Results Of The Experiment Along With The Efficiency

Resultsthe Results Of The Experiment Along With The Efficiency And Un

The experiment was designed to measure fluid flow characteristics using various instruments, notably the rotameter and a virtual rotameter, alongside calculations of discharge coefficients, flow coefficients, and Reynolds numbers. The primary goal was to analyze the accuracy and efficiency of these measurement methods under different flow conditions and to evaluate the uncertainties associated with each approach.

The collected data, presented comprehensively in the appendix, included measurements of pressure, flow rate, and motor parameters such as speed and input power. The initial phase focused on calibrating the measurement systems, particularly the virtual rotameter, by adjusting its scale factor through trial and error. An initial scale factor of 7.059 resulted in a substantial error margin of approximately 86%, indicating significant discrepancies between the virtual instrument and the standard rotameter readings. Subsequent adjustments led to a calibrated scale factor of 6.45, which notably improved accuracy, reducing the percent error to below 1% across most measurements, except for the lower flow rates where an error of 12% persisted.

The experimental results revealed a clear correlation between the discharge coefficient and the Reynolds number, consistent with established fluid dynamics principles. As shown in Figure 1, the discharge coefficient exhibited variations with respect to Reynolds number, supporting the understanding that the flow regime influences measurement accuracy and flow behavior. This relationship was further elucidated through the plotted data and linear fitting, which underscored the importance of precise calibration, especially when employing virtual measurement devices.

Analysis of the rotameter and virtual rotameter measurements highlighted their respective performance levels. Initially, the virtual rotameter's scale factor required refinement to align with actual flow conditions. The calibration process involved gradually opening the inlet valve until noticeable changes in motor speed occurred, aiming to capture the lower flow rates accurately. The motor's no-load speed of around 1400 rpm was used as a reference point to approximate flow conditions. Recordings of motor speed, force, and power input recorded during the process enabled better characterization of the flow environment.

The data reflected that with the optimized scale factor, the virtual rotameter could reliably replicate the readings obtained from the standard rotameter, with percent errors reduced significantly. For higher flow rates, errors dropped below 1%, demonstrating the effectiveness of calibration. However, at lower flow rates, measurement uncertainties remained slightly elevated, emphasizing the challenges of accurately capturing low-volume flows.

An important aspect of the analysis involved evaluating the uncertainties in the measurements. Relative uncertainties were estimated at ±0.001 for pressure measurements and ±0.01 for mass flow rates, which influenced the overall calculation of discharge and flow coefficients. These uncertainties are critical for validating the accuracy of the experimental data and ensuring the reliability of conclusions drawn from the study.

Furthermore, the discharge coefficient's dependency on the Reynolds number was confirmed through multiple plots and linear fits. The relationship is pivotal in understanding flow regimes, especially in applications like pipeline design and flow measurement, where turbulent and laminar flows exhibit distinct behaviors. The experimental data aligned with theoretical expectations, with the discharge coefficient tending to stabilize at higher Reynolds numbers indicative of turbulent flow conditions.

In conclusion, the experiment demonstrated that with proper calibration, virtual measurement devices could effectively replicate traditional instruments, significantly reducing measurement errors. The detailed analysis of the discharge and flow coefficients provided insights into fluid flow dynamics and verified the applicability of these measurement techniques across a spectrum of flow conditions. Future work could focus on refining calibration procedures further and exploring automated methods for dynamic adjustment of scale factors to enhance accuracy in real-time applications.

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