流体动力学基本原理

This will be a busy week diving into valves and pumps. We will discuss how basic valves function, how to use them in hydraulic circuits, and how to calculate pressure drop for a given flow rate, or vice versa. The videos will directly address the discussion on the forum about seeing hydraulic components working in real world circuits. In our discussion of pumps we will look at many different positive displacement pumps, exploring flow ripple and pump efficiency, look at the supporting components that form a hydraulic power supply, and see how we can make a transmission with a hydraulic pump and a motor. We are now into the heart of this course; we hope you enjoy seeing the components come together into useful circuits.

This week is entirely devoted to you learning how to use Simscape Fluids (formerly SimHydraulics), the fluid power simulation application that we use in the course. The lecture provides an introduction to computer-based, object-oriented simulation, and goes through a demo of using Simscape Fluids. The homework assignment contains the real work because this is where you will learn to use Simscape Fluids. The homework ends with an open-ended problem that encourages you to branch out on your own and create and run simulations based on examples listed in the course Simscape Fluids resource page or on any other fluid power system that interests you. We will be monitoring the discussion boards to help you with any technical problems with Simscape Fluids. *NOTE: The lecture videos were created using an earlier version of SimHydraulics; some small difference exist with the most recent version of Simscape Fluids, but the general approach is the same. *THERE IS NO QUIZ THIS WEEK as we recognize that a few of you may not be able to get Simscape Fluids running on your computer. Happy simulating!

This week we will take a dive into hydraulic fluids (no pun intended) and how their properties and behavior influence the circuit operation. In the lectures, you will see the water hammer effect and explore the assumption of fluid incompressibility. We encourage you to use your new knowledge of fluid behavior and simulation to create virtual experiments that explore how fluid properties influence the behavior of a circuit. Share your observations on the discussion forum.

This week you will learn about two new components, the accumulator, which stores hydraulic energy, and the servo valve, which provides fast and precise flow control. We will then be pulling together topics from throughout the course to look at servo hydraulic systems and hydraulic hybrid vehicles. You will get a chance to use simulation to explore how these advanced systems function and how the behavior of individual components influences the system operation.