Good response, in particular high sensitivity, of polyvinylidene fluoride (PVDF) attracts a lot of research works on its manufacturing process and applications. Polarization is an important factor that is influential to the performance of PVDF. In this article, a new polarization method using ITO (Indium Tin Oxide) glass is proposed. Different from the conventional poling method using metal eletrode coated onto PVDF film, ITO glass is used as electrode to transmit the electric field voltage into PVDF film for poling. With the advantage of applying higher electric field in the process of polarization and eliminating the occurrence of flashover and arcing efficiently, this approach can thus make PVDF film gain better electric output response. Also, thinner film is constructed would be another advantage of sensitivity improvement. Comparison with conventional method for regular polarization area is carried out by using both FTIR and DSC equipment. Piezoelectric charge constant d 33 and electricity output response as well as sensitivity of PVDF are measured in experiment, which indicate ITO glass poling method is superior to conventional technique.

Harvesting energy using roof turbine ventilator and electroactive material has been investigated to verify its performance. Since electric power gained from a single piece of regular size is usually small, auxiliary device to vibrate multiple pieces of electroactive materials in order to harvest more power is required. In this paper, an attempt of using the developed nozzle wind collector associated with the popular roof turbine ventilator employed with gear mechanism to impact and vibrate a group of electroactive material to generate electricity is proposed. Number of blade and blade angle of the roof turbine ventilator are influential to the effectiveness of wind collection. Also, number of electroactive material employed on the turbine ventilator under the wind speed in environment eventually determines the efficiency of wind harvest. A simple model is derived to estimate the minimum driving force from the wind power that needs to overcome the inertia of the turbine ventilator mechanism and the electromechanical energy conversion of electroactive materials. Wind drag force is calculated by using CFD is assumed to provide such driving force. Various combinations of the blade angle, number of blade and electroactive material actuators are investigated in simulations. Optimum design concerning the environment wind resource and configuration of turbine ventilator is discussed. According to several case studies, a few of design trends is addressed for better efficiency of energy harvest. Since multiple electroactive materials are employed, circuitry design with parallel input sources is implemented to sum up the current and integrate the power.

Pengkondisian udara dalam ruangan sangatlah penting. Hal ini dapat mengurangi sick building syndrome (SBS) yang dapat mengganggu aktifitas penghuni. Salah satu cara untuk mengkondisikan udara adalah dengan ventilasi mekanik. Penempatan exhaust fan sebagai ventilasi mekanik guna mendapatkan posisi optimum perlu dikaji. Pengkajian dilakukan dengan melakukan simulasi rumah 12.5m x 8.2m menggunakan Autodesk CFD 2019. Simulasi dilakukan pada lima posisi penempatan exhaust fan untuk membandingkan suhu dan kecepatannya pada setiap ruangan. Hasil dari simulasi didapatkan perbedaan suhu udara dan kecepatan udara dari tiap posisi yang diambil pada setiap ruamgan dan dibandingan dengan Tukey yang digunakan sebagai metode perbandingan. Didapatkan bahwa posisi penempatan exhaust fan tidaklah berpengaruh signifikan. Exhaust fan dapat diletakkan dimana saja didalam ruangan. Yang perlu menjadi perhatian adalah volume udara yang disirkulasikan dalam ruangan, agar udara segar dapat masuk dan mengurangi SBS.

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Di dalam penggunaan berbagai sumber daya alam yang utama, pemakaian bahan bakar minyak bumi pada mesin diesel terus bertambah secara signifikan sehingga ketersediaan dari bahan bakar minyak tersebut yang bersifat non renewable dikhawatirkan. Pemanfaatan biodiesel dari minyak nabati saat ini sangat popular sebagaimana kebijakan pemerintah Indonesia saat ini telah diberlakukan untuk mengurangi kelangkaan bahan bakar minyak. Kulit pisang yang seringkali menjadi sampah rumah tangga dipertimbangkan dapat dijadikan minyak nabati sehingga minyak nabati tersebut dapat dicampur dengan minyak diesel untuk menghasilkan biodiesel. Di dalam penelitian ini, minyak nabati kulit pisang dicampur dengan minyak diesel dengan menggunakan kenaikan 5% minyak nabati tersebut. Biodiesel B10 dan B15 dari minyak nabati kulit pisang tersebut harus memenuhi spesifikasi Direktorat Jenderal Minyak dan Gas PERTAMINA untuk digunakan secara luas sebagai biodiesel alternatif untuk mesin diesel. Hasil uji kinerja dari mesin diesel menunjukkan bahwa biodiesel B15 dapat digunakan untuk mesin diesel