scholarly journals Thermal performance of novel indirect passive solar dryer

2021 ◽  
Vol 30 (2) ◽  
pp. 293-303
Author(s):  
Manar Al-Jethelah ◽  
Hussam Deyab ◽  
Tadahmun Yaseen

An experimental investigation was conducted to study the performance of a novel indirect type free convection solar dryer. The novel and a conventional indirect passive solar dryer were built. Solar irradiation and temperature of different locations were recorded. The air at the drying chamber entrance, lower space, and upper space temperatures besides the thermal efficiency of the novel dryer were 68, 39, 49 and 85%, respectively, higher than the conventional one.

2017 ◽  
Author(s):  
Fatimah Batubara ◽  
Sari Farah Dina ◽  
Klaudia Kathryn Y. M. ◽  
M. Turmuzi ◽  
Fitri Siregar ◽  
...  

2014 ◽  
Vol 953-954 ◽  
pp. 16-19 ◽  
Author(s):  
Yuttachai Keawsuntia

This research paper presents the experimental results of drying of chili by using the active solar dryer and sun drying because of chili is a commercial agricultural product of Thailand. The active solar dryer consisted of a solar collector, a drying chamber and a chimney. The small fans were installed in the solar collector of active solar dryer to provide the air flow circulated in the solar collector and a drying chamber. Drying of chili of 20 kg from moisture content 84 percent wet basis to 10 percent wet basis following the Thai Agricultural Standard (TAS 3001-2010) showed that the use of the active solar dryer to make the drying time reduced about 28.7 percent compared with sun drying because of the hot air temperature inside the drying chamber higher than the ambient temperature about 10 to 15 . The quality of dried chili from the active solar dryer better than dried chili from sun drying.


2020 ◽  
Vol 13 (2) ◽  
pp. 84-93
Author(s):  
Muhammad Yasar ◽  
Raida Agustina ◽  
Mustaqimah Mustaqimah ◽  
Diswandi Nurba

Abstrak. Diantara permasalahan yang dihadapi oleh sektor usaha perikanan ialah  belum efisiennya teknis pengelolaan  dan tidak stabilnya kontinuitas produksi. Hal ini disebabkan oleh kurangnya sarana prasarana untuk mengolah ikan serta sistem pemasaran ikan segar yang masih konvensional, sehingga cepat membusuk apabila tidak diolah lebih lanjut. Penanganan dan pengolahan yang cepat dan tepat diperlukan untuk mengurangi resiko pembusukan dan dapat meningkatkan nilai jual hingga sampai kepada konsumen. Salah satu teknologi untuk meningkatkan masa simpan ikan ialah dengan cara proses pengeringan. Sebuah alat pengering ikan Green-House Effect (GHE) telah dikembangkan. Pengujian dan analisis alat pengering untuk ikan tersebut disajikan dalam makalah ini. Pengering surya ini menambahkan ventilator berupa exhaust fan guna memaksimalkan proses sirkulasi udara di dalam ruang pengeringan. Parameter yang diukur dalam pengujian ini adalah distribusi suhu, kelembaban relatif, iradiasi dan pengukuran kecepatan udara. Hasil penelitian menunjukan bahwa temperatur di dalam ruang pengering terlihat lebih tinggi yaitu 67°C dibandingkan dengan temperatur di lingkungan karena sifat absorber yang mampu menyerap panas. Sementara itu kelembaban relatif di dalam ruang pengering lebih rendah jika dibandingkan dengan kelembaban di lingkungan yaitu sebesar 30,1%. Nilai iradiasi surya yang diperoleh sangat berfluktuasi dengan nilai tertinggi adalah sebesar 180,6 W/m2. Kecepatan udara di dalam ruang pengering surya lebih stabil dibandingkan dengan kecepatan udara lingkungan karena adanya penambahan ventilator berupa exhaust fan. Hal inilah yang menyebabkan proses pengeringan menjadi lebih cepat.Performance of Green House Effect (GHE) Vent Dryer for Fish DryingAbstract. The problems that occur in the fishery business sector are inefficient and unstable continuity of production. The reasons for this include the lack of infrastructure for processing fish and also the very limited marketing of fresh fish due to its fast-rotting nature if not further processed. Fast and precise handling and processing are needed to reduce the risk of spoilage. One of the technologies to increase the shelf life of fish is the drying process. A greenhouse effect vent dryer type fish dryer has been developed. The testing and analysis of the dryer for these fish are presented in this paper. This solar dryer adds a ventilator in the form of an exhaust fan to maximize air circulation in the drying chamber. The parameters measured in this test are temperature distribution, relative humidity distribution, solar irradiation, and air velocity measurement. The results show that the temperature in the drying chamber is 67 ⸰C higher than the temperature in the environment due to the nature of the absorber which can absorb heat. Meanwhile, the relative humidity in the drying chamber was lower than the humidity in the environment, which was 30.1%. The value of solar irradiation obtained fluctuates where the highest irradiation is 180.6 W / m2. The air velocity in the solar dryer is more stable than the ambient airspeed due to the addition of a ventilator in the form of an exhaust fan. This causes the drying process to take place faster.


2021 ◽  
Vol 39 (4) ◽  
pp. 1313-1320
Author(s):  
Tadahmun A. Yassen ◽  
Manar S.M. Al-Jethelah ◽  
Hussam S. Dheyab

The present work experimentally studied two novel solar dryers’ designs, novel indirect solar dryer (NISD) and novel mixed indirect solar dryer (NMISD). The purpose behind this work is to compare the thermal performance of the proposed dryers with that of a traditional indirect solar dryer (TISD). The testing method involved building and thermally testing the three dryers. The NISD is a novel drying chamber with three absorbed surfaces. The NMISD consisted of a flat plate solar collector and NISD. The air temperature at the drying chamber entrance increased by 60% and 68% for the TISD and NMISD, respectively. In the lower space of the drying chamber, the air temperature was decreased by 35% while increased by 39% for the NISD and NMISD, respectively, compared to the TISD. The air temperature in the upper space of the drying chamber increased by 14% and 49% for the NISD and NMISD, respectively, compared to the TISD. The temperature variations through the drying chamber were -26%, 33%, and 3% in the TISD, NISD, and NMISD, respectively. The thermal efficiencies of the NISD and NMISD were 9% and 55%, respectively, higher than the TISD’s.


2020 ◽  
Vol 92 (3) ◽  
pp. 30901
Author(s):  
Suvanjan Bhattacharyya ◽  
Debraj Sarkar ◽  
Ulavathi Shettar Mahabaleshwar ◽  
Manoj K. Soni ◽  
M. Mohanraj

The current study experimentally investigates the heat transfer augmentation on the novel axial corrugated heat exchanger tube in which the spring tape is introduced. Air (Pr = 0.707) is used as a working fluid. In order to augment the thermohydraulic performance, a corrugated tube with inserts is offered. The experimental study is further extended by varying the important parameters like spring ratio (y = 1.5, 2.0, 2.5) and Reynolds number (Re = 10 000–52 000). The angular pitch between the two neighboring corrugations and the angle of the corrugation is kept constant through the experiments at β = 1200 and α = 600 respectively, while two different corrugations heights (h) are analyzed. While increasing the corrugation height and decreasing the spring ratio, the impact of the swirling effect improves the thermal performance of the system. The maximum thermal performance is obtained when the corrugation height is h = 0.2 and spring ratio y = 1.5. Eventually, correlations for predicting friction factor (f) and Nusselt number (Nu) are developed.


2019 ◽  
Vol 17 (3) ◽  
Author(s):  
Lamhot P. Manalu

Crop drying is essential for preservation in agricultural applications. It is performed either using fossil fuels in an artificial mechanical drying process or by placing the crop under the open sun. The first method is costly and has a negative impact on the environment, while the second method is totally dependent on the weather. The drying process requires a lot of energy in relation to the amount of water that must be evaporated from the product. It is estimated that 12% of the total energy used by the food industries and agriculture absorbed in this process. Due to the limitation of energy resources, it is important to keep researching and developing of diversification and optimization of energy This study aims to assess the use of energy for cocoa drying using solar energy dryer and bin-type dryer, as well as to determine the drying efficiency of each type of dryer. The results showed that the efficiency of the solar dryer drying system ranges between 36% to 46%, while the tub-type dryers between 21.7% to 33.1%. The specific energy of solar dryer ranged from 6.17-7.87 MJ / kg, while the tub-type dryers 8.58-13.63 MJ / kg. Dryer efficiency is influenced by the level of solar irradiation and the amount of drying load, the higher the irradiation received and more cocoa beans are dried, the drying efficiency is also higher and the specific energy further down.Proses pengeringan memerlukan banyak energi sehubungan dengan banyaknya air yang harus diuapkan dari bahan yang dikeringkan. Pengeringan dapat dilakukan dengan menggunakan pengering mekanis berbahan bakar fosil atau dengan menempatkan produk di bawah matahari terbuka. Metode pertama adalah mahal dan memiliki dampak negatif pada lingkungan, sedangkan metode kedua sangat tergantung pada cuaca. Diperkirakan bahwa 12% dari total energi yang dipergunakan oleh industri pangan dan pertanian diserap untuk proses ini. Mengingat semakin terbatasnya sumber energi bahan bakar minyak maka usaha diversifikasi dan optimasi energi untuk pengeringan perlu terus diteliti dan dikembangkan. Salah satunya adalah pemanfaatan energi surya sebagai sumber energi terbarukan. Penelitian ini bertujuan untuk mengkaji penggunaan energi untuk pengeringan kakao dengan memakai pengering energi surya dan pengering tipe bak, serta untuk mengetahui efisiensi pengeringan dari masing-masing tipe pengering. Hasil kajian menunjukkan bahwa efisiensi total sistem pengeringan alat pengering surya berkisar antara 36% dan 46%, sedangkan pengering tipe bak antara 21.7% dan 33.1%. Kebutuhan energi spesifik alat pengering surya berkisar antara 6.17-7.87 MJ/kg, sedangkan alat pengering tipe bak 8.58-13.63 MJ/kg. Efisiensi alat pengering dipengaruhi oleh tingkat iradiasi surya dan jumlah beban pengeringan, semakin tinggi iradiasi yang diterima pengering serta semakin banyak biji kakao yang dikeringkan, maka efisiensi pengeringan juga semakin tinggi dan kebutuhan energi spesifik semakin turun.Keywords: energy, efficiency, cocoa, solar dryer, bin-type dryer.


Sign in / Sign up

Export Citation Format

Share Document