16 research outputs found
การพัฒนาเครื่องอบแห้งข้าวเปลือกแบบไหลต่อเนื่องด้วยเทคนิคการแผ่รังสีความร้อนในแนวรัศมี
No full textวารสารวิชาการและวิจัย มทร.พระนคร, 12(2) : 37-46The objective of this research was to design and development of a continuous flow paddy dryer with infrared radial radiation technique. The prototype of dryer consists of two concentric circular cylinders, cylinders, which the paddy drying chamber is height of 1 m. The inner cylinder has diameter of 26.5 cm made from glasses and outer cylinder has diameter of 29.5 cm made from perforated (1.75 mm) steel sheet. At the center of cylinders installed 1,200 w of electric infrared heater. A hopper was installed on the top of the chamber while 120 w of blower and paddy flow control were installed at bottom of chamber. The performance of the dryer in terms of specific energy consumption (SED), drying rate (DR) and quality of paddy i.e. head rice yield (HRY) and whiteness index (WI) were evaluated by drying 15 kg of paddy with initial moisture content of 23-26% (w.b.) by using the drying conditions of 80oC of drying chamber temperature, 1.075 m3/min of air flow rate and 0.837, 1.228 1.875 and 2.308 kg/min of paddy flow rate. The results found that paddy flow rate at 1.875 kg/min is the optimum condition because gave the highest DR, lowest SEC and rice qualities (HRY and WI) closely to control.Rajamangala University of Technology Phra Nakho
Empirical modelling of temperature in fogging greenhouse
No full textThe objective of this article is to evaluate the inside temperature of greenhouse and efficiency of fogging system under the influence of solar power. A 50% off sun shading roof was selected to test in this study. Testing is divided to 2 cases. Case I Measuring all of parameters without operate the fogging system and ventilation between 9.00 a.m. to 5.00 p.m. (Thailand’s time zone). Case II Measuring all of parameters with a fogging system that was controlled the relative humidity below 80% all day. The results show that the highest temperature in greenhouse is 50.13oC (no fogging and ventilation). the developed empirical model has an error 6.33% between numerical results and measured air temperature. In case of neglected solar power, the model showed that the fogging system can reduce the temperature in greenhouse in range of 7.05°C (18.44%) and the efficiency of fogging system is quite high (value is 57.36%). The important factor that influents on the air temperature in greenhouse is solar power. If we need to control the atmosphere in greenhouse by fogging system than the reduction of solar power is the most important controlling factor
Kinematics motion of paddy in hot air pulse flow
No full textThis research aims to study the characteristic of paddy motion under the hot air pulse flow in the drying tube length 2 m by using the kinematics motion analysis. The equations of paddy motion are analyzed to evaluate the pattern of paddy motion, total distance that the paddy can travel through the drying tube and Reynolds number of paddy. Results found that Model I, II and III consume the paddy travel time of approximately 1.3, 5.0 and 2.2 s and give a total distance of 2.6, 2.7 and 2.5 m and they have maximum travel velocity of 4.12, 1.37 and 1.85 m/s respectively. When considering the Reynolds number, the models I, II and III give the most values from similar calculations with 1,837, 1,816 and 1,821 respectively. Based on various parameters from all of models, Model III was the closest characteristic of paddy motion to the actual movement in the system
Optimization of carrier agents using mixture design for tamarind powder production
No full textThis research investigates the collective use of maltodextrin (MD), octenyl succinic anhydride (OSA), and gum arabic
(GA) to produce tamarind powders using the double drum dryer method. In this study, seven carrier mixture formulations were
specified using a simplex lattice mixture design and the physicochemical characteristics of the tamarind products associated with
the MD-OSA-GA combinations were assessed. Graphical optimization was utilized to identify the optimal MD-OSA-GA
concentrations that would produce a tamarind powder with the essential physicochemical characteristics that would closely
resemble the fresh tamarind pulp including total solids (TS), viscosity (VS), pH value (pH), and total acidity (TA). The optimal
mixture concentrations were 61.52 g, 28.48 g, and 10.00 g/100 g for MD, OSA, and GA, respectively, with the tamarind powder
possessing 39.88% TS, 0.27 VS, 3.04 pH, and 9.31% TA
Humidity Control for Air Circulation in the Drying Process
No full textRecycling exhaust air is acknowledged as a method to reduce the energy consumption of agricultural products in the dryer. This study investigates the performance of an air circulation system at a laboratory scale and develops a feedback control compensator for optimizing the drying air circulation process. A servo motor is employed to drive a valve, to feed the exhaust drying air with high temperature and humidity back in different proportions. The system is controlled using an Arduino DUE microcontroller, which communicates data with MATLAB/Simulink. The system identification methodology is employed to analyze the mathematical model of the system. The result indicates that the response of the system meets the acceptance criteria when the percent overshoot is less than 25%, and the settling time is within 60 seconds (with a 2% error tolerance). Evaluation of control system performance during equilibrium employs R2 and RMSE values
Effect of Temperature on the Physicochemical Properties of Tamarind (Tamarindus Indica) Powder
No full text
การอบแห้งพริกด้วยเครื่องอบแห้งอุณหภูมิต่ำที่เสริมการทำงานด้วยเครื่องอุ่นอากาศเทอร์โมอิเล็กทริค
No full textวารสารวิชาการและวิจัย มทร.พระนคร, 14(1) : 82-96This research objective was to apply thermoelectric module model TEC12710 as a preheater and dehumidifier for red chilies dryer. The heat side and cool side of Thermoelectric module affected by supplied electricity were used to produces the low humidity and warm air in preheater before charging to the main electric heater of dryer. Fresh red chilies were selected as a sample in the prototype testing during the use of preheater assisted main heater and using only main heater. The test results are compared with the sample dried under the natural sun drying. The experimental results show that the preheater can condense the moisture in air with the highest MER of 0.083 kgwaterh-1 at cold side of thermoelectric module
and can heat the air up in 10°C of temperature with hot side of thermoelectric module. The final moisture content of sample is only 10%wb with the slightly changed in color when compared with the sample from sun drying. The using of preheater with main heater gives a higher specific moisture extraction rate, lower specific energy consumption, 14 MJ energy used and can dry faster than 10 h when compared with the using of only main heater.Rajamangala University of Technology Phra Nakho
