http://irplus.eng.usm.my:8080/ir_plus/viewContributorPage.action;jsessionid=D443C0C092B0FC25A372C2D253480AE9?personNameId=5891 Contributor Page for: Ong Wei Leek EngLib USM http://irplus.eng.usm.my:8080/ir_plus/institutionalPublicationPublicView.action;jsessionid=D443C0C092B0FC25A372C2D253480AE9?institutionalItemVersionId=7364 Kaedah moden dalam pengawalan pengeringan adalah berasaskan ideology ujikaji dan kualiti sebenar yang ditunjukkan oleh balak semasa pengeringan tidak diambil kira. Kekurangan maklumat mengenai keadaan sebenar balak telah menjadikan ia tidak mungkin untuk mengelakkan atau mengenal pasti kecacatan yang wujud semasa pegeringan berlaku walaupun dengan menggunakan mikroproseser moden.. Daya-daya dalaman dan pengujian seterusnya, perubahan lokasi komponen dan tahap daya baki adalah yang paling penting selain daripada pembentukkan bintik-bintik hitam pada permukaan balak. Tujuan utama permodelan adalah untuk menyifatkan pengeringan dalam bentuk tindakbalas daripada balak terhadap proses pengeringan dan perubahan dalaman balak secara matematik, supaya jangkaan tindakbalas dapat dibuat dan dipraktikkan dalam proses pengeringan serta menambahbaikkan jadual pengeringan. Yakni, kualiti balak selepas proses pengeringan adalah tujuan utama dalam bidang pengeringan, dan kuilitinya mesti dikenalpasti. Dalam projek ini, satu model pengering kayu balak yang berasaskan pum tenaga telah dihasilkan untuk menjalankan ujian tehadap kayu balak tempatan. Evaporator digunakan untuk merendahkan tahab kelembapan udara, di mana selepas itu akan dipanaskan oleh tenaga daripada kondenser. Proses merendahkan tahab kelembapan dan pemanasan ini adalah untuk mengeringkan kayu balak. Julat kadar pengeringan adalah dari 4.5 g/h hingga 7.3 g/h, dan untuk keempat-empat spesimen ini, tiada kecacatan dilaporkan. _______________________________________________________________________________________________________ Modern methods of drying control are based on empirical principles and actual wood characteristic occurring during drying are not taken into account. This lack of information regarding the actual condition of the wood makes it impossible for even modern microprocessors to avoid or recognize the occurrence of drying defects. Internal stresses and the resulting checks, creep components and residual stress levels are seen as the most important drying defects besides discoloration of wood. The purpose of modeling is to mathematically describe drying in terms of the response of the wood to process and material variables so that one can estimate the responses as well as gain insight into drying and for improvement of drying schedules. However, due to the complexity of the drying phenomenon there has been much debate as to the methodology and form appropriate to the academician, often fall short of their potential due to a lack of experimental data, over-simplification, or unknown coefficients. As a certain wood quality after the drying process is the main aim of the dried wood, the quality must be defined.31 In the current project, a heat pump assisted timber dryer was developed to carry out experiments on drying of local timbers. The evaporator of the heat pump dehumidified air, which was then heated by the condenser heat. This dehumidified and heated air was used to dry the timber specimen. The moisture extraction rate range from 4.5 g/h to 7.3 g/h, and for the four specimen, no defects were establish. Thu, 05 Nov 2020 14:50:25 +0800 institutional_item_version_id:7364