Thermal drum or bag refrigerator difference

Test of nine bags-colds: theory of heat exchange

Even a person far from physics knows very well: to heat something is much easier than cooling. A person has learned to make fire for a long time, but for millennia for millennia for millennia. And all because heating is essentially similar to chaos, but cooling is akin to cleaning. And cleaning and repairing is much more difficult than to litter and break. We will check this postulate as part of our test of nine bags-colds.

For the next test, we have chosen relatively inexpensive one times in the days of the cooler bags that are designed to maintain a microclimate on the road. Of course, 2400 is not cheap at all, but we took such bags, as they say, for comparison. Otherwise how to evaluate the difference between cheap and expensive?

It is clear that such bags do not know how to cool anything: their task is to prevent the heat exchange of products stored in them with the external environment. The thicker the walls and more tight of the fastener, the slower the contents will be more slow. Of course, if you have purchased a bottle of juice were warm, then it will remain even in the most expensive bag-cooler. The so.called cold accumulators can correct the situation. plastic containers with all kinds of fillers. Such a box should first be frozen in a household refrigerator, and then placed along with products that they intend to take on the road. The place will have to sacrifice, but art requires victims. It is also extremely desirable to put the products by chilled.

Speaking of cooling. There are a number of simple rules that allow the use of cooler bags with the maximum possible benefit. For example, one liter bottle is better than two half.liter, since the smaller the surface, the less and heat transfer! For the same reason, a large bag, generally speaking, is worse than a small! It will justify itself only when it is clogged under the eyeballs. When traveling, the cooler bag should be kept in the cool place: in the trunk of the sedan it will be very bad for her. Finally, the more often you climb into such a bag behind drinks and chocolate, the faster all its contents will heat up.

What to look for when choosing a cooler bag

Varieties. There are two types: thermal drums and thermal containers. Thermal drums are distinguished by the conservation time of the desired temperature regime, volume and, accordingly, dimensions. Colder bags are mobile and more convenient in transportation, and containers are more suitable for transportation in vehicles, but contain a significant number of products, while holding longer.

• Weight and volume. The more these parameters, the more difficult it is to move the Kholodnik bag yourself. Decide how thermal drum will be delivered to the destination. For hand luggage, models up to 30 liters are suitable, and for a car from 40 liters and above.
• External manufacturing material. Choose a cooler bag made of impact-resistant plastic, and in the case of a cooler bag-from synthetic durable fabric having water-repellent properties. It can be polyester, polyvinyl chloride, nylon, etc. D. Such types of fabrics are easy to clean and dry quickly.
• Internal manufacturing material. Some companies save, making the inner layer not of high.quality materials with reflective properties, but from ordinary polyethylene. If the thermal drum is made using the same PVC, then the products in it will remain fresh for 12 hours, and when the cold accumulators are equipped for 24 hours. If polyethylene was used, then storage time will be reduced to 2-3 hours.
• Wall thickness. Take an isothermal bag before buying. If the walls are thin and a layer of thermal insulation is not felt, then the product will not be able to provide prolonged cooling. Ideally, the thickness of the polyurethane foam located between the walls should be at least 3-5 cm.
• Pens, shoulder straps, rollers. With a small volume of the choller bag, it is easy to transfer it in the hands or on the shoulder. For this, the product is equipped with comfortable handles or a strap with a soft substrate. In the case of a large volume, the models are equipped with rows of rollers for light rolling and telescopic (retractable) handle, which we are used to seeing, for example, in suitcases.
• Locks. They are built up to protect the contents from raids of dogs, cats and other animals. Most often, locks are located in the handles of the product. When choosing, check if they are closed reliably.
• Cold batteries. The presence of 4-5 batteries for an isothermal bag of medium size is considered optimal. This amount allows you to place them in the lid and walls. Do not forget that the larger the volume of the cooler bag, the more batteries will be required.

Rating of the best cold batteries for thermal

To understand what kind of cold battery for bags the Kholodilnik is better to buy, you need to study popular models. Several products are in greatest demand.

Thermos

The cold battery is supplied in a firmly sealed plastic case of dark blue color. Optimally suitable for placing a standard thermal drum at the bottom, prevents rapid defrosting of products from the refrigerator. Capable of maintaining a low temperature for about five hours. If you use an isothermal bag on a non.fire day and cut it off the lid, then the deadlines may increase.

Choosing a refrigerator in a car. the best models.

The very concept of the car hub includes three devices of different types at once:

Which of these refrigerators is suitable for you, what to pay attention to when buying and how to prevent mistakes when choosing and operating? Let’s deal with these questions in more detail.

Let’s start with the elementary. thermal lugs and thermal boxes.

This, in fact, is a very large thermos with soft (bag) or rigid (boxing) walls.

If you need products and drinks in it are cold, you should initially place them there cold.

To increase the efficiency of such “thermos” they are filled with cold accumulators.

These are such small containers with a refrigerant-water-salt solution or gel.

They can both buy and make them yourself (add several tablespoons of salt to a bottle of water and freeze the whole thing).

Thus, the cold will evenly go down and cool everything around you. No wonder in many models on the cover for this case there are s or special.fastening.

The effective size of the battery is calculated by the formula:

1 liter of the battery of cold = 10 liters of the refrigerator volume

Here are the actual results of the cold accumulators, after they are placed in plastic thermal boxes from different manufacturers:

Cold conservation time will also depend on the number of products inside the box.

The more there are, the less air remains, which avoids harmful air exchange. The measurements given in the table above were made with empty boxes!

It is not always so. In fact, everything will depend on the material of the manufacture and filling of the walls.

The real experience of the operation says that high.quality thermal drum on thermal insulating properties may not yield to a cheap plastic box.

Below is a sign of 5 hour tests of various thermal shutters with cold batteries inside.

As you can see, some of them show almost the same results with thermals (see the tests above).

At the same time, bags are much more convenient, compact and easier to transport.

In budgetary isolations, insulation is made in the form of thin foam sheets.

The largest heat losses will be observed here. Much more effective when liquid polyurethane is used as a filler.

It simply floods between internal and external walls and creates uniform thermal insulation.

Additional hatches in the case, which are advertised as a way to preserve the cold, in fact are useless.

Through them, it is supposedly convenient to get products without opening the lid entire. In fact, most people in the future are simply sealed with sealant.

Firstly, they do not use them. Secondly, the cracks turn into additional bridges of heat penetration.

In thermal drum, look first of all at how its upper part closes.

Thus, the cold accumulated inside is released out.

How to check the quality and thickness of thermal insulation at the refrigerator in the store? Put the box flat and press on the wall with your fingers.

If the wall “plays” and is easily affected, then the box clearly has voids and the isolation layer in it is minimal.

If thermal insulation is enough, then the wall will not be pissed off.

Conclusion from all of the above. If you have a choice, then it is better to overpay and buy a more expensive thermal drum than a cheap thermobox.

You will get about the same time saving products, but it will be more comfortable with it to go to nature or the beach than to carry a large, plastic bucket.

To increase the efficiency of thermal boxes and force them to cool the products not only due to “ice cubes”, refrigerators with the Peltier element were invented.

In everyday life, Peltier elements are most often used in wine cabinets.

Additional equipment

Many modern thermal drums boast of additional configuration. a set of dishes, special compartments, s for bottles, etc.D. Buy just such a bag or not is a personal matter for everyone. It is worth considering that a set of plates, forks and glasses may not be useful to you in nature or in the country, and and often will you use such a service is unknown. But such a bag will cost an order of magnitude more expensive.

practical in this regard are products for products. Even if your bag has fallen or rolled over, the products inside will not suffer and will not fall out.

Criterias of choice

When buying a cooler bag, you need to build on your needs. Analyze how and why you will use it and pay attention to the most important characteristics.

If the thermal drum is worn in the hands or on the shoulder, it is worth choosing a model with a volume of not more than 30 liters and weighing up to 1.5 kg. For romantic pair walks and family picnic, three-liters of up to 3 liters and weighing 500-600 grams are suitable for three. At a party with a lot of people, it is better to take several average containers with food (up to 40 liters) than one, which is difficult to deliver to place.

Auto travelers can afford isothermal bags and auto.chroniclers of any volume and mass. their size limits only the presence of space in the trunk.

As mentioned above, the design of modern thermal shutters provides for the presence of an external and internal layers separated by thermal insulation material. The outer layer is made of dense, waterproof synthetic fabric or from safe food plastic. The material of the outer layer should absorb heat, easily clean or wash, and also dry quickly. Inside is a synthetic fabric or polyethylene with a foil surface for better maintenance of heat or cold. If the inner layer is made of ordinary polyethylene-the time for preserving the desired temperature inside the container decreases to 2-3 hours.

In order for the cold inside the thermal container to remain for more than 2 hours, the thickness of the heat-insulating layer between the walls should be at least 0.8 cm. Thermal insulation 2-2.5 cm thick will support the desired temperature regime for 10-12 hours. Ideally, the walls should have a thickness of 3 to 5 cm.

The presence and type of cooling devices

The conservation time of the desired temperature is extended by cold batteries. flat plastic containers or dense plastic bags with a special filler inside. Before use, the batteries are frozen in the freezer for 5-7 hours, and then placed in special departments of bags-colds. Standard cooling elements have a volume of 250-800 ml. Depending on the size of the thermal drum, from 1 to 5 batteries is laid in it.

Cooling elements are divided into types depending on their internal filling. The following types are most common today:

• Water-salt. Hermetic plastic vessels filled with water-salt composition. Capable of maintaining the temperature from.20 to 8 degrees to 24 hours.
• Silicone. Flat plastic bags with silicone filler. Retain the temperature from 0 to 2 degrees. Effective up to 7 days. Suitable if you need to store products in coolness for a long time.
• Gel. Safe gel filler packages, which are based on carboxymethyl cellulose. Operate in a wide temperature range, t.e. They can not only cool, but also heat space. Effective for 6-16 hours.

The most popular are the cold gel batteries, due to their versatility, security and the possibility of applying in different situations.

For ease of operation, isothermal bags have a number of additional useful parts. The most significant of them are pens and locks.

Paired pens On the sides are present in most small and medium thermal shoes to carry them at short distances. If you purchase a large or average model and plan to wear it for long distances. make sure that the configuration includes shoulder straps. Soft linings on belts will become an additional plus during operation. Large cooler bags and isothermal containers, ideally, should be equipped with special wheels and a handle that extends, like suitcases.

Locks prevent arbitrary opening of the thermal drum, protect its contents from theft, will not allow you to penetrate inside a curious pets and will not let the products fall out in case of accidental falling. Better than others have established themselves Molniya castles, However, in some cases it is more convenient to use Velcro locks.

Some portable products for cooling products are equipped with disposable utensils and devices for installing it. Widely distributed Additional external and internal s.

How the Kholodnik bag works

The principle of operation of the cooler bag is very simple. It is as follows:

• Warm or frozen products are laid inside the product.
• Hermetically closed the heat dryer to the fastener.
• Over the next hours they try to open the product as little as possible.

Until the air from the outside gets into the thermal drum, the temperature inside changes very slowly.

How much time does the Kholodnik bag hold the cold

The operational qualities of the cooler bag depend on several points. In the calculation, you need to take the volume of the product, the degree of tightness and the thickness of the insulating layer. A high.quality device is able to keep a low temperature inside up to three hours.

If you use the Kholodnik bag along with the purchased or homemade cold battery, the term will increase to 6-24 hours. The longest products will remain frozen if the device is equipped with several batteries at once.

The insulating layer of the cooler bag should have a thickness of at least 8 mm

What temperature does the Kholodnik bag hold

If the thermal drum is made of dense material and is equipped with a reliable fastener, then even without cold batteries it will be able to hold the temperature 15 degrees lower than outside. But this will last no more than 3-4 hours. Then the products will still heat up, especially with frequent opening the lid.

When using cold accumulators, it is possible to reduce the temperature by 20-25 ° C compared to the environment. If the batteries are enough, then the products will remain in a deep freezing state from 12 hours to a day.

Attention! You can make a battery for a cold bag with your own hands. To do this, a saline solution is poured into a plastic bottle and freezed at.15 ° C during the night.

Table-02

Cold batteries are different. Mostly there are bags of strong film and flat plastic containers. If you hold such a product in the freezer, and then place it in a cold bag with products, it will not only help them to hold out in the heat longer, but also lower their temperature-at least at first. It is advisable to put products in the bag with chilled.

Cold batteries are different. Mostly there are bags of strong film and flat plastic containers. If you hold such a product in the freezer, and then place it in a cold bag with products, it will not only help them to hold out in the heat longer, but also lower their temperature-at least at first. It is advisable to put products in the bag with chilled.

We purchased several folding soft thermal shutters of different capacities. Tough isothermal containers left for the future. they are in a different price range, moreover, they occupy more space. Chose the products of three companies. two models from each. Judging by internal shortcuts, everyone has Chinese, although European and American brands. Volume. from 16 liters (bag with two compartments: 6 10 liters) to thirty,

Two words about the methodology. In each of the bags, we put one of the cold accumulator weighing 770 grams, previously cooled in a household freezer to a temperature of –25 ° C. Then the products were loaded. a pair of water bottles and one chocolate, after cooling them up to 4 ° C. It remains to observe how the condition of the products at an ambient temperature of 26 ° C will change within eight hours. Assessed extremely simple. they measured the temperature of the water in the bottles hourly.

The cold was held better than all the bag with two compartments, 6- and 10.lit. over, for testing, we used only a 10.liter compartment, and the 6.liter would certainly show higher results. but it turned out to be too few for our tests.

How to choose a cold bag: reviews of satisfied buyers

The acquisition of a portable thermal container takes any trips and long walks to a completely new level of comfort. Agree, in the summer months you can not always quickly find chilled drinks or ice cream on the highway, and sandwiches and other products spoil in the cabin in hours. The convenience of using the cooler bag is noted by all the owners of this miraculous interpretation. The cost of a mini-cold, judging by the reviews, pays off in the first weeks of use. After all, now you can always have any familiar dishes and foods, as well as chilled drinks at hand. And you do not have to look for them in an unfamiliar place, buying food of dubious quality at high in a cafe on the highway. The Kholodnik bag is an indispensable accessory for use in a car, in nature, on long trips by public transport (long-distance trains and buses) and in any places where you do not have a full-fledged household device that cools products.

Very often containers for food, the walls of which are covered with insulating material, are considered universal. But is there really cold bags and thermal shoes is one and the same? There are universal containers for products designed to preserve the initial temperature. It is worth noting that the same products hold both cold and heat equally well. However, it makes sense to use thermal drums on short trips, since in a few hours the temperature inside will begin to approach the indicators of the external environment. Packages working on this principle, today can be purchased for a moderate price in any supermarket. And this is a good solution if you bought a lot of frozen or chilled products and want to bring them to the house intact and safety. The main difference between the cooler bag and the thermal tower is a denser layer of insulating material and the presence of a cold accumulator. But at the same time, you can use a cooling container as a thermos if you pack products without a frozen generator.