◎ Science and Technology Daily reporter Wang Yanbin
In the meantime, there are still more than half a month to go, and the three astronauts of Shenzhou 13 are about to successfully complete their tasks and return to the ground. For Li Gong, he is not only looking forward to the triumph of the "space heroes", but also paying attention to their diet in space.
Li Gong's identity is the deputy chief designer of the space kitchen project department of Jiuyang Co., Ltd. (hereinafter referred to as Jiuyang). He and his colleagues either led or participated in the development of four sets of technologies into the "Heavenly Palace" to provide life support for astronauts.
The Jiuyang Space Kitchen project team is developing "space soy milk". Courtesy of the Jiuyang Space Kitchen project team
These four sets of technologies are hot air heating device, drinking water dispenser, "space soybean milk", and intelligent IoT control App. In the "Tiangong", the hot air heating device is used to heat space food and make yogurt, the drinking water dispenser is used to filter out the silver-containing raw water and ration the drinking water of astronauts, the smart App is used to control all the kitchen products of the space station, and the "space soy milk" can be drunk in the space environment.
Astronaut Wang Yaping is introducing the space kitchen.
Astronauts work very hard in space, and dietary conditions directly affect their mental and physical state. But for them, eating and drinking well in space is not easy.
Eating well and drinking well in space is not easy
From the appearance, the "space soybean milk" obtained by the Science and Technology Daily reporter is more like a bag of fully sealed vegetable and fruit puree, but unlike the ordinary soybean milk directly formed after "directly adding water to polish with soybeans", "space soybean milk" does not need to be crushed, it is produced on the ground, directly brewed in space, and this soybean milk powder is desegsed; at the same time, this soybean milk powder is directly flushed with the moderate temperature clean water flowing from the water dispenser, and there is no heating problem.
Behind the launch of "space soy milk", researchers have achieved a three-in-one combination of "wall breaking level 2, aerospace food chemical pollution requirements and sensory evaluation A level" to ensure its safe, nutritious and tasted space quality, and thus obtained a national invention patent.
Drinking soy milk in the space environment, the water temperature control should be precise, and the water speed control should be more stable. It is understood that blisters are easy to occur in the water flow in the weightless environment, and it is necessary to accurately control the water speed to ensure that the water is uniform and avoid the formation of bubbles.
Jiuyang engineers told reporters that in the space station, the astronauts' drinking water and eating are not only affected by the space environment, but also to avoid microbial pollution.
According to the study, 84 kinds of microorganisms have been found on the International Space Station, and there are various sources, including microorganisms carried by the occupants themselves, materials and equipment carried by the space station, introduced during the ground assembly testing phase and the launch preparation stage, and carried by visiting spacecraft and their cargo. These mean that almost all space kitchens use antimicrobial materials.
The "four-needle zinc oxide whisker" aerospace antibacterial material has a unique three-dimensional four-needle three-dimensional structure, which is evenly distributed in a variety of matrix materials such as plastic, rubber, painted activated carbon, giving the material unique antibacterial functional characteristics.
The project "Development and Promotion and Application of Antibacterial Materials in the Cabin of Manned Spacecraft" led by the Functional Polymer Materials Team of Southwest Jiaotong University won the first prize of the Sichuan Science and Technology Progress Award in 2020. The project was led by Southwest Jiaotong University, and the antibacterial materials for manned spaceflight in which Jiuyang participated were applied to the space kitchen.
Li Gong gave an example: "In the space station, the total number of colonies after daily drinking water purification is very strict, almost 0, stricter than the 100cfu/ml required by the domestic drinking water standard. ”
Space Kitchen is China's original, but also "unique"
Shredded fish, diced kung pao chicken, assorted fried rice, curry fried rice, mushroom chicken nuggets, shredded snow vegetables, black pepper beef fillet, braised pork, winter bamboo shoot ham fried rice... These delicacies appeared in the "Heavenly Palace".
The key question is how to heat it? Why is it more difficult to heat evenly in space than on the ground?
According to reports, compared with the ground, the floating of food in the weightless state will affect the uniform heating of food; at the same time, space heating needs to be packaged, and the challenge is the thermal barrier of food packaging materials with packaging and the heat uniformity of food.
"Compared to the ground, the floating of food in weightlessness affects the uniform heating of food." Li Gong introduced that around the characteristics of space food and the weightless environment of space, they proposed a new design concept of hot air heating device, and used methods and tools such as mathematical modeling, mechanics and fluid simulation to continuously optimize the design, and finally completed the design and finalization of the hot air heating device.
This hot air heating device is used to heat aerospace food and make yogurt, so that food can be fixed in the heating plate rather than "floating" in mid-air, not only heating more types of food and heating evenly, can meet the aluminum foil packaging, metal cans, plastic packaging and other packaging methods of heating, perfectly solve the compatibility of food packaging and heating uniformity, so that more Chinese food can enter space.
"Recently, the China Astronaut Scientific Research and Training Center sent a "thank you letter" to Jiuyang, and the astronauts gave feedback that the relevant equipment developed by Jiuyang had a good experience in on-orbit application, which made us feel encouraged and proud." Han Run, vice chairman of Jiuyang, told reporters: "We have successfully solved the problems of diet processing and drinking water purification in the extremely harsh outer space environment such as 'vacuum, weightlessness and no convection' through independent innovation technology, and achieved a high level of scientific and technological self-reliance and self-improvement." ”
The reporter learned that as one of the earliest enterprises to participate in the development of the national manned space engineering project, Jiuyang undertook the development task of the space kitchen project as early as 2014. Han Run emphasized: "The intelligent space kitchen is an original in China and has reached the international advanced level. ”
It is reported that the above products have been converted into civilian use and entered the market.
Source: Science and Technology Daily
Editor: Wang Yu
Review: Yue Liang
Final Judgement: Wang Yu