Page 1 of 4 ACS133 Physical Systems Assignment 2 Dr Anton Selivanov Assignment weighting 6% of overall module grade Assignment released Monday, 8 February, 00:00. Assignment due Thursday, 25 February, 12:00. Penalties for late submission Late submission penalties will be applied according to university policy https://www.sheffield.ac.uk/ssid/assessment/grades-results/submission-marking Feedback The aim is to provide feedback to students within two weeks from the submission deadline. Unfair means This is an individual assignment. Do not discuss your solutions/work with others. Submitted work must be wholly your own. Suspected unfair means will be investigated and may lead to penalties. See https://www.sheffield.ac.uk/ssid/unfair-means/index for guidance. Extenuating circumstances You must submit an extenuating circumstances form if you have any medical or special circumstances that may have affected your performance on the assignment. See https://www.sheffield.ac.uk/ssid/forms/circs for more information. Page 2 of 4 Assignment briefing and Marking criteria In doing the assignment, you should be prepared to use the MATLAB help system and do some of your own research to learn about functions or features you may need. Your answers will consist of your code to solve the assignment questions shown below. Your code will be re-run during marking to see if it solves the tasks. Task 1 is worth 10 marks. Tasks 2(a) and 2(b) are worth 10 marks each. The marks will be divided between (i) presentation and (ii) correctness, with greater emphasis on the latter: (i) Your code should be well designed and use a consistent style. It should have good indenting and use sensible variable names. It should have useful comments. Any output produced should be well presented. Scripts must be headed with comments that include the title, the purpose of the code, your name, the date the code was finished. Functions should include help on how to use the function. (ii) Your code must actually work. It should not produce errors. It should not be dependent on pre-existing values in workspace or search paths that may not be available to another user. It should answer the question and produce correct results, giving the right answers with attention to detail regarding units, labels, etc. where relevant. Help Some help is available via the assignment briefing, plus material on Blackboard and MATLAB’s inbuilt help. If you need clarifications on the assignment questions, please, email me. Submitting your work: Submit a single ZIP file (*.zip, *.7z, *.rar) containing all your MATLAB files. You must submit the zip to Blackboard. Important: Before submitting, test your zip to make sure your unzipped code works when unzipped to a clean empty folder. This is what will happen when it is marked. (If you encounter problems uploading to Blackboard you can email the zip to me at [email protected] If you do this, please, do so from your university account) Page 3 of 4 Assignment tasks Task 1 A contra-flow heat exchanger consisting of a tube inserted inside another tube can be used to extract heat from a hot fluid stream. In the exchanger shown opposite the cold fluid flows through an inner tube and gains heat from the surrounding hot fluid. It enters with a temperature 1 and leaves at a higher temperature, 2. The hot fluid losing heat falls from temperature 2 to 1. The heat transfer can be modelled via the following equation: = ( (2 − 2) − (1 − 1) ln ( 2 − 2 1 − 1 ) ) where is the overall heat transfer coefficient (Wm-2K-1), is the surface area of inner tube (m2) and is the heat transfer rate (W). 1, 2, 1, and 2 are the cold in, cold out, hot out, and hot in fluid temperatures (K). Suppose a process is producing some hot fluid that must be reduced from 355 to 325. Water at 293 is available for cooling. A heat exchanger with a surface area of 0.45 2 and heat transfer coefficient value of 1000 −2−1 is available. The desired heat transfer is 15000. Can we achieve that with the available device? To find out, write a script to plot vs 2, output a message to say whether the heat exchanger can be used for this task and if so, determine the cold stream exit temperature for a heat transfer rate of 15000. Page 4 of 4 Task 2 The output of a potentiometer is measured by a meter having a resistance , as shown in the figure opposite. is the resistance of the total length of the potentiometer and is the resistance for a general contact position . The systematic loading error due to the resistance of the measuring instrument is given by: Error E R R R R R R R R R i t i t i t m t i 2 2 ( ) ( ) (a) Create a separate MATLAB m-file function to compute the systematic error. Provide detailed help for your function (e.g., describe the input and output arguments, add a derivation of the error equation to explain the purpose of the function). Include inside your function some code to check the supplied arguments are valid. (b) Create a MATLAB script that uses your function. Write the script to produce plots of the loading error vs resistance (at potentiometer positions = 0 to = , i.e., as the resistance goes from 0 to ) for the cases: = 0.01 , = 0.1 , = , = 100 , and = 10 6 all with = 10 V and = 1Ω. Include in your comments in your script the usual case you’d expect when using a scope or voltmeter. Put your plots for the five cases as subplots in one figure arranged as a 5×1 column. Set the figure to occupy the left half of full screen when the script is run. In a second figure plot each case on one axes but make the y-axis logarithmic. Set the figure to occupy the right half of full screen when the script is run. Add a legend placed northeast outside the plot to identify the five cases. 欢迎咨询51作业君
