The heat transfer of heating radiators is a comparison table of cast iron, bimetallic, aluminum and steel batteries

Heating systems are essential to maintaining a warm and comfortable environment in our homes. The radiator is a vital part of these systems because it effectively distributes heat throughout our living areas. But with so many different kinds of radiators on the market, it can be hard to decide which one is right for you. Using a comparison table, we will examine the heat transfer capacities of several radiator materials in this article, including cast iron, bimetallic, aluminum, and steel.

For many years, cast iron radiators have been a common option for home heating. Cast iron radiators are renowned for their sturdiness and capacity to hold heat for extended periods of time. They offer reliable warmth even after the heating system has been turned off. To reach their ideal temperature, they can, however, take longer to heat up at first.

Conversely, bimetallic radiators provide a blend of longevity and efficiency. Bimetallic radiators offer a well-rounded approach to home heating by fusing the quicker heating qualities of steel or aluminum with the heat retention qualities of cast iron. They take less time to warm up and disperse heat evenly across the space.

Aluminum radiators are highly valued due to their rapid heat transfer and lightweight design. Aluminum radiators are lighter and take less time to reach operating temperature than cast iron radiators, which can be difficult to handle and install. Aluminum is also a highly conductive material, which facilitates the efficient and rapid transfer of heat.

For homeowners looking for cost-effective heating options, steel radiators present an additional choice. Steel radiators still retain and distribute heat well enough, despite being lighter than cast iron radiators. They are a popular option for people on a tight budget because they are frequently less expensive than aluminum or cast iron radiators.

Homeowners can choose the type of radiator that best meets their heating needs by comparing the heat transfer characteristics of cast iron, bimetallic, aluminum, and steel radiators. When designing a cozy living space, each radiator material has particular advantages to take into account, regardless of your priorities: affordability, efficiency, or durability.

How to calculate the heat transfer of heating radiators per square meter

The consumer can find the thermal power of a single section or an entire panel of a given size in the documentation that comes with the product. Since these are highly arbitrary, you shouldn’t put all of your faith in them. They need to be further refined to actual values. The radiator’s heat conductivity must be calculated in order to determine.

Prior to this, you had to dispel the widespread belief that aluminum batteries have the best heat transfer because they are made of non-ferrous metal. It is worthwhile to argue from the outset that the batteries are not made entirely of aluminum, but rather an alloy consisting of silicon and aluminum called silumin, whose indicators are significantly lower.

Radiators made of steel, bimetallic, and cast iron can all somewhat be said to have this quality. When the difference between the room’s air temperature and the coolant’s average temperature is 70 °C, the power parameters listed on the heating device’s passport match reality. This phenomenon is denoted by the sign Δt and is known as temperature pressure. The following formula is used to make the calculation:

Δt = (tair – tfeed + tReturn)/2

According to the manufacturer’s logic, the computation should yield a temperature of 70 degrees. Next, you can use the following formula to determine the coolant’s average temperature:

(\t + t air) = (tfeed + tReturn)

For instance, using the thermal power of one bimetallic section (200 W) reported by the manufacturer, ΔT = 70 0 C, and the average room temperature (22 0 C), we obtain the following outcome:

(tfeed + tReturn) equals 2 (70 + 22) or 184 0 seconds.

Determine each one’s value independently, taking into account the normative difference of 20 degrees between the presentation and the reversal:

Tfeed = 102 0 s (184 + 20)/2

(184 – 20)/2 = 82 0 s is the return time.

Assuming that the water in the supply pipe boils and the coolant in the exhaust pipe exits at 82 degrees, this heat transfer calculation demonstrates that one section can produce 200 W.

In actuality, this phenomenon is just not possible. It is a fact that water heated by domestic water heating boilers cannot be heated above 80 degrees. Even in these most extreme circumstances, the coolant will enter a radiator at a maximum temperature of roughly 77 0 C, and the temperature drop will be about 40 0 s. This leads to the conclusion that one section of the bimetallic radiator will actually transfer only 100 watts of heat, not 200.

You can use the heat transfer table with lowering coefficients to make the calculation simpler. To do this, Δt is calculated using the above formula and the planned temperature in the house and coolant.

Dressing coefficient values table

They locate the matching coefficient in accordance with the table and multiply it by the thermal power of one section of the bimetallic radiator’s passport value. Then, in the scenario under consideration, 1 m 2 of the premises will need to be heated by a heat transfer of 200 W x 0.48 = 96 W.

It will require about 1 kW of thermal power to heat 10 m 2, and the number of sections needed is equal to 1000/96 = 10.4 pieces. Two batteries of 10 and 11 sections should be placed beneath any two windows in the space.

Thermal power vacation standards

Buildings and other structures’ heat supply systems are designed with reference to the regulatory document SP 60.13330.2016. The rules govern, among other things, the construction of internal heat supply systems on the grounds of newly constructed and renovated buildings and structures. Based on the specifications of SNiPs GOST 30494-2011 and GOST 32415-2013, SP was created. Based on these, a room with a 10 kV area was assigned a 1 kW heat power rate. m., featuring one window, one outer wall, and a ceiling height of up to three meters.

The correction factors are introduced for the precise determination of nominal heat transfer when changing the initial conditions for heating the room in one direction or another (larger or smaller area, different number of windows, etc.).

K1: Windows

• Double frame – 1.27;
• double -glazed window – 1.0;
• Triple double -glazed window – 0.85.

K2: Wall thermal insulation

• low – 1.27;
• masonry in 2 bricks + thermal insulation – 1.0;
• High quality – 0.85.

• 0.5 – 1.2;
• 0.33 – 1.0;
• 0.1 – 0.8.

K4 is the room’s average winter temperature in degrees

• 35 – 1.5;
• 20 – 1.1;
• 10 – 0.7.

K5: the quantity of exterior walls

• 1 – 1.1;
• 2 – 1.2;
• 3 – 1.3;
• 4 – 1.4.

K6: the spaceabove the space

• cold attic – 1.0;
• The attic is 0.8.

K7: Ceiling Height (Meters)

• 2.5 – 1.0;
• 3 – 1.05;
• 3.5 – 1.1.

Heat transfer from one radiator section makes up the final result. In the larger method, private is rounded to the nearest whole number (10.4 – 11 sections).

Comparative tables of heat transfer of radiators of different types

Heat transfer is measured in WT/m 2, as was previously mentioned. This figure is regarded as a representation of efficiency. A comparison of the thermal capacities of various heating battery types and designs is crucial when selecting the right one for the consumer.

We hope to make it easier for homeowners to make decisions by comparing four types of heating radiators: cast iron, bimetallic, aluminum, and steel. Regarding cost-effectiveness, durability, and heat transfer efficiency, each type of radiator has advantages and disadvantages. The information is presented in an understandable table format so that readers can quickly identify the main differences and select the radiator that best suits their needs. Whether it’s the sleekness of steel, the lightweight appeal of aluminum, the efficiency of bimetallic, or the time-tested dependability of cast iron, we offer a thorough overview to assist readers in making decisions about insulation and heating for their homes.

The dependence of the heat transfer of the radiator on the temperature of the coolant

One radiator section’s passport thermal power is calculated using the standard coolant temperatures at the heating device’s input (90 0 C) and output (70 0 C). These circumstances concern networks of centralized heat supply.

The temperature differential in private homes with autonomous heating systems may differ. In this instance, heat transfer 1 may vary greatly from the manufacturer’s stated values. The temperature of the coolant in the supply pipe directly affects the thermal power of the heating device. The greater its size, the higher the battery’s heat transfer; conversely, the lower the radiator’s thermal power as the coolant heats up less.

Thermostats, which are sliced into the radiator’s input pipeline, are used to prevent unplanned temperature spikes. Thermal drives can be adjusted manually, semi-automatically, or automatically and can be controlled online.

1. Thermal losses through the roof are: 25 – 30%.
2. Through windows: 10 – 15%.
3. Heat loss through the floor: 10 – 15%.
4. Losses through walls: 10 – 15%.
5. Juits: 10 – 15%.
6. Through the pipe (if furnace heating): 20 – 25%.

How to increase the efficiency of the existing heating system

Experts advise the following actions to boost the effectiveness of the current heating system:

• insulate the enclosing structures outside the housing (walls, foundation, basement and attic);
• replace the old wooden window frames with double -glazed windows;
• Stick screens from foil behind the radiators on the walls;
• periodically open Maevsky cranes for the descent of air traffic jams in radiators;
• In the presence of cold walls, they are insulated from the inside with heat -insulating materials.

The owners of the home or apartment will notice an improvement in the heating devices’ ability to transfer heat right away after these occurrences. In the building materials market, a wide range of materials are available to warm the walls from the inside, including textured plaster, cork sheets, gypsum tiles, and decorative polyurethane panels. These materials not only provide insulation for the room but also enhance its aesthetic appeal.

Rule 2: The connection method has a big influence on how much the efficiency of heating devices changes. It is possible for the heat supply pipes to be supplied unilaterally or bilaterally. In order to get the battery power closer to the stated passport value of heat transfer, a double-sided connection diagram is helpful. Experience has shown that it is preferable to use a one-sided battery connection when there are less than 20 sections in a single room.

In the picture below, the efficiency of the sections during the connection of double-sided pipes.

In the image illustrating the sectional efficiency during the unilateral pipe connection.

How to calculate the heat transfer of one heating radiator section

We propose using the online calculator to calculate the required number of sections of the bimetallic radiator per square meter.

You can adjust the heating devices based on the quantity in each battery thanks to their sectional design. This makes it possible to modify thermal power by changing the radiators’ heat transfer surface.

Sectional versions of batteries are made of cast iron, aluminum, and bimetallic materials. As previously stated, each section has a pre-declared passport thermal capacity intended for typical heating device operating conditions when it enters the heat engineering market.

The characteristics of the space where heating radiators are installed must inevitably be considered in every calculation of heat transfer. Correction factors were created in response to this (refer to the preceding chapter, "The Norms of Vering Power Vacation"). They obtain the final value of the thermal power of the first battery section by substituting their actual values in the calculation.

Selecting an appropriate heating radiator for your house is essential for effective heat distribution and reduced energy usage. We have examined the distinctions between cast iron, bimetallic, aluminum, and steel radiators in this comparison table.

Cast iron radiators are renowned for their longevity and timeless style. They provide consistent heat retention, which makes them perfect for high-ceilinged or older homes. They might need more energy to run, though, and they can take longer to heat up.

Bimetallic radiators combine the advantages of two materials, usually aluminum and steel, providing durability and efficiency. Their ability to heat up rapidly and disperse heat evenly across a space makes them a popular option for contemporary homes.

Because aluminum radiators are lightweight, responsive, and require less water volume than other types, they can save energy. They also heat up quickly. They might not, however, hold heat as well as other materials.

Steel radiators, which have a sleek appearance and rapid heat distribution, are frequently the most affordable choice. On the other hand, in comparison to other materials, they might be more prone to corrosion over time.

In the end, the ideal option for your house will rely on things like your spending limit, your taste in design, and the particular heating requirements of your room. You can make an informed choice that will keep your house cozy and energy-efficient for many years to come by taking into account the data this comparison provides.

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