ESP-r modules

ESP-r is composed of a number of programs, each contributing certain facilities to the simulation process. While they share a common interface style and access may of the same descriptive files and databases it is recommended that the user read the synopsis of each of the modules.

Simulation work with ESP-r tends to involve several modules being active at the same time. It is not unusual to have access to the problem image and attributes active at the same time as a simulation is running and a prior results database is being browsed. The optional external image is from a simulation session, the only consession made before capturing the image was that some applications that might have been iconised to reduce screen clutter where retained on the screen.

an "almost" typical simulation session


ESP-r Layout & Directories

ESP-r product model


ESP-r holds information on thermophysical and optical properties, plant system components, standard event profiles and wind pressure distributions in databases. Most of these are in a binary format for random access and data security although ASCII formats are supported for archiving and transmission purposes. In most cases access to the database contents are via the Project Manager and standard listing and editing facilities are provided.

Boundary conditions are held in climate data files, one for each year and location. At the current time there is data for a number of locations on many continents - contact ESRU for particulars.

Problem Composition

Simulation problems are held in a number of data structures which can be viewed in terms of a `product model'. Simulation tends to require a detailed representation of the form, fabric and systems within a given problem. Although initially daunting it is possible to view the product model as a hierarchy of information related to objects such as sites, buildings, rooms, surfaces and components.

If you want to find out about the process of creating a new problem press here.


ESP-r provides two paradigms for control, `ideal' controls for use in early design investigations and a more realistic implementation which can be associated with detailed representations of plant systems. The `ideal' systems have no inertia or time dependent characteristics. Detailed plant representations include inertia and time dependent characteristics at several levels of granularity and have more robust control facilities.

All control functions are defined by sensors which are located at for example an air node, surface, or node within a plant component; by actuators located at an air node, surface or plant component; and by a schedule of operation, setpoints and control laws. The specification of control systems within the Project Manager is via selection of lists of options and specification of values.

If you want to see a discussion of control press here.

Problem Types

ESP-r is a dynamic thermal simulation program which is able to address a range of questions related to the built environment. It is a finite volume method in which the `product model' is transformed into a matrix of state-space equations and the flows of energy in the problem enclosure, plant components and mass flow network are solved.

If you want to see a discussion of the types of problems which ESP-r works with press here.

If you want to find out about the process of creating a new problem press here.

Analysis Facilities

ESP-r provides a rich set of analysis facilities from which the user can extract almost "state-variables" such as the temperature at an air node, layer within a wall or a coil within a plant component or the flux at points within the problem and integrate and display them in several forms. The simulation environment is particularly strong in its support for energy balance reporting.

If you want to see a discussion of the analysis facilities press here.

Problem file contents

The product model of a simulation problem is held in a number of files within a UNIX workstation. There are several file types which, broadly speaking, contain information related to a particular portion of the product model. For example information on control systems is kept separately from that of the form and fabric of thermal zones. The topology of the problem is held separately from that of the schedule or occupancy and equipment usage. Indeed for each thermal zone there are three required files and depending on the level of descriptive detail, one or more special files.

In most cases you will not be required to either remember the names or location of files as they are by default derivatives of the problem name or the names given to each zone. Indeed, to browse most problems all you need to know is the name of the problem description file which holds the names of all the files, databases and notes related to the problem.

If you are a novice user you may not wish to proceed beyond this overview to the details of the problem description files.