[en] Analysis of the efficiency improvement of the shell and tube type of the Kartini reactor's Heat Exchanger (HE) have been carried out after the flow direction system was modified from the parallel flow to the counter flow system. The HE was tested by operating the reactor at the power level of 100 k W, until the temperature of the water coolant reached the steady state condition. The efficiency and other HE's parameters was investigated by using the ^SIMULTAN^method. From the experiment it is known that the inlet and outlet primary and secondary water coolants are T_i = 38^oC, T_o = 35^oC, t_i 32^oC and t_o = 33^oC respectively. The investigation and analysis show that that HE's efficiency is η= 45,5 % due to U a= 674,79 W/m K, LMT = 3,27 and NTU 0,835. From the analysis can be concluded that the increase of the HE's efficiency is 2.5 % compared to parallel flow and the decrease is 6.7% compared to the HE's efficiency as soon as after having been cleaned in 1994

[en] The computation and analysis of the heat transfer coefficient correction factor the shell and tube type of the Kartini reactor's heat exchanger (HE) has been carried out. The computation of the correction factor was done by measuring of the actual dimension of HE. As known that the shell and tube type of the Kartini reactor's has been opera-ted for more than 15 years. Due to the scraping and rusting occur at the buffle, the total heat transfer coefficient correction factor Ft was decrease. At the later computation, it is found that it's value is 0,4669 or differ of 0,1331 compared to the prediction standard value. So far, if the rusting and scraping of the secondary water coolant to the buffle is linear to the earlier HE's operation time, it is predicted that the function of the buffle will crisis approximately in the year of 2002/2003 or 7,5 years again

[en] The computation and analysis of P3TM's power supply for accelerator laboratory has been carried out. The purpose of analysis is to prepare the electrical energy which will be used for accelerator laboratory in the future. The load factor and residual electrical power was computed by using several data i.e electrical bill, energy consumption from April 1998 up to March 1999 and the peak current load out from transformer which is measured inside electrical central box. From the analysis it is known that the electrical load factor of P3TM is 27.4 %, power factor 0.78 and the average power consumption is 189.6 KVA. If the load forecasting factor is 50 %, the maximum electric power requirement for P3TM is about 300 KVA and the residual power supply is 390 KVA. If maximum electrical demand for accelerator is less than 390 KVA, then the electrical power for accelerator itself can be served by new special line for accelerator and by improving the power supply quality. In case the power level has to be increased, the most economical can be achieved by increasing electric power from 690 KVA to the optimum level of 860 KVA with condition that peak operational power of accelerator is less than 560 KVA. (author)

[en] On behalf of increasing reactor power from 100 kW to 250 kW have beencarried out the analysis and determination of the Plate type Heat Exchanger's(PHE) cooling load. The analysis was carried out based on the present PHE'sperformances and the maximum water temperature allowed i.e T₁₁ = 41 ^oC.From the experiment where reactor operated at 100 kW for 6 hours or more atthe steady state condition was known that temperature of cooling water are :T₁₁ = 37 ^oC, T_o1 = 33.71 ^oC, T₁₂ = 28.84 ^oC and T_o2 = 29.64 ^oC,so that PHE's effectiveness is ε = 0.394. To analyse PHE's coolingload at 250 kW was estimated secondary input water temperature T₁₂ = 28.64^oC. The result shown that at reactor power level of 250 kW or 215x10³kcal/hr the flux mass of primary pump is 196.4 gpm which related to pumpingpower 13 Kw and the pipe diameter of 3 inch. While for secondary side : fluxmass is 254.4 gpm, pumping power 17.34 kW and the pipe diameter 4 inch. Inthis case also known that water temperature out from PHE are T_o1 = 36.13^oC for primary and T_o2 = 32.4 ^oC for secondary respectively. (author)

[en] A determination of the Th-232 content in the ore has been performed usingboth the Neutron Activation Analyses (NAA) and the Delayed Neutron Counting(DNC) to some 9 ore-samples. The results indicate that the determinationusing NAA and DNC methods give 6.7 % and 1.39 % of error respectively whichcorrespond to 4590 ± 299 ppm for the NAA and 2116 ± 295 ppm for the DNCmethods respectively. It was indicated also that though the accuracy of theNAA was worse in comparison with the DNC method, it gives a faster time tocomplete than that of DNC method. (author)

[en] It has been analyzed the cooling capacity for 350 keV/20 mA electron beam machine rooms at P3TM. The analysis of cooling load based on the building construction and the device for supported the electron beam machines operation, were obtained head dissipation and provided the cooling load. From the result it can be determined that for cooling the electron beam machine rooms with 945 m cubic of volume and supporter device in the room, in order to reach the air condition about 20^o C of temperatures and 50 % of relative humidity for the electron beam machine rooms, it was needed the air conditioning system with total cooling capacity about 213.000 BTU/Hours. (author)

[en] A computer programming that could be used to calculate the fuel temperature and the reactor core, has been developed. The inside fuel temperature was calculated by explicit method. First, the differential partial equations were arranged the temperature as a function of the fuel radius and lime. T = f(r.t), and then the equations were transformed into the finite difference equations that could be solved numerically by the computer. The convection heal transfer coefficient between the fuel and the coolant was calculated basically by the free convection phenomena that followed the equation Nu = f (Gr, Pr). By this computer programming, the fuel and the core temperature in a certain condition of the reactor power and the fluid could be predicted

[en] Preliminary design of cooling a system for DECY 13 MeV cyclotron has been done, which will be installed in building 05 of PTAPB BATAN. The design is based on a predetermined layout and installation of all equipment, those are the magnet system, RF-dee, ion source and vacuum system. The calculations include heat transfer in chiller, fluid properties, flow and pump head, those are calculated from the pressure drop on each equipment, major losses of elevation, as well as minor losses which consist of friction losses in pipe and head in the supporting components of the valve, knee, measuring instrument, reducer and T-branch. The calculation of heating load in the DECY 13 MeV cyclotron is based on the amount of electrical power that required in each sub-system. From the calculation it is known that for cooling the equipment so that all incoming and outgoing chiller temperature remain at 25 °C and 10 °C required a total cooling water discharge of 123 L/min. In the distribution it is used two pumps: pump 1, types of WL 40/4 with floe rate 50,6 L/min, head 103,43 m to serve the RF-dee, ion sources and vacuum system. (author)

[en] Installation and evaluation of grounding system for EBM industrial latex at PTAPB using multiple rod has been carried out. Installation is based on the needs of small grounding resistance (R_p) value by choosing the shape, size and number of electrode and the electrodes planting location. The well backfilled with clay in order to obtain low soil resistivity ρ on surrounding the electrode. Installation is done by planting the electrodes copper rod (Cu) diameter of 16 mm in 2 wells, each consists of 4 pieces @ 2 meters length and 8 pieces @ 1 meter length through 2 layers soil. From the electrodes with a predetermined configuration, obtained the average measured value of R_p is 3.99 Ω in wells I and 5.82 Ω in wells II or R_p_t = 2,36 Ω in parallel, whereas the average of measurements value of electrodes is R_p_t = 1.97 Ω. From trial and error by varying of ρ it is obtained that the resistance on the upper soil R_1 = 6.53 Ω and R_2 = 10.41 Ω for the bottom soil or in parallel obtained R_p_I = 4.01 Ω for wells I, while for wells II R_1 = 7.72 Ω and R_2 = 23.64 Ω that if in parallel ob tined R_p_2 = 5.81 Ω. When resistance on I and II wells being paralleled R_p_t value is 2.37 Ω. The difference values of measured and calculation R_p_t value is 0.40 Ω, it might be caused by the difficulty on R_p_t measurement and the effect of inhomogeneity of ground resistivity from one place to another place. From the evaluation found that the influence of length and depth of planting electrodes more dominant compared to the number of electrodes. With the difference of 0.55 m electrode depth and 2 times the number of electrode obtained a very large difference in resistance i.e 18.47 Ω. (author)

[en] The high frequency transformer (HFT) of one phase, 15 kW, 7/17.5 kV, 40 kHz made for latex EBM has been operated but its characteristics is still unknown. Efficiency is an important characteristic of the HFT to be analyzed in order to determine its ability to supply the power of high voltage source of EBM at various electron beam currents. The analysis was performed by calculating the core losses and winding losses where core loss depends on the material type while winding loss depends on its current and resistant. In this case the resistant value is determined by observing the temperature rise that occurs during operation. The core power loss W at the maximum magnetic induction B_m = 0.15T and the operating frequency of 40 kHz is 611.78 W while the total coil power loss for full load of 1.07 A is 9.85 W so that the transformer efficiency at this load is 96.02%. The efficiency of the transformer is calculated by varying the load current I_b_e (electron beam current) where the coil power loss is proportional to the square of the load current. Maximum efficiency of the HFT under full load is 95.71% which is occurred at I_b_e of 11 mA or at 92.4% of full load. At larger I_b_e ,eg. 12 mA, the HFT has been experiencing overload conditions by 9.34%. When compared with the power transformer which has maximum efficiency of about 80% of full load, therefore the home made HFT has greater maximum efficiency in percent of load. The HFT efficiency also has the same tendency as this type of power transformer, where the greater the load the greater efficiency is. (author)