Practice with building mass balance models.—-one page with single
Part 2: Practice with building mass balance models. Hint – Chapter 4 of your textbook will be a good reference for this task. Devise a simple conceptual model that represents mass, energy, or material flow through any system of your choosing. Think boldly and broadly, then draw a picture of your conceptual model, making sure to include the elements listed below. Clearly define the elements in your model on your diagram. Then test it to see if it works! For example, if you are developing a conceptual model of the fate of socks in your house, can you track the fate of your socks through the entire house? If you purchase new socks and discard old, can you account for these actions in your model? a. The Compartment: This represents where and in what form the stock is stored in a system. For example, if you are interested in a model of your finances, you would define the compartment as your bank account. c. The system boundary: This represents the bounds on the system of interest. It clearly indicates what is outside the system and what is internal. The movement of mass, energy, materials, etc., is with respect to this boundary. b. The Stock: The stock (M) is simply the fundamental unit that is being tracked, balanced, and inventoried. It is an amount. For example, a conceptual model of your finances has as the stock dollars or M$ (if confined to the U.S.). If you are developing a conceptual model of the fate of socks in your house, then the stock is the quantity of socks or Msocks. c. Flows: The flows (F) represent the rate of input, output, transformations of stock in your compartment in units of stock/unit time. The flow of income ($/month) into your bank account represents an input, while spending the money represents a mechanism that money flows out of your bank account (in units of $/month). Transformations also represent flows out of your compartment, but in this case, the stock within the compartment changes form.