Ice is commonly used to preserve fish, but ice crushers are not always available in rural and remote areas of Bangladesh. A low-cost hand-operated ice crusher machine was developed in the Department of Farm Power and Machinery at Bangladesh Agricultural University. The machine yielded a throughput capacity of 21.6 kg min-1 with an average loss of 13.1%. The average time to crush a 10.6 kg ice block was 21.6 seconds. The total deformation, strain energy, maximum shear stress, and structural error were estimated as 0.0046 mm, 0.0031 MJ, 28 MPa, and 0.0025 MJ, respectively, for a single spike of the crusher. The average revolution per minute of the crushing cylinder was 493.6, with a maximum value of 634.7, and the maximum vibration frequency was 10.7 Hz. The maximum noise level during crushing operation was 92.9 dB, which was within the acceptable range. The machine's ergonomic assessment after operation yielded a satisfactory result. On average, the operators' blood pressure (systolic and diastolic), pulse rate, and respiration rate were 138.4 and 74.2 mm (Hg), 105.4 per minute, and 20 per minute, respectively. The results of the performance evaluation indicate that the device appears to be a suitable input for marginal fish farmers with inadequate access to electricity.
Key words: Crushing capacity, ergonomics, finite element analysis, fish preservation, marginal farmer
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