ES GA1

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Group Activity 1: Off-design of a Heat Exchanger Mechanical Engineering - Energy Systems Authors: •Group xx: xxxxx xxxxx (xxxxxxxx), xxxxx xxxxx (xxxxxxxx) •Group xx: xxxxx xxxxx (xxxxxxxx), F abio Santoro (xxxxxxxx) Lecturer:Prof. Stef ano Consonni T eaching Assistants:Riccardo Cremona, Hamidreza Heydari and Nima Razmjoo Academic year:2025-2026 Contents 1 Introduction and Data 2 2 Design Analysis 4 3 Off-design – Scenario A 6 4 Off-design – Scenario B 11 5 Further considerations between all scenarios 15 GA Assessment 16 References 16 1 Energy Systems - Report GA1 - Groups xx and xx 1. Introduction and Data The scope of this activity is the design of a counter-flow shell & tube heat exchanger (HE) used to heat up a stream of water from environmental temperature to saturated vapor conditions (Figure 1). The heat source is hot geothermal brine (water with dissolved salts). Figure 1: Example scheme of a counter-flow shell & tube heat exchanger with one shell pass and one tube pass In the following table, we can find all data necessary to design the device. The brine is defined as hot side (H) and the water as cold side (C): Table 1: General data Name U.M. Hot Side (H) Cold Side (C) ˙mkg/s 25 5 pbar 50 3 Tin ◦C 260 25 cp kJ/(kg·K) 4.25 4.2 hin kJ/kg - 105.11* The water is heated until it reaches complete vapor saturation. Since it enters the heat exchanger at sub-cooled liquid conditions, the exchanger is divided into two sections: the first section, labeled P RE, where the water is heated to the saturated liquid state, and the second section, labeledEV A, where phase change occurs as the water evaporates from saturated liquid to saturated vapor. These two sections are characterized by different heat exchange coefficients with the respective values of UP RE = 1.5kW/(m 2K)…