Refrigerated Environment CFD Optimisation Case Study

When a client found issues with temperatures above the required limits in one of their designed refrigerated truck enclosures, Jesmond Engineering created a revised design by assessing the causes of the issue and optimising the airflow in the refrigerated space to allow cooling to reach all areas of transported products, avoiding localised areas of defrosting.

Refrigeration units used on trucks are essential when transporting termperature-sensitive goods, ensuring that the products are kept at the correct temperature during transport and arrive in the best condition. These units are built to handle fluctuating external temperatures, however the client had found temperatures above permitted levels in the top rear part of an enclosure and turned to Jesmond Engineering for help.

The challenge for Jesmond Engineering was to use CFD analysis to assess the airflow and pressure from the refrigerator unit, while overcoming physical geometric restrictions due to loading, to show what was causing these higher temperatures and how these could be overcome.

Jesmond Engineering created accurate CFD models from engineering drawings to solve for turbulent flow velocities and pressures. The CFD model geometry was exported for further processing and simplifications were made to reduce the time invoved in running the computations and limiting the associated expense, to ensure the analysis was as cost-effective as possible whilst maintaining sufficient accuracy and staying within the client’s budget.

​Simulations were conducted and an optimisation study was performed to create an initial idealised design that was free of manufacturing constraints. This was then followed by Jesmond Engineering to define a practical retrofit design which was successfully used to modify over a hundred operational refrigerated environments.

The initial CFD results of the problem provided by Jesmond Engineering validated the client’s observations of the issue. ​ The optimised retrofit design provided, which included an aerodynamic flute integrated into the central airflow duct, showed significant improvement in airflow distribution. ​ Velocity profiles showed that bulk flow was dispersed almost completely in the existing design at half the trailer length, but greatly improved in the revised design, extending towards the rear of the trailer. ​ The rear bulkhead velocity increased by 300%, with its lower region achieving flow velocities equal to those of the central airflow duct outlet. ​ Physical performance testing confirmed the accuracy of Jesmond Engineering’s CFD predictions.

The optimised retrofit design resolved temperature issues and improved the airflow efficiency in the refrigerated unit. ​ The client successfully manufactured the recommended components, retrofitting the existing fleet and incorporating the new design into their fleet of new-build vehicles. ​ The solution enhanced operational performance, ensuring compliance with temperature regulations, saving the time and cost of spoiled food products and improving the overall reliability of the refrigerated environments.