A small problem related to computation
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I have a question: Gas is fed into a pipe, and it exits at the other end. I know that the allowable pressure is 0.55 MPa and the flow rate is 5 tons per hour. How can I calculate the cross-sectional area of the inlet?
Explanation: 1. First, it is necessary to determine the physical properties of the gas in its moving state, such as density, dynamic viscosity, Prandtl number, etc； 2. Obtain the values related to the pipeline: the relative roughness k of the inner wall of the pipe, the length of the straight sections, the number of elbows, valves, or tees, as well as the corresponding local resistance coefficients ； 3. Determine the thermodynamic conditions and compression state of the gas during flow; generally, if the pipe is very short, it can be considered an adiabatic flow ； If the gas flow velocity is less than 0.1 Mach number, it can be considered incompressible flow. In such a case, the calculation is relatively simple. 4. Calculation method: The iterative method can be used. That is, first assume a velocity, calculate the Reynolds number based on this velocity, determine the flow regime and resistance system according to the value of the Reynolds number, and then find the frictional loss along the flow path. This value is then compared with the given pressure drop; by repeating this process, good results can be obtained ； If mathematical software is used, equations can be written directly and solved using matrices.
First, the volumetric flow rate must be calculated, then the area of the pipe diameter is determined based on the flow velocity, and finally the pipe diameter is fixed.
5t/h is mass flow rate, not flow velocity