CostCost EstimationEstimation OfOf AA HeatHeat ExchangerExchanger

Group Members

Chinthaka Perera

Chris Peng

Sandy Lee

Terry Peters540:343 Engineering Economics Spring 1998

Outline

• Introduction and Problem Definition

• Designs of Heat Exchangers

• Base Cost Estimation

• Complete Cost Estimation

• Conclusions & Recommendation

• Questions

540:343 Engineering Economics Spring 1998

Problem Definition

•Heat cold water from 15 oC to 85 oC using the minimum resources

•Area Limited to 50 square meters

•Minimize the cost of operation and maintenance of the machine

540:343 Engineering Economics Spring 1998

Efficiency: 48%

Power: 7.317x10 5 Watts

Length of Pass: 4.7 meters, Life Cycle 5 yr.540:343 Engineering Economics Spring 1998

Shell And Tube Heat Exchanger

Counter Flow Heat Exchanger

Efficiency: 48%

Power: 7.317 x 105 Watts

Length 129.55 meters, 8 revolutions, Life Cycle: 5yr.540:343 Engineering Economics Spring 1998

Cross Flow Heat Exchanger

Efficiency: 61%

Power:2.92 x 105 Watts

Area: 28.4 square meters, Tubes: 7898, Life Cycle 25 yr.540:343 Engineering Economics Spring 1998

Summary of Designs

Power(Watts)

LifeCycle

Efficiency

Shell &Tube

7.137 E5 5 yrs 48 %

CounterFlow

7.137 E5 5 yrs 48 %

CrossFlow

2.92 E5 25 yrs 61 %

540:343 Engineering Economics Spring 1998

Base Cost Estimating Technique

Base Cost = Cost of Materials to Construct Heat Exchanger

+ Cost Of Installation of Heat Exchanger

Conversion of Base Cost to Annual Worth using MARR = 10%

AWHeat Exchanger = (Base Cost) x (A/P,10%,Life Cycle)

540:343 Engineering Economics Spring 1998

Base Cost Estimation Of Heat Exchanger Designs

Using Annual Worth and assuming repeatabilityUsing Annual Worth and assuming repeatability

AWShell and Tube = - $ 14400

AWCounter flow = - $ 63400

AWCross flow = - $2200

Best Alternative for Heat Exchanger is

Cross Flow Heat ExchangerCross Flow Heat Exchanger540:343 Engineering Economics Spring 1998

Complete Cost Estimating Technique

Complete Cost = Base Cost + Operation and Maintenance

Conversion of Complete Cost to Annual Worth using MARR = 10%

AWHeat Exchanger = (Base Cost) x (A/P,10%,Life Cycle) +

(O & M) x (A/P,10%,Life Cycle)

540:343 Engineering Economics Spring 1998

Complete Cost Estimation

•Base Cost of Cross Flow Heat Exchanger - $ 2200

•Operation and Maintenance Cost + Cost of Gas - $ 2300

540:343 Engineering Economics Spring 1998

Total Cost Over Life Cycle - $ 4500

Conclusions & Recommendation

•Cross Flow Heat Exchanger is the most effective for the purpose

•Cross Flow Heat Exchanger is the most Cost EffectiveAside:

The Shell & Tube and Counter flow reused waste to heat water.

540:343 Engineering Economics Spring 1998

Recommendation : Cross Flow Heat Recommendation : Cross Flow Heat ExchangerExchanger

Questions ??

Design of Heat Exchanger…??

Base Cost Estimating Technique…??

Complete Cost Estimation…??

Choice of Heat exchanger …??

540:343 Engineering Economics Spring 1998