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Client Comments on Report

We received your report. Your observations about the difficult installation and potential failure of the thermocouple are interesting. What are your recommendations? Your finding that energy to produce the product dominates use is interesting. Does your calculation of 5.5 hours for freeze time match observation? Are there ways to reduce this time?

Detailed comments:

• Your description of production function is very clear. Does the fill really work on a timer? How does it compensate for different flow rates in the feed line? How are the circuits closed and opened? A picture or diagram would help.
• Any general findings from your BOM? Please include a picture or drawing of the assembly with parts of the BOM labeled. Where does the valve show up?
• In your DFE you mention that the motor runs for 15 minutes per cycle. Why does it run so long? Why do you not include the heating element? Also, how much additional energy must be provided by the refrigerator to continuously freeze new water entering the freezer?
• Your BOM lists the tray material as unknown, your DFMA reports that it is injection molded (thus with integrated plastic), and your analysis assumes aluminum. Which is it, and how do you know?
• Your DFA comments are pretty short. Were the DFA guidelines followed?
• Your analysis is very short, and there is not enough documentation for us to understand what you did. You mention simple analytical solutions - where are those? The shape shown in Figure 1 does not appear to match the tray shape. Is part of this shape water and part aluminum? Why does Figure 3 not show a flat spot at zero degrees during phase change?
• What are your FMEA findings and conclusions?

We look forward to seeing your market research and new ideas in the next report.

Client comments on the Mechanical Analysis

This well-performed mechanical analysis focuses on thermodynamics of ice maker, which is critical to its functionality. Here are few comments to the analysis:

• In your bill of material, the material of ice tray is listed as unknown metal, but this analysis seems to assume the material as aluminum without further explanation. Please check the consistency in your document.
• Please list the thermal properties of water and aluminum you used in the FEA.
• Currently we can not tell how the boundary conditions and initial conditions are applied in your FEA model. Please indicate them clearly in Figure 1 by using textboxes.
• It is worthy a note that converting 1 gram of ice at 0 °C into 1 gram of water at 0 °C requires additional 333 J of heat. Please make sure this is taken into account and added into your assumptions.
• Please give more conclusions upon your analysis results. For example, can the simulated 5.5 hours represent the practice freezing time? How do you apply the single-cube analysis results to the whole tray?