront of technological innovation and security in the space sector. This program, led by Hispasat, is a milestone in Spain’s technological sovereignty and communications security, reinforcing the country’s strategic capabilities in the space sector.

The satellites will be deployed in geostationary orbit and will operate in various bands, including X-band, military Ka-band and UHF.

ARQUIMEA has been in charge of the co-engineering, detailed design, manufacturing and thermal hardware integration support for the new SpainSat satellites.

What is SpainSat NG?

The SpainSat NG program consists of launching two satellites into space and its operation that will provide real-time communications without interference and with extreme security thanks to state-of-the-art systems and technology.

The satellite operator company Hisdesat has count with thirteen Spanish companies to develop and manufacture this large-scale project, such as Airbus, Thales Alenia Space and Indra.

The coverage of these satellites will cover an extensive global area, ranging from the United States and South America to the Middle East, including Africa and Europe, and reaching as far as Singapore on the Asian continent. They incorporate advanced anti-jamming and anti-spoofing technologies, and will be reinforced and protected against nuclear phenomena at high altitude.

ARQUIMEA’s role in SpainSat NG

In ARQUIMEA we have been in charge of the thermal systems on board the satellite. These are of vital importance for the correct functioning of the equipment and components on board, ensuring that they operate within the appropriate temperature ranges in the demanding conditions of space.

Arquimea has also provided microelectronics (“chips”) that are incorporated into the electronics of the new X-band antennas.

The extreme conditions of space

Space is a hostile environment where temperatures vary extremely. In a vacuum, with no atmosphere to regulate the heat, objects exposed directly to the sun can reach temperatures of more than 120º, while in the shade they can drop to -270º, close to absolute zero.

These conditions pose a great challenge for space technology, since satellites and spacecraft must have advanced thermal systems that regulate their temperature and ensure their correct operation in any situation.

In addition, satellites are made up of systems and payloads, which also generate large amounts of heat and must have a controlled temperature for their correct operation.

In the case of SpainSat, the thermal system has also had to be adapted to the specific needs of the program, since the X- band antennas generate a large amount of heat that needs to be dissipated for it to work properly.

And now that we know all the challenges posed by space, how are all these temperature problems solved? With Heat Pipes (HPs) and Loop Heat Pipes (LHPs).

The key to the operation of the active antennas on board the satellite.

The thermal system consists of arrays of HPs and LHPs, which allow high power levels to be extracted from the active antennas. In essence, they are heat dissipation mechanisms.

• Heat pipes are passive heat transfer devices that combine the principles of capillary pumping and evaporation-condensation of a fluid (dual phase) to efficiently transport heat between two solid interfaces. Capillary pumping occurs in internal slots that have these elements.
• Loop heat pipes are a two-phase flow (liquid-vapor) heat transfer device that uses the evaporation and condensation of a working fluid to transfer heat. In addition, capillary forces developed in the fine porous wicks present inside these devices in the evaporation zone circulate the fluid. This type of equipment is often used in situations where heat pipes would be ineffective, such as cases where mechanical decoupling is required (for example, deployable radiators). Also, loop heat pipes are less sensitive to operating in gravity than heat pipes, facilitating the execution of several tests.

In the case of Spainsat NG, all the heat generated by the X-band antennas is collected and transported by the HPs and LHPs to the main radiators of the satellite, where it is evacuated into space.

The design and definition of the thermal system has been particularly complex in this project due to the small volume available and the complexity of the interfaces with the electronics, the demanding operating levels and mass limitations.

 

Benefits and experience of Arquimea’s thermal systems

At ARQUIMEA we have been designing, manufacturing, integrating and testing thermal systems for more than 20 years. In the case of SpainSat, the HPs and LHPs have to withstand great quantities of power, which is a technical challenge, due to the fact that in space there is no air to help us manage the temperature and dissipate the heat.

“In space, managing all the heat and power from satellites and their payloads is a major challenge due to the lack of air. Managing the right amount of heat dissipation in space and having the systems at the right temperature for proper operation is critical. We perform the entire design, manufacturing and testing process in-house to ensure all elements of the thermal system are working perfectly.” – José Luis Pastor, Senior Thermal Engineering

Our experience in this field has enabled us to develop advanced solutions that guarantee efficient and reliable thermal control, even on missions as demanding as SpainSat. As a result, we contribute to the operability and safety of satellites in space.

The future of the space sector

Our participation in the SpainSat NG program reinforces our position as leaders in the development of thermal solutions for the space sector. In ARQUIMEA we continue demonstrating our capacity to face highly complex technological challenges, contributing to strategic missions of great impact. This project consolidates us as a reference in the aerospace industry and underlines our commitment with innovation and technological sovereignty in the space field.

Other projects in which we are making a significant contribution to their development are:

• Artemis: NASA’s flagship program in which it will return humans to the moon. It will be NASA’s first manned mission that will aim to establish a long-term presence on the Moon for science and exploration. Launch is scheduled for September 2025 at the earliest.
• Beetlesat: The LEO satellite constellation providing global Ka-band connectivity for secure point-to-point communications, cellular backhaul, mobility and additional premium services in the commercial and government sectors.

Thermal control systems are critical to ensure the optimal performance of satellites in space. Thanks to our experience and technological know-how in the design and manufacture of these systems and their structures, we manage each project in a comprehensive manner. From the design and prototype development phase to manufacturing, testing and final integration, we ensure efficient solutions adapted to the most demanding environments.