Power of nuclear reactors are measured through different methods. Neutron Detectors are usually used for online power monitoring of nuclear reactors. The measured power by neutronic detectors is affected by the positions of control rods (CRs) in the core. The main contribution of this research is to investigate the effect of the CRs position on power monitoring in Tehran Research Reactor (TRR) from experimental and simulation aspects. The MTR_PC package is used to evaluate the effect of partial insertion of the CRs on the power calibration at the operating core of the TRR. The maximum impact of CRs position on the NDs response is about 25% during a cycle. Results of the thermal power calibration experiment are used to investigate the CRs effect on power calibration. In the first experiment, the results of two thermal power calibrations, with the same monitoring power 2 MW at the different configurations of CRs, are compared. Experimental investigation illustrates 9.5% changes in the real thermal power of TRR, while simulation predicts about 11%. In the second experiment, the power of TRR is increased to 5 MW and the thermal power calibration has been repeated in the new position of CRs and its result is compared with 5 MW. Both of the experiment and modeling results predict a similar effect of CRs on power calibration.

核反应堆的功率通过不同的方法进行测量。中子探测器通常用于核反应堆的在线功率监控。中子探测器检测到的功率受堆芯中控制杆（CR）位置的影响。这项研究的主要贡献是从实验和仿真方面研究CR位置对德黑兰研究堆（TRR）功率监控的影响。MTR_PC软件包用于评估CR的部分插入对TRR的工作核心处的功率校准的影响。在一个周期中，CR位置对ND响应的最大影响约为25％。热功率校准实验的结果用于研究CR对功率校准的影响。在第一个实验中，两次热功率校准的结果是 比较了在不同CR配置下具有相同监视功率2 MW的情况。实验研究表明，TRR的实际热功率发生了9.5％的变化，而仿真预测约为11％。在第二个实验中，TRR的功率增加到5 MW，并且在CR的新位置重复了热功率校准，并将其结果与5 MW进行了比较。实验和建模结果都预测了CR对功率校准的类似影响。TRR的功率增加到5 MW，并且在CR的新位置重复了热功率校准，并将其结果与5 MW进行了比较。实验和建模结果均预测了CR对功率校准的相似影响。TRR的功率增加到5 MW，并且在CR的新位置重复了热功率校准，并将其结果与5 MW进行了比较。实验和建模结果都预测了CR对功率校准的类似影响。