Question 7.9: Modeling of a Pneumatic System with Simulink Consider the pn...
Modeling of a Pneumatic System with Simulink
Consider the pneumatic system in Example 7.2. Construct a Simulink block diagram to find the pressure inside the container, p(t), which is assumed to be 0 \mathrm{~Pa} initially. The pressure at the inlet is assumed to be 101.325 \mathrm{kPa}.
The dynamics equation obtained in Example 7.2 is
\frac{R V}{R_{\mathrm{air}} T} \frac{\mathrm{d} p}{\mathrm{~d} t}+p=p_{\mathrm{i}^{\prime}},
where R V /\left(R_{\mathrm{air}} T\right)=1.19 \times 10^{-2} \mathrm{~s}. Solving for the highest derivative of the output p gives
\dot{p}=84.03(101,325-p),
which can be represented by the block diagram shown in Figure 7.36. One Integrator block is used to form the container pressure p, which is fed back to form the variation rate \dot{p}. Note that the system input is the inlet pressure p_{\mathrm{i}}, which is constant and is represented using a constant block. Run the simulation. Double-click the Scope block and the resulting output of the pneumatic system p(t) is shown in Figure 7.37.
