Experimental optimization of pressure distribution mechanism in a pneumatic maize planter for local working condition in Pakistan

This study was conducted to evaluate the feasibility of optimizing a series-type air distribution system in pneumatic planter transforming uniform seed placement through efficient vacuum pressure with the blower rotation for the planting of maize crop. A laboratory-based experimental facility was designed to test the performance of the pneumatic planter under four blower speeds (600, 900, 1 200, and 1 500 rpm) and three seed metering (SM) disc rotational speeds (17, 22, and 28 rpm). The most critical performance parameters were the vacuum pressure, the velocity losses of air, and the uniformity of seed-drop. To determine the effect of the blower rotation the on vacuum pressure, the vacuum pressure was observed at different locations in the air distribution system. The experimental results were confirmed with ANSYS simulation modeling the dynamics of airflow and pressure distribution in the series air channel-type. The physical tests and the simulation tests done to determine the behaviour of the seeds in the airflow (vacuum pressure) and accurate delivery of the seeds. The findings revealed that revolution of blowers and rotation of the disc created a statistically significant difference ( p < 0.05) in a vacuum pressure and seed distribution uniformity. The minimum optimal range of vacuum was –4.2 to –3.9 kPa that was created at 1 500 rotations of blower per minute (BR 4 ) and 22 rpm disc equivalence and the vacuum range was efficient on seed pick up and vortex seed loss. On the other hand, when the speeds of the blower were low (600–1 200 rpm) the vacuum pressure was weak (–0.24 to –2.28 kPa), with which the placement of the seeds was erratic. Even though BR 4 showed better performance, it also had the negative impact of increasing power requirement and fuel usage due to the heavy demand of the PTO on the tractor. The series type pressure distribution geometry optimized the performance of the pneumatic seed planter in terms of seed placement at BR 4 and disc speed of 22 rpm. Despite the enhanced reliability of operations when there is increased speed of blowers, careful thought should be put on energy efficiency.