tailieunhanh - Die Casting Machine_2

Tham khảo tài liệu 'die casting machine_2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Simpo PDF Merge and Split Unregistered Version - http Section . A simple flow in a straight conduit A simple flow in a straight conduit Figure General simple conduit description A simple and most common component is a straight conduit as shown in Figure . The simplest conduit is a circular pipe which would be studied here first. The entrance problem and the unsteady aspects will be discussed later. The parameters that the die casting engineers interested are the liquid metal velocity the power to drive this velocity and the pressure difference occur for the required desired velocity. What determine these parameters The velocity is determined by the pressure difference applied on the pipe and the resistance to the flow. The relationship between the pressure difference the flow rate and the resistance to the flow is given by the experimental equation . This equation is used because it works2. The pressure difference determined by the geometrical parameters and the experimental data which expressed by 3 which can be obtained from Moody s diagram. Figure Moody s diagram Jl D 2 J D 2g v Note head is energy per unit weight of fluid . Force X Length Weight Length and it Actually there are more reasons but they are out of the scope of this book 3 At this stage we use different definition than one used in Chapter D. The difference is by a factor of 4. Eventially we will adapt one system for the book. What have your membership dues done for you today plagiarise copyright 2000 by Dr. Bar-Meir Simpo PDF Merge and Split Unregistered Version - http Chapter 4. Fundamentals of Pipe Flow has units of length. Thus the relationship between the Head loss and the pressure loss is A ĨĨ pg The resistance coefficient for circular conduit can be defined as Kf ỉị This equation is written for a constant density flow and a constant cross section. The flow rate is expressed as Q UA The cross sectional area of circular .