Perancangan Klem Untuk Cetakan Vertical Pouring Di Laboratorium Pengecoran Logam Politeknik Manufaktur Bandung

In the foundry laboratory at Bandung Polytechnic for Manufacturing, there is a student practicum program where the student learns several molding methods that are often used. One of these methods is a vertical pouring method. This is a one of mold method in the foundry process where the object is positioned vertically (vertically) with the inlet position either at the bottom of the object or at the top of the object. In this experiment using the vertical pouring method with direct pouring from a top. This method is usually used for objects that are plate shaped or cylindrical. The advantage of this method can control shrinkage and minimizes the mold area. In the process, where the object will be made in limited quantities, the mold is tied and buried in sand. The problems are processing time is longer than Cup and Drug molds, and wears a lot of sand. For this reason, a tool for clamping vertical molds is designed. This tool is expected to reduce use of sand, and reduce processing time. This tool is made of steel. vertical pouring method becomes more effective and efficient by using clamps

The Impact of the Gas Inlet Position, Flow Rate, and Strip Velocity on the Temperature Distribution of a Stainless-Steel Strips during the Hardening Process

A non-uniform temperature across the width of martensitic stainless-steel strips is considered to be one of the main reasons why the strip exhibits un-flatness defects during the hardening process. Therefore, the effect of the gas inlet position in this process, on the temperature distribution of the steel strip was investigated numerically. Furthermore, an infrared thermal imaging camera was used to compare the model predictions and the actual process data. The results showed that the temperature difference across the width of the strip decreased by 9% and 14% relative to the calculated temperature and measured values, respectively, when the gas inlet position was changed. This temperature investigation was performed at a position about 63 mm from the bath interface. Moreover, a more symmetrical temperature distribution was observed across the width of the strip. In addition, this study showed that by increasing the amount of the hydrogen flow rate by 2 Nm3/h, a 20% reduction of temperature difference across the width of strip was predicted. Meanwhile, the results show that the effect of the strip velocity on the strip temperature is very small.

Intercomparison of nitrous acid (HONO) measurement techniques in a megacity (Beijing)

Nitrous acid (HONO) is a key determinant of the daytime radical budget in the daytime boundary layer, with quantitative measurement required to understand OH radical abundance. Accurate and precise measurements of HONO are therefore needed; however HONO is a challenging compound to measure in the field, in particular in a chemically complex and highly polluted environment. Here we report an inter-comparison exercise between HONO measurements performed by two wet chemical techniques (the commercially available LOPAP and a custom-built instrument) and two Broadband Cavity Enhanced Absorption Spectrophotometer (BBCEAS) instruments at an urban location in Beijing. In addition, we report a comparison of HONO measurements performed by Time of Flight Chemical Ionization Mass Spectrometer (ToF-CIMS) and Syft Proton Transfer Reaction Mass Spectrometer (PTR-MS) to the more established techniques (wet chemical and BBCEAS). The key finding from the current work was that all instruments agree on the temporal trends/variability in HONO (r2 > 0.97), yet displayed some divergence in absolute concentrations, with the wet chemical methods consistently higher than the BBCEAS systems by between 12 and 39 %. We found no evidence for any systematic bias in any of the instruments, with the exception of measurements near instrument detection limits. The causes of the divergence in absolute HONO concentrations were unclear, and may in part have been due to spatial variability, i.e. differences in instrument location/inlet position.

Rib Turbulator Effects on Crossflow-Fed Shaped Film Cooling Holes

Most studies of turbine airfoil film cooling in laboratory test facilities have used relatively large plenums to feed flow into the coolant holes. However, a more realistic inlet condition for the film cooling holes is a relatively small channel. Previous studies have shown that the film cooling performance is significantly degraded when fed by perpendicular internal crossflow in a smooth channel. In this study, angled rib turbulators were installed in two geometric configurations inside the internal crossflow channel, at 45 deg and 135 deg, to assess the impact on film cooling effectiveness. Film cooling hole inlets were positioned in both prerib and postrib locations to test the effect of hole inlet position on film cooling performance. A test was performed independently varying channel velocity ratio and jet to mainstream velocity ratio. These results were compared to the film cooling performance of previously measured shaped holes fed by a smooth internal channel. The film cooling hole discharge coefficients and channel friction factors were also measured for both rib configurations with varying channel and inlet velocity ratios. Spatially averaged film cooling effectiveness is largely similar to the holes fed by the smooth internal crossflow channel, but hole-to-hole variation due to inlet position was observed.

Pengaruh zonasi dalam kandang closed house terhadap kadar amonia dan dampaknya pada kualitas daging broiler di musim penghujan

<p>This experiment was conducted to determine the effect of zonation in closed house on ammonia levels and its impact on broiler chicken quality in the rainy season. The research was held in closed house, Faculty of Animal Husbandry and Agriculture, Diponegoro University. Three hundred and sixty broilers were divided into 24 groups (4 treatment, 6 placement groups of broiler): T1 (Zone 1, at the inlet position of the cage), T2 (Zone 2; ¼ of the length of the cage), T3 (Zone 3; ½ from the length of the cage ); T4 (Zone 4; ¾ of the length of the cage). During the study of ammonia levels, the temperature, humidity, and wind velocity inside and outside the cage were taken to obtain an overview of several factors that contribute to ammonia levels. The parameters observed were water holding capacity, pH, color, moisture content, fat content, and protein content. Water holding capacity and the color of the upper thigh meat increased significantly in the zone near the outlet (p &lt;0.05), but the water holding capacity and the color of the lower thighs and breast meat did not increase (p&gt; 0.05) in the zone near the outlet, but it has a darker meat color on the zone near the outlet. The pH did not show any significant difference (p&gt; 0.05) in the zone near the outlet. Water content followed by fat content of breast meat showed no significant difference (p&gt; 0.05) due to zoning. Breast protein content significantly increased (p &lt;0.05) in the zone near the outlet. It was concluded that placement in the zone near outlet had impact on the increase of water holding capacity, color, and protein content. Nevertheless, an increase in meat protein in the zone near the outlet is not followed by increased meat protein mass.</p>