Design projects for MER160

Or, engineering life as you will know it ...

PG Kosky, Jan 4, 2005

The design problems will cover:

• Engineering Design: • Thermosciences Review:• Engineering Ethics: • Piping Systems: Pumps and Fans:• Heat Exchangers:• Economic analysis: • Optimization:• Team Skills:

What’s expected of me

• I am the bad cop ... your customer

• I am an engineering manager, with a PE license– Many engineers have to pitch their ideas, proposals,

and respond to their customers– You should treat me as that customer as if your job

depends on it (in MER160 it’s 50% of your grade, in industry, it’s your job ... )

– Even crusty engineering managers like to hear physical justifications for approaches, formulae etc. – but don’t overdo it!

What’s expected of me

• Assume I really know my business but not about anything new you are presenting to me.

What’s expected of me

• In reality, most engineering managers are not Dilbertian fools!... but ...– I may use jargon, acronyms, and funny mixed units

– US companies often prefer/require engineering English units to SI (stupid them!) so expect to hear BTUs, ºF, hours, kW, lb, kg, as well as terms like COP, net positive suction head, velocity heads, and a host of others etc.

– In my experience, many engineering managers don’t even realize they are using shorthand so don’t be ashamed to ask for clarification when/where necessary

– The only stupid question is the one not asked

What’s expected of you

• You want me to adopt your method, design, product etc.– You will definitely need to justify it to me on solid

technical grounds– You will definitely have to justify it to me on solid

economic grounds (I may be betting my business (and your job) on your recommendations)

– You will give me persuasive professional presentations as well as well-written formal documentation.

Design project 1

• You will have a copy of it on line.– I want a design of a

novel water-source heat pump to use in northern climes where air-source units deliver too little heat as it gets colder.

W

Temperature

Supply water,15ºC

Returned water

Air to house, 40ºC10 kW

Recycled air, 20ºC

Condenser

Evaporator1

23

Expansionvalve

4

W

Temperature

Supply water,15ºC

Returned water

Air to house, 40ºC10 kW

Recycled air, 20ºC

Condenser

Evaporator1

23

Expansionvalve

4

Design project 1

• Do a thermo cycle analysis– You need to 1) Pick a refrigerant from the many in

CATT2– Try to get one with the necessary physical

properties as well as one that is environmentally friendly

– Look out for the engineering criteria as to pressures at the top and bottom of the cycle you need to deliver heat at 40ºC to house and not freeze the return water

Design project 1

• Heat exchangers mean that there are temperature drops to be accounted for both on the condenser side and the evaporator side.

• Remember LMTD means linear Q vs. T flows

Design project 1

41

2 phase Sat vap

Water, 15CT4 < Water <

Water HX

41

2 phase Sat vap

Water, 15CWater, 15CT4 < Water <

Water HX

Counter current HX

Air, in 20C

Air, out 40C

S/C vaporT2

Condensate, T3

Air, in 20C

Air, out 40C

S/C vaporT2

Condensate, T3

“Crossflow”

Design project 1

• Economics– Put together the capital, the cost of money

involved therein, the operating costs as a minimum.

– Given it’s a consumer item, you might want to add something for warranty work in the heat pump’s operating lifetime.

– Remember, in the end, the economics is there to help the intermediate customer, the heat pump installer, sell the heat pump to the final consumer.

Design project 1

• So, I expect – A good design– A good defense of your design– A solid group report with the details of your design

• So, you expect– I will be in class to answer questions after you

have started the project, Tuesday, Jan 11.– Me to be grumpy and live up to reputation