ISTA Views

JANUARY | 2018

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> MORE ON PAGE 20 19 ista views • December 2017/January 2018 • In the example of the Figure 6, an inside-truck temperature pattern can be observed. From 7AM to 2PM, the inside-truck temperature increases from its daily minimum to its daily maximum. Then, the temperature is stable for 3 hours and then decreases for 14 hours to its minimum. This pattern was observed every sunny day in our data set. Minimum and maximum inside truck temperature was the only day- to-day variation and was dependent on the minimum and maximum outside air temperature. A correlation between minimum (Air and truck) and maximum (Air and truck) temperature has been established using a linear interpolation on the 19 recorded days. Min Truck (Min Air ) = 0.72 * Min Air + 16 Max Truck (Max Truck ) = 0.91 * Max Truck + 11 30 35 40 45 50 55 60 65 6:00:00 AM 7:00:00 AM 8:00:00 AM 9:00:00 AM 10:00:00 AM 11:00:00 AM 12:00:00 PM 1:00:00 PM 2:00:00 PM 3:00:00 PM 4:00:00 PM 5:00:00 PM 6:00:00 PM 7:00:00 PM 8:00:00 PM 9:00:00 PM 10:00:00 PM 11:00:00 PM 12:00:00 AM 1:00:00 AM 2:00:00 AM 3:00:00 AM 4:00:00 AM 5:00:00 AM 6:00:00 AM Inside truck temperature simulation (°C) °C Duration above 50°C Duration above 40°C Hypothesis worst case: Location: Arizona Max Air : 49°C Min Air : 38°C In Truck °F °C Max: 141.2 60.6666667 Min: 101 38.3333333 Number hours Above 30°C: 24 Number hours Above 40°C: 21 Number hours Above 50°C 12 Number hours Above 60°C 4 Figure 7 – Simulation of the inside truck temperature through the model in extreme historical conditions in June 1990 (Min Air = 38°C; Max Air = 49°C; Source: Intellicast website). The model can tell us how many hours the product will be exposed to temperatures over 30°C (24 hours), 40°C (21 hours), 50°C (4 hours) per 24 hours. Algeria (North) China Min Truck 29.5°C 29.5°C Max Truck 45°C 49°C (warm areas) / 55°C (warmest areas) Number of hours > 20°C per day 24 24 Number of hours > 30°C per day 20 20 Number of hours > 40°C per day 9 14 Number of hours > 50°C per day 0 7 (warm areas)/12 (warmest areas) Table 1 – The table below presents the result of the model in the different target areas. In Algeria the highest density of population are located in the North where temperatures are moderate. Temperature inside the truck can go up to 45°C, including 9 hours over 40°C, 20 hours over 30°C. In China, 2 main temperature areas have been considered: 1- The warmest locations where temperature can rise up to 44°C (Ex. Shanghai) and 2-warm areas (most part of China) where temperature can rise up to 36°C. The model has been cross checked with data from the literature (Leinberger, 2006; 2002) in Europe, USA and applied for China and North Africa. Table 1 shows the output of the model taking Min Air and Max Air temperatures of two targeted market areas (China and Algeria). The analysis of the temperature maps for those two locations allowed us to make a hypothesis of the air temperature profile and estimate the temperature profile some of our product (external layers of the pallet) will be exposed to. We can then simulate in a laboratory the impact of those temperatures on the product.

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