A small step for a man, a giant leap for the space industry and Econ Engineering: the Hungarian-founded and owned engineering firm Econ plays a significant role in the HUNOR (Hungarian to Orbit) program, which is shaping the future of Hungarian space research. The Econ team is developing a unique virtual simulation model that, by accurately modeling space conditions, contributes to increasing astronauts’ comfort and safety, greatly supporting the development of future space suits.
The goal of Econ Engineering’s project, named “Cincinnati,” is to adapt and further develop thermo-comfort simulation methods—already widely used on Earth—for the unique microgravity environment of space. The validation of this model will be supported by data from physical experiments conducted by the Axiom-4 research astronauts aboard the International Space Station (ISS). The project is led by Ákos Horváth, head of Econ’s Computational Fluid Dynamics (CFD) team, and László Kovács, head of Econ’s Research, Development and Innovation (RDI) group. Their research highlights that the special microgravity environment of space, where gravity is nearly absent, significantly affects human thermal comfort and heat perception compared to Earth’s gravity.
Everything is different in space – even sweating
Researchers at the European Space Agency (ESA) have found that during physical activity in space, the human body’s temperature rises faster and reaches higher levels than on Earth, and this elevated temperature persists even at rest. Thermoregulation changes significantly in microgravity. Microgravity greatly influences the behavior of the air layer trapped between the astronaut’s suit and skin. On Earth, natural convective currents cause warm air to rise because it is less dense than cold air, continuously ventilating the air around the body. In space, this convection is greatly reduced or practically absent, causing the heat emitted by the astronaut’s body to stagnate around them and between the suit and skin. This can affect comfort and even physiological or psychological well-being. Therefore, what astronauts wear in space matters greatly; space suits must be both safe and comfortable, as comfort influences work efficiency.
The aim of Econ’s research project
The “Cincinnati” experiment (Comfort Simulation of Space Suit Underwear via Draping and Heat Management Analysis), supported by the Hungarian Government’s HUNOR program, aims to develop a virtual simulation model capable of accurately replicating under-garment thermal comfort conditions in space. It will extend the thermo-comfort simulation methods widely used on Earth under normal gravity and validate them with experimental data collected by the Hungarian Axiom-4 research astronaut in space. This could open new horizons for improving astronauts’ comfort and safety.
The virtual model developed by Econ Engineering will enable detailed analysis during the design phase of how different clothing types—including the standard garments provided by the American space company Axiom Space for the Hungarian research astronaut—behave in space. The simulations will not only predict clothing wrinkling and fit during various movements but also the temperature and humidity distribution on the skin surface. Moreover, an integrated thermodynamic and fluid dynamic algorithm will simulate thermoregulation of the human body. Additionally, using finite element simulations (FEA), Econ’s engineers will consider how wrinkling and deformation of clothing in different body postures affect the thermodynamic state of trapped air under the garment and thus, thermal sensation. These factors are crucial for understanding astronaut comfort. The effect of clothing is modeled directly within the simulation rather than relying on empirical thermal parameters. Whether an astronaut performs a spacewalk or works only inside the ISS, the clothing requirements differ. Econ’s goal is to provide a general virtual simulation method applicable to any mission clothing, enabling reliable thermo-comfort assessment and supporting space suit development already at the prototype stage.
Why does simulation play a key role in the space industry?
Proper thermal comfort is important for everyone, but in industries like space, where specialized protective clothing must be worn, what a person wears is critical. Discomfort, such as sweating and skin irritation, can impair concentration and reduce work efficiency. On Earth, people can easily add or remove clothing layers as needed; in space, this is not an anytime or anywhere possibility. Therefore, astronauts need to have the best possible undergarments (in terms of textile type, stitching, cut, etc.) beneath their protective suits.
Simulation also plays a vital role in space suit development due to its efficiency and cost-effectiveness. Microgravity conditions cannot be replicated on Earth, so physical experiments are expensive, require lengthy preparation, and can only be performed in space itself.
Validation process of the simulation model
The validation and fine-tuning of the simulation models are supported by various terrestrial experiments to ensure they accurately reflect space conditions. Initially, Econ engineers conducted mechanical and thermal tests on the clothing materials using standardized equipment. The following steps have been or will be performed:
- In the first validation phase of the Cincinnati project, thermo-comfort measurements in space were preceded by terrestrial experiments using a so-called thermal manikin in a specialized climate chamber. Econ engineers conducted these tests over approximately two weeks.
- Subsequently, the astronaut’s clothing was tested and measured during ground-based experiments (Baseline Data Collection event), which also served as a dress rehearsal for the space experiment.
- The next phase will take place in space; the terrestrial simulation results will be compared with real experimental data collected aboard the ISS. During this phase, physical activity has to be performed to generate realistic body heat, providing an accurate picture of the thermo-comfort properties of various clothing under space conditions.
Thanks to this experiment, Econ’s new simulation model can significantly increase the level of virtualization in space suit development.
Econ’s terrestrial experimental measurements using a thermal manikin – Holger
There are various types and sizes of thermal manikins; in this case, a heated torso manikin (visible in the photos below) equipped with multiple temperature sensors was used. This allows the study of thermal comfort and heat regulation of virtually any clothing. The manikin wore the same clothing that, for example, a Hungarian astronaut will wear in space. In a specialized chamber, the engineering team created different thermal conditions and performed various measurements, determining the temperature at different points of the manikin’s body and the amount of heat released—essentially how the manikin “feels” at each point. The clothing was subjected to mechanical and thermal tests, examining properties such as strength, thermal conductivity and heat capacity, wrinkling, and others.
Using the thermal manikin, the external temperature distribution, heat transfer, and insulation efficiency of the clothing were measured, allowing analysis of how different temperature changes affect the human body, or in this case, the manikin simulating a human. The manikin can simulate human heat production, enabling the study of future space suits’ breathability and moisture management, which are critical for maintaining thermal comfort during spacewalks or other activities in microgravity.
Econ and the HUNOR program
The HUNOR (Hungarian to Orbit) program represents Hungary’s ambitious plan to send a Hungarian back to space after decades. As part of the program, Tibor Kapu, the Hungarian research astronaut as crew member of Axiom Mission 4 (Ax-4), launched aboard a SpaceX Dragon spacecraft on 25 June. After docking, he is expected to spend about two weeks aboard the International Space Station (ISS), conducting scientific experiments. The program holds significant scientific and economic potential, stimulating the development of Hungary’s space and technology sectors. HUNOR’s experiments cover many scientific fields, from biology and materials science to astronaut health monitoring.
Econ Engineering’s simulation research is an integral part of this program, contributing to optimizing astronauts’ living conditions.
Founded in 2002, Econ Engineering Ltd. is a Hungarian company offering a broad range of engineering services in simulation and simulation software, industrial automation, and composite materials. The company’s innovative approach and active participation in R&D projects led to its involvement in the HUNOR program and its role as an engineering supplier to Axiom Space in structural simulation. Econ is proud to contribute its expertise to both Hungarian and international space industry innovation and to the success of the HUNOR program, eagerly anticipating research results that could open new horizons in space suit design and manufacturing.
Econ is dedicated to promoting the innovative potential of Hungarian engineering knowledge, gaining international recognition, and providing support!
