THERMAL BUILDING SIMULATION WITH MAPLESIM Adhi Susilo and Martin Bauer Faculty of Architecture and Civil Engineering Hochschule Augsburg, Germany

Outlines Abstract Introduction Modelica and MapleSim Basic model Room model and Heat gain Results Conclusions

Abstract This work is based on a systematic approach in construction process. MapleSim is one of simulation tools that is able to work on both approaches; causal and acausal. VDI 6020 is a benchmark to evaluate the model.

Introduction Formalizing Building Construction Process Design process Creating a system Systematic Engineering Design (7 steps in 4 phases) Planning and task clarification Conceptual design Embodiment design Detail design

Design process Analyzing Synthesizing

Systematic Engineering Design Ref. : Pahl / Beitz – VDI 2221

Phases of Contruction Requirements Function elements Construction Generalized construction devices Construction devices Single components

Function elements Lead water Roof Insulate thermal energy Wall o o o Lead water Insulate thermal energy Insulate th.energy Ventilate air System boundary

General construction devices Principle graph monopitch roof Insulate energy Lead water Lead water System boundary Ventilate air External Wall & Window

Insulate thermal energy Construction devices A wall (three layers) model o o o o o o o o o o o o o Roofing layer Ventilation layer Underlayment layer (Wood) sheathing l. Vapour Barriers layer Insulation layer Siding layer Ventilate air System boundary Lead water Insulate thermal energy (Roof) area

Modelica and MapleSim The equation based language, or called an acausal system. There are many basic components in its library, including electrical, mechanical, and thermal devices; sensors and sources; and signal blocks Example of thermal library components Boundary Condition Controls Fixed Temperature Heat Transfer Components Body Radiation Convection Heat Capacitor Thermal Conductor Prescribed Heat Flow

Basic Model We take VDI 6020 Example 1 as a bench mark External Wall & Window

Material properties of the Room type S (VDI Richtlinie 6020, 2001)

Building element A typical layer A window with air gap is simulated by radiation and convection component

Room Model and Heat Gain

Internal Gain (An example of the internal gain within ten days)

Results

Result from MapleSim 4

Conclusions Further Work The simulation model can be prepared like a systematic approach in construction process. A complex system is broken down into basic components. Then, rearranging and synthesizing the basic component to simulate the overall system. Though the gradient of the steady state of both results is different, but both simulations reach steady state at around day 60. Further Work Before bugs fixed, we have to create a smooth input with combination of other functions, for example a pulse function is substituted by combining sine function and on-off function. Extending this model to accommodate a multizone building.

Acknowledgement Thank you This work was supported by Urlaubskasse des Bayerischen Baugewerbe e.V. Thank you