784 – Design of Thermal Systems .

Assignment Execution Instructions Design of Thermal Systems (MECH 0009.1)

You are required to complete the full assignment accurately, professionally, and in a well-structured format. Follow the instructions below carefully to ensure all requirements are fully met.

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### General Requirements

– Answer all questions clearly and in your own words.

– Show all steps, equations, and assumptions used in calculations.

– Maintain a formal engineering writing style.

– Use proper units and consistent notation throughout.

– Prepare the report in Microsoft Word using:

– Font: Times New Roman, Size 12

– Headings: Size 14, Bold, Capitalized, Underlined

– Include:

– Title Page (with name, ID, module, instructor, and date)

– Table of Contents

– Proper Harvard-style references

– Page numbering

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### Q1(a): Cost Estimation Methods (300400 words)

– Explain and justify the most suitable cost estimation method for each stage:

1. Feasibility Study select appropriate method

2. Preliminary Design select appropriate method

3. Detailed Design select appropriate method

– Compare briefly between methods (Expert Opinion, Analogy, Parametric, Engineering).

– Justify each choice based on data availability, accuracy, and project stage.

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### Q1(b): Cooling Load Calculation (CLTD/CLF Method)

#### Step 1: External Cooling Load

– Calculate heat gain from:

– Wall use U A CLTD

– Roof use U A CLTD

– Window (conduction) use U A CLTD

– Window (solar) use SHGF Area SC CLF

– Show all calculations clearly with units.

#### Step 2: Internal Cooling Load

– Occupants:

– Sensible = number 75 W

– Latent = number 55 W

– Lighting:

– Total power CLF

– Equipment:

– Total power of computers

#### Step 3: Total Cooling Load

– Sum all external and internal loads.

– Convert total load from Watts to Tons of Refrigeration (TR):

– 1 TR = 3.517 kW

– Present final answer clearly.

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### Q2: Heat Exchanger Analysis

– Clearly state assumptions (steady state, no heat loss, etc.).

#### (a)

– Calculate:

– Heat capacity rate: C = Cp

– Identify Cmin and Cmax

– Compute capacity ratio: c = Cmin / Cmax

#### (b)

– Calculate NTU:

– NTU = (U A) / Cmin

#### (c)

– Use the effectiveness equation to compute .

#### (d)

– Calculate:

– Heat transfer rate: Q = Cmin (Th,in Tc,in)

– Outlet temperature of cold water

#### (e)

– Apply LMTD method:

– Calculate T1 and T2

– Compute LMTD

– Compare results with NTU method

– Provide a brief comparison and explanation.

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### Q3(a): Vapor Compression Cycle (Minimum 200 words)

– Explain the four main processes:

1. Compression

2. Condensation

3. Expansion

4. Evaporation

– Describe energy transfer and refrigerant behavior.

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### Q3(bf): Experimental Analysis

– Complete Table Q3a and Q3b using given or experimental data.

– Use psychrometric chart to determine:

– Humidity ratio

– Enthalpy

– Dew point

#### (c)

– Plot inlet and outlet states.

– Identify the process (cooling, dehumidification, etc.).

#### (d)

– Calculate Sensible Heat Ratio (SHR):

– SHR = Qsensible / Qtotal

– Interpret the result.

#### (e)

– Calculate actual COP:

– COP = Q / W

– Compare with Carnot COP.

– Provide at least 3 reasons for differences.

#### (f)

– Suggest at least 3 improvements for system efficiency:

– Based on experimental observations

– Clearly justified

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### Final Check Before Submission

– Ensure all calculations are correct.

– Ensure diagrams/plots are included where required.

– Ensure clarity, organization, and proper formatting.

– Attach all simulation or supporting files if applicable.

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### Important Note

The work must be original. Do not copy from external sources. Any similarity or plagiarism will result in penalties.

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Deliver the assignment as a complete, well-organized report ready for submission.