จำนวน Repository ( 73 )
การพัฒนาผลิตภัณฑ์ผนังคอนกรีตมวลเบาด้วยการเสริมแผ่นโฟมอัดแน่นเพื่อเป็นฉนวนความร้อน
This research has objectives to study the production to find the proper size of steel wire mesh to test the properties and to study the implementation of high strength and thermal insulation cement-bonded fiberboard from coconut meal corncob fibers and steel wire mesh. The mixture ratio of cement-bonded fiberboard included Portland cement type1: sand: coconut meal fiber: corncob fiber: water: calcium chloride equal to 1: 0.2: 0.0125: 0.0375: 0.3: 0.03 by weight and 5 different sizes of steel wire mesh were reinforced. Casted by compression and sharking machine. Tested the properties follow the TIS.878-2537. From the results 1 mm of diameter and 1” of gab of steel wire mesh (? 1 mm # 1”) was the proper size to reinforce the cement-bonded fiberboard to get highest bending strength. Moreover this cement-bonded fiberboard can pass the required standard. The high strength and thermal insulation cement-bonded fiberboard from coconut meal corncob fibers and steel wire mesh has the possibility to construction as exterior building wall.
การใช้เศษหน้าดินขาวเพื่อเพิ่มประสิทธิภาพการป้องกันความร้อนภายในอาคารของอิฐก่อสร้างสามัญ
This research aims to produce scrap page kaolin of brick construction. The kaolin clay ratio of 100: 0 80:20 60:40 50:50 40:60 20:80 and 0: 100 by volume Add mixed with rice husk and rice 15 percent by weight A total of seven ratios. According to standard tests or TIS. 77-2545 ordinary story brick building. The moisture content and water absorption is increasing. While density Thermal conductivity resistance flexural and compressive strength tends to decrease. The best ratio of 80:20 by volume with compressive strength 43.16 kg / cm 2 and 24.93 percent water absorption. Criteria standard of TIS. 77-2545 requiring compressive strength not less than 35 kg / cm2 and water absorption must not be higher than 25 percent. Can be used in the manufacture of brick construction including building decorative wall can be developed into products. Because skin color and beautiful
การทำนายอัตราการถ่ายเทความร้อนในเงื่อนไขสถานะชั่วครู่ของเครื่องแลกเปลี่ยนความร้อนชนิดท่อความร้อนโดยใช้แบบจำลองสามมิติ
The aim of this study was to develop a three-dimensional transient condition model to predict the heat transfer rate of a heat pipe heat exchanger. This paper presents the details of the calculated domains which consist of the wall wick and vapor core. They were numerically simulated using the finite element method. The heat transfer rate values obtained from the model simulation can be used to design heat pipe heat exchangers. The values obtained from the model calculation were then compared with the results from experiments and the differences were 10.3% 10.4% and 6.7% for the working fluids of distilled water ethanol and R134a respectively. The working fluids of distilled water ethanol and R134a obtained heat transfer rates of 627.3 watts 522.8 watts and 836.4 watts from the experiments respectively.
การใช้ประโยชน์จากต้นมันสำปะหลังเหลือทิ้งผสมซีเมนต์ สำหรับเป็นแผ่นผนังไม้เทียมเพื่อป้องกันความร้อนภายในอาคาร
This research aims to study the using cassava pit wastes mixed with cement to particle board walls. The Portland cement type1: fine sand: tap water ratio is equal to 1: 0.5: 0.416 by weight. The ratios of cassava pit wastes to cement are used following: 0.05 0.06 0.07 0.08 0.09 and 0.10 by weight. The cassava pit wastes are crushed by plastic plastics granulators (pass sieve no.4). The casting of particle board walls use the compression machine in room temperature (30 – 35 degree of Celsius) and control 0.75 g/cm3 of density. The TIS 878-2537 standard (cement bonded particle board: high density) is followed to test the properties of particle board wall. Resulting the cassava pit wastes mixed with cement can cast to particle board walls and have good properties especially the thermal insulation property.
การออกแบบจานเบรกเชิงการสะสมความร้อนเพื่อความปลอดภัย
Admittedly a disc brake plays an important role in the auto part industry since it concerns directly with safety. Therefore the wide range of disc brake has been designed in order to develop its heat ventilation. Thus this project has designed a back-vented brake disc which is difference the current one (front-vented) and tried to create the test to find out the temperature diffusion of the disc brake with the hope to evaluate the coefficient of the heat convection varied by the temperature changing in both kinds of brakes under the forced heat convection in the steady condition. However the steady heat conduction and radiation value will not be counted because it is insignificant. The JASO C406: 2000 Standard is adopted as a guideline in the test. The outcome coefficient of heat conduction will be used in the simulation via the Finite Element Method (FEM) in order to study the temperature diffusion and heat ventilation of both kinds of brakes at each temperature level. Consequently the experimental work reveals then the heat convection coefficients of both kinds are unidirectional. The heat convection coefficient of the front-vented disc brake is 4.40 % in average higher than that of the back-vented disc brake. From the simulation the front-vented disc brake can ventilate the heat better than the back-vented disc brake at 3.02 % in average. It can be summarized that the front-vented disc brake has more temperature difference than the back-vented disc brake. Hence the front-vented disc brake likely gets more stress from the temperature than the back-vented disc brake and might be damaged during the operation more than the another type. Therefore this is tendency that the back-vented is safer than the front-vented brake disc for usage.