A pinboard by
Tobi Samuel Fadiji

PhD student (Mechanical Engineering), University of Stellenbosch, South Africa


Globally, ventilated paperboard packaging has been widely utilized particularly in the fresh fruit industry to protect the packed fruit against damage and preserve the fruit to meet the consumer needs satisfactorily. These packages go through the cold chain environment during distribution and they require venting to maintain the airflow between the surroundings and inside the package. The design of ventilated packages should be such that they can provide uniform air distribution and uniform cooling of the produce. However, these packages are faced with mechanical damage that may result from different loadings such as drop, impact, vibration, compression or a combination of all during handing and transportation. The presence of vent holes causes material loss of the package, which leads to a compromise in the stacking strength of the package and consequently result in produce damage. Therefore, the strength of packages is crucial for preserving the packed produce and the optimization of the packages is essential to save time, money and resources. This research was aimed at evaluating the structural behavior of ventilated packages. Finite element analysis was used to create models to study the buckling of four ventilated carton designs when subjected to stacking load. Experiments were used to quantify box compression strength. Results of mechanical strength evaluation showed a negative linear relationship between carton strength and vent hole area. Numerical results and experimental results were in good agreement. This study suggests the need for alternative package designs, giving consideration to the mechanical strength while still providing proper and adequate ventilation to the packed produce.


Mechanical design and performance testing of corrugated paperboard packaging for the postharvest handling of horticultural produce

Abstract: Publication date: July 2018 Source:Biosystems Engineering, Volume 171 Author(s): Tobi Fadiji, Tarl M. Berry, Corne J. Coetzee, Umezuruike Linus Opara Corrugated paperboard is the primary material used in the transportation, distribution and storage of many products, particularly horticultural produce. Corrugated paperboard packages provide protection to packed produce against mechanical loadings at all phases of distribution. These packages filled with produce are exposed to different hazards such as being dropped from height, transportation shocks, compression during stacking and exposure to the weight of other packed produce, all of which can damage produce. This review discusses performance testing of corrugated paperboard packaging, and highlights the manufacturing process and cold chain environment factors affecting the strength of corrugated paperboard packaging. The performance requirements for corrugated paperboard packages include appearance, structural stability and protection of contents. Testing the quality of corrugated paperboard and its various components, maintaining good control of manufacturing operations and environmental factors such as moisture, humidity and temperature are necessary for better understanding the performance of corrugated paperboard packaging. Advances in numerical techniques such as finite element analysis (FEA) offer new prospects and opportunities for replacing tedious, time-consuming and expensive experiments to improve the performance of corrugated paperboard packaging.

Pub.: 01 Jun '18, Pinned: 03 Jul '18

Susceptibility of apples to bruising inside ventilated corrugated paperboard packages during simulated transport damage

Abstract: The incidence of fruit postharvest losses and waste due to mechanical damage during handling is a major problem in the fresh produce industry Among the various range of force loading conditions experienced during handling and transportation, vibration is one of the key factors which may result in fruit bruise damage and the type of package used during handling of fruit could significantly affect the physical quality of the fruit. A simulated transport study was used to assess the susceptibility of apple fruit inside two ventilated corrugated paperboard (VCP) packages (MK4 and MK6) commonly used in fresh produce industry for packing apple fruit. An electro-dynamic shaker was used to excite vibrations at three frequencies (9, 12 and 15 Hz) and 0.9 g amplitude for four hours, which is usually adopted for truck transport simulation. Packaging transmissibility and incidence of bruise damage were measured at different frequencies. Results showed that both the incidence and severity of apple bruising were affected by package design and frequency. For both package designs at the three vibration frequencies investigated, packaging transmissibility ranged from 100 to 250%, with the highest transmissibility observed on the MK6 package with a lower length–to–height ratio at 12 Hz compared to the MK4 package. Apple fruit inside the MK4 package with higher length–to–height ratio had less damage than fruit inside the MK6 package. Irrespective of the package design, apple fruit on the top layer were more susceptible to bruising and the range of the proportion of bruised apples was between 50 and 74% at all the three frequencies, which are rather extreme conditions that usually occur when loads of packed fruit damage during transport.

Pub.: 16 Apr '16, Pinned: 03 Jul '18

Compression strength of ventilated corrugated paperboard packages: Numerical modelling, experimental validation and effects of vent geometric design

Abstract: Publication date: November 2016 Source:Biosystems Engineering, Volume 151 Author(s): Tobi Fadiji, Corne Coetzee, Umezuruike Linus Opara Ventilated corrugated paperboard (VCP) packaging is used for transporting fresh produce through a distribution system that requires maintaining a balance between uniform cooling of the produce and mechanical integrity of the package. A validated finite element analysis (FEA) model capable of predicting the compressive strength of two commonly used VCP packages is developed; the MK4 with higher length-to-height ratio and vent area compared to the MK6. The validated model was used to study the effects of vent geometric parameters such as vent height, shape, orientation, number and area on the strength of the packages. FEA results were in good agreement with the experimental results with a difference of 4.7% for MK4 and 8.2% for MK6. The MK6 had higher compression strength than MK4 with a difference of 11% and 17% at standard and refrigerated conditions, respectively. Results showed that the compression strength was lower by 11% and 16% respectively, for MK6 and MK4 packages when stored at low temperature (0 °C and 90% Relative humidity (RH)) compared to standard conditions (23 °C and 50% RH). With an increase in vent area from 2 to 7%, buckling load decreased by 8% for MK4 and by 12% for MK6. A linear correlation was observed between vent height and buckling load with R2 values of 0.8215 and 0.9717 for MK4 and MK6 packages, respectively. Results showed that vent number, orientation, and shape affected the buckling of the packages. Rectangular vent holes better retained the strength of the packages. Irrespective of the vent design parameters studied, the MK6 had higher buckling load.

Pub.: 04 Oct '16, Pinned: 03 Jul '18