Automotive life tips: the development of Portable Refrigerator for Car and the Principle of Air Compression

In recent years, as people’s desire for outdoor camping, off-roading, and exploration has grown, car fridge cooler have burst into our field of vision. Who wouldn’t want to camp in a wild ‘uninhabited area,’ such as a desert, grassland, or mountain, while enjoying fresh delicacies? Today’s car refrigerator technology is very mature; simply connect it to the cigarette lighter socket (some cars also have a portable refrigerator 12V port in the trunk or rear seat), and it can work continuously, whether for refrigeration or freezing.

The first real portable electric refrigerator, surprisingly yet sensibly, originated from spacecraft!

On April 12, 1961, humanity first entered space. His name was Gagarin, and during his inaugural space ‘business trip,’ he ate various meat sauces and chocolate sauces packed in containers similar to toothpaste tubes.

Later, when Americans went to space, astronaut John Young complained to NASA about the poor taste of space food, which was initially disregarded. In fact, astronauts’ meals had already begun to ‘evolve’ to consume compressed food. It wasn’t until NASA discovered that John had secretly brought a sandwich into space that they realized the importance of the issue and began to develop space food.

In 1982, Italian car refrigerator manufacturer Indel B became a strategic supplier for NASA. On June 27 of the same year, a specially developed Indel B refrigerator was launched into space aboard NASA’s Columbia spacecraft for space life, codenamed STS-4.

Since then, portable refrigerators have officially entered people’s lives. Below, we introduce the technological path and refrigeration principle of modern car refrigerators.

Car refrigerators can be divided into two categories based on their refrigeration technology.

The first category is semiconductor refrigeration car refrigerators.

Its principle relies on electronic chip cooling, using special semiconductor materials to form a P-N junction, creating a thermocouple that produces the Peltier effect, a new type of refrigeration method through direct current, with a cooling temperature range of -5 to 65 degrees Celsius. The advantages of this method include both cooling and heating capabilities, environmental friendliness, no pollution, small size, low cost, and operation without vibration, noise, and a long lifespan. However, its cooling efficiency is not high, and its capacity is relatively small.

The basic physical principle of semiconductor refrigeration technology:

When an electric current passes through a circuit composed of different conductors, in addition to producing irreversible Joule heat, there will be heat absorption and heat release phenomena at the junctions of different conductors depending on the direction of the current. If the current flows from the end A with a higher number of free electrons to the end B with fewer free electrons, the temperature at end B will rise; conversely, the temperature at end B will decrease. This was discovered by J.C.A. Peltier in 1834. Therefore, semiconductor car refrigerators have dual functions of heating and cooling, with a cooling range generally 20-25 degrees Celsius below ambient temperature, down to 5 degrees Celsius, and a heating temperature up to 65 degrees Celsius.

The second category is compressor refrigeration car refrigerators.

The compressor is the traditional refrigeration technology of conventional refrigerators, with a low cooling temperature of -18 to 10 degrees Celsius. It has high refrigeration efficiency, large volume, and is the mainstream direction for the future development of car refrigerators. The downside is that it is relatively heavy, has high energy consumption, and is more costly.

The portable gas refrigerator principle of compressor car refrigerators is through mechanical compression (compressor), convective heat exchange (condenser), and throttling and pressure reduction (capillary tube) to obtain liquid refrigerant. The liquid refrigerant evaporates into gas in the refrigerator body (evaporator), taking away the heat from the box through phase change, thereby achieving the refrigeration effect; finally, the gaseous refrigerant returns to the compressor; repeating the above process, the refrigeration system can continuously move the heat from inside the box to the outside, thus achieving the refrigeration effect. Therefore, the refrigeration principle of compressor car refrigerators is consistent with that of household refrigerators, with a cooling range that can reach as low as -18 degrees Celsius, and they do not have a heating function.

Of course, you can choose one portable refrigerator with battery for saving your car batter energy, so that the fridge can work longer. Whether in the countryside, on the beach, or traveling in mountainous plateaus, a mobile car refrigerator brings you not only frozen or fresh food but also an attitude towards life, the joy of living, and the composure and confidence to face life.

😊