**6. Results of experimental studies of thermophysical properties of fences**

In the first stage, Samples 1–3 were tested in the CHALLENGE CH600C (**Figure 3**) climatic chamber. The holding time of the samples was 22 hours; inside the TIC-1

#### **Figure 3.**

*General view of the CHALLENGE CH600C climatic chamber and the TIC-1 test chamber.*

#### **Figure 4.**

*Dependence of power consumption at the time of the experiment at a temperature outside* �*20°C (2) and inside the test chamber +40°C (3).*

chamber, the temperature was maintained at 40°C, outside �20°C (**Figure 4**). The average heat transfer coefficients of the cover and chamber are given in **Table 6**. The thermal insulation properties of Samples 2 and 3, containing thermal insulation "Corundum", were almost 2 times better. In Sample 3, the thickness of the layers of "Corundum" was 1.5 times thicker, but the heat transfer coefficient of the sample

*Experimental Research of New Design Solutions for Fencing Refrigerated Wagon Bodies… DOI: http://dx.doi.org/10.5772/intechopen.109744*


#### **Table 6.**

*Data obtained from experimental studies using a climatic chamber.*

decreased by less than 3% compared to Sample 2. This requires further research to select the optimal thickness of insulation of the "Corundum" type.

In the second stage, the determination of the heat transfer coefficients was carried out at the testing ground of the Scientific-Implementation Center "Wagons" in a room at an outside air temperature of 18–20°C without using a climatic chamber. Inside the test chamber, heating was carried out to 60–70°C. In this case, the power of the heating element – an electric lamp (25 W) – was reduced by means of a power regulator to 8.8 W.

Six prototype chamber covers were tested for 18 hours each. All parameters – power consumption, air temperature outside and inside the chamber and test duration were recorded. As a result of the experiment, the dependences of the external and internal temperatures and the average heat transfer coefficient on the experiment's time were determined, as shown in **Figure 4**. The results of the statistical analysis of the data obtained in experimental studies are shown in **Table 7**.

In **Figure 5a**, it can be seen that the air temperature in the test chamber increases during 5–6 hours, and then it stabilizes at the level of 58–75°C due to the transfer of heat from the test chamber to the outside. From **Figure 5b**, it follows: at the beginning of the experiment, during 5 h, the heat transfer coefficient of the test chamber drops sharply, which can be explained by an increase in the temperature difference between the outside and inside air (*tin* – *tex*). Then the heat transfer coefficient is stabilized and


#### **Table 7.**

*Data obtained in experimental studies without a climatic chamber.*

#### **Figure 5.**

*Dependences of the internal temperature (a) and the heat transfer coefficient of the test chamber (b) on the time of the experiment: 1 – Sample No. 1, 2 – Sample No. 2, 3 – Sample No. 3, 4 – Sample No. 4, 5 – Sample No. 5, 6 – Sample No. 6, 7 – Outside the test chamber.*

takes on a constant value. The heat transfer coefficients of the chamber covers are shown in **Figure 6**.

The heat transfer coefficients with and without a climatic chamber practically did not change. Their difference does not exceed 3%, which indicates a small dependence of the thermal conductivity coefficients of Samples 1–3 on temperature.

Repeated tests of Samples 1–3 confirmed (**Figure 6**) that the application of thermal insulation "Corundum" reduced the heat transfer coefficient almost twice. Thus, using "Corundum" as a layer of thermal insulation, it is possible to reduce the side wall thickness of refrigerated wagons and containers. For real wagons and containers, it is possible to reduce the insulation thickness by 20–30%. Insulation Samples 5 manufactured by "Regent Baltika" have the lowest heat transfer coefficients, but their thickness was significantly greater (135 mm) than Samples 1–3. Their

*Experimental Research of New Design Solutions for Fencing Refrigerated Wagon Bodies… DOI: http://dx.doi.org/10.5772/intechopen.109744*

**Figure 6.** *Average heat transfer coefficients of cover samples No. 1–6.*

application is promising, but it is necessary to develop technical solutions for their implementation.
