Skip to content

Arrangement Identifier

Run the Arrangement Identifier MicroSim Fullscreen

This sketch uses the FanPedia MicroSim kit. To run it in the p5.js editor, add the kit files from ../shared-libs/ (fanpedia-sim.css, fanpedia-core.js, fanpedia-p5.js, fan-codes.js and fan-drawings.js, or their published URLs under https://moroshek.github.io/FanTASTIC-textbook/sims/shared-libs/) to the editor's index.html before pasting the sketch.

About This MicroSim

An arrangement number is a short answer to three questions: how is the fan driven, where is the impeller relative to the bearings, and what carries the bearings and the motor? This MicroSim shows ten schematic side views of centrifugal fans, one for each of Arrangements 1, 2, 3, 3SI, 3DI, 4, 7, 8, 9 and 10, in shuffled order. For each drawing you first answer the three feature questions and commit them, and only then name the arrangement. Splitting the drawing into features before naming it is the skill the activity practices.

The parts in each drawing are left unlabeled until you check your arrangement answer, so you have to read the picture: look for belts and sheaves or a coupling, look for anything on the inlet side of the impeller, and look at what holds the bearings and the motor.

Each question allows one attempt per drawing. Mastery is 8 of 10 arrangements correct on the first attempt; the feature answers are scaffolding and are scored separately (out of 30). There is no Explore mode: after the round, Start over deals a new shuffled set.

The schematics are simplified teaching drawings, not manufacturer outline drawings. Twin City Fan's arrangement drawings are on FanPedia pp. 20–23. Arrangement 2 comes from the AMCA arrangement standard and is not shown in FanPedia.

How to Use

  1. Read the drawing. Answer Drive (Belt, Direct with coupling, or Direct on motor shaft), Impeller (Overhung or Center hung) and Bearings carried by (Pedestal, Fan housing, Independent pedestals outside inlet boxes, or Motor only).
  2. Press Check features. Each feature is marked ✓ correct or ✗ incorrect, with the correct answer shown (green solid or red dashed outline on the control). If all three features are right, the arrangements consistent with them are highlighted in bold with an outline (for example, Belt, Overhung and Pedestal highlight 1, 9 and 10). If any feature is wrong, nothing is highlighted.
  3. Choose an arrangement and press Check arrangement. The parts of the drawing are labeled and the reason for the answer appears, with an extra hint when your choice is a common confusion (for example, picking 4 for a coupled fan, or 1 for an Arrangement 9 or 10).
  4. Press Next drawing. After ten drawings, See results lists each drawing and shows separate scores for arrangements (out of 10) and features (out of 30), the first-attempt score and the mastery line. Start over starts a new shuffled round at any time.

Keyboard: Tab moves between controls; the arrow keys choose within a list or the arrangement options; Enter checks the features, checks the arrangement or goes to the next drawing. Feedback is announced to screen readers.

Data label: "Schematics are simplified. Twin City Fan arrangement drawings: FanPedia pp. 20–23. Arrangement 2 is from the AMCA standard and is not shown in FanPedia.", shown under the drawing with the keyboard hint.

Iframe Embed Code

You can add this MicroSim to any web page by adding this to your HTML:

<iframe src="https://moroshek.github.io/FanTASTIC-textbook/sims/ch11-arrangement-identifier/main.html"
        height="742px"
        width="100%"
        scrolling="no"></iframe>

Lesson Plan

Learning Objective

The learner will distinguish ten centrifugal fan arrangements (1, 2, 3, 3SI, 3DI, 4, 7, 8, 9 and 10) from schematic side-view drawings by identifying the drive type, the impeller position relative to the bearings, and what carries the bearings and the motor (Bloom: Analyze, verb: distinguish).

Audience

New application engineers, inside and outside sales staff, manufacturer's representatives and others who read fan drawings and quotes.

Duration

10–15 minutes for one round of ten drawings.

Prerequisites

Activities

  1. Warm-up (2 min): Recall the three questions that make an arrangement number: drive, impeller position, and what carries the bearings and motor.
  2. Round one (8 min): Complete a full round of ten drawings. Before pressing Check arrangement, say aloud which feature rules out the other highlighted arrangements.
  3. Debrief (5 min): Compare the misses on the results screen. Discuss the common confusions the hints target.

Common Misconceptions Addressed

  • Every direct drive fan is Arrangement 4: choosing 4 for a coupled fan (3SI, 3DI, 7 or 8) adds "There is a coupling and a separate fan shaft, so this is not Arrangement 4."
  • Any fan with a coupling is Arrangement 7, whatever the impeller position: choosing 7 for Arrangement 8 points out that the impeller is overhung.
  • Arrangements 1 and 9 differ in impeller position: they share the same three features, and the hint says they differ only in motor location (as does 10).
  • Arrangements 2 and 1 are the same: choosing 1 for Arrangement 2 points out that the bearings are on a bracket carried by the housing, not on a pedestal.

Assessment

  • First-attempt score shown as "Arrangements correct: n of 10"; mastery is 8 of 10 on the first attempt in one round.
  • "Features correct: n of 30" shows whether a miss came from misreading the drawing or from mapping correct features to the wrong number.
  • Discussion check: explain why drawings 1, 9 and 10 share the same three features but have different arrangement numbers.

References

  1. FanPedia: The Fan & Blower Encyclopedia - Twin City Fan; pp. 20–23 (centrifugal arrangement drawings and captions), p. 30 (impeller orientation), pp. 162–168 (arrangement technical descriptions).
  2. AMCA Standards - Air Movement and Control Association International, ANSI/AMCA Standard 99, Standards Handbook: drive arrangements for centrifugal fans (source of the Arrangement 2 definition used here).
  3. Chapter 11: Drives and Standard Fan Arrangements - the arrangement definitions and worked examples in this textbook.